5th Iberian Meeting on Colloids and Interfaces, RICI5

Transcription

5th Iberian Meeting on Colloids and
Interfaces, RICI5
Book of Abstracts
EDITORS
Jacqueline Forcada
Josetxo Ramos
www.ehu.es
5th Iberian Meeting on Colloids and
Interfaces, RICI5
Book of Abstracts
26-28th June 2013
Donostia-San Sebastián
EDITORS
Jacqueline Forcada
Josetxo Ramos
PARTNERS AND SPONSORS
© Servicio Editorial de la Universidad del País Vasco / Euskal Herriko Unibertsitateko Argitalpen Zerbitzua /
University of the Basque Country Press
ISBN: 978-84-9860-832-8 / D.L.: BI-835-2013
www.ehu.es/argitalpenak
SCIENTIFIC COMMITTEE
Joan Estelrich
Jacqueline Forcada
Ramón González Rubio
Roque Hidalgo-Álvarez
Issa Katime
Luis Liz-Marzán
Eduardo Marques
Francisco J. Meseguer
Víctor Mosquera
Mª Luisa Moyá
Elisabete Oliveira
Artur Valente
Mercedes Velázquez Salicio
University of Barcelona
University of the Basque Country UPV/EHU
Complutense University of Madrid
University of Granada
CIC Biomagune
University of Porto
Associated Unit ICMM-CSIC/UPV
University of Santiago de Compostela
University of Sevilla
University of Minho
University of Coimbra
University of Salamanca
ORGANIZING COMMITTEE
Jacqueline Forcada (Chairwoman)
Josetxo Ramos (Secretary)
Isabel Goñi
Mariló Gurruchaga
Garbiñe Aguirre
Aintzane Pikabea
Ainara Imaz
Óscar Ameneiro
Navarre Government
University of Vigo
WELCOME to the RICI5 in DONOSTIA-SAN SEBASTIÁN
We are pleased to welcome you to the 5th Iberian Meeting on Colloids and Interfaces,
RICI5. This time the RICI5 is held in the beautiful city of Donostia-San Sebastián in the
Basque Country, from 26 to 28 June 2013.
As we will see over the course of the two and a half days of meeting, the diversity and
high scientific quality of the contributions of both senior and young Iberian and international
researchers will be a testimony of the vivacity of the field of Colloid and Interface Science
from synthesis to applications through characterization, modeling, and simulation.
The RICI5 will showcase the latest research and advances in this multidisciplinary field
continuing a series of successful Iberian meetings in Salamanca, Coimbra, Granada, and Porto
and pursues the objective of also succeed despite the uncertain times we are experiencing in
Iberia.
In addition to the oral program, different poster sessions will be run outside the lecture
room. Two special posters sessions will take place on Thursday 27 and Friday 28 (each
consisting of 1 hour) allowing for showing in 5 minutes 24 posters selected from the
presented. In all the contributions the participation of young researchers has priority. This
program will give us the opportunity to see the wide range of topics relating to this meeting
and to exchange ideas and discuss perspectives in the field. At the same time, you can take a
minute to visit the commercial exhibits to see the latest in analytical techniques related to
colloids and surfaces.
3 awards for the best oral presentations among young scientists and 2 awards for the best
poster presentations will be funded by the ACS journal Langmuir.
2 poster prizes will be given by the Wiley journal Particle. Consisting of a book voucher
to the value of 150 € and a 1-year subscription to the journal.
And last but not least, we hope that you will enjoy the social program including the
welcome cocktail on Wednesday 26 evening at the Miramar Palace and the conference
banquet on Friday 28 evening at the Real Club de Tenis Ondarreta.
Once again, ONGI ETORRIAK to Donostia-San Sebastián! We wish you a successful
and enjoyable meeting.
Jacqueline Forcada
Luis M. Liz-Marzán
Eduardo F. Marques
Chairwoman
Grupo Especializado de
Coloides e Interfases de las
Reales Sociedades Españolas de
Química y de Física
Grupo de Colóides, Polímeros e
Interfaces da Sociedade
Portuguesa de Química
PROGRAMME
Wednesday, 26th June 2013
10:00
13:00
13:45
13:50
13:50
14:35
14:35
14:55
Session
14:55
15:10
15:10
15:25
15:25
15:40
15:40
15:55
15:55
16:10
16:10
16:25
16:30
17:00
17:00
17:20
Session
17:20
17:35
17:35
17:50
17:50
18:05
18:05
18:20
18:20
18:35
18:35
18:50
REGISTRATION
OPENING CEREMONY
PL1
I1
Teresa López-León
ESPCI-ParisTech
Ralf P. Richter
CIC biomaGUNE
Chair:
R. Hidalgo-Álvarez
Biomolecular hydrogels – nature's playground for
supramolecular chemistry and physics
Liquid crystalline superatoms
3. SOFT COLLOIDS. SOFT NANOTECHNOLOGY. BIOINSPIRED SYSTEMS
O3.1
O3.2
O3.3
O3.4
O3.5
O3.6
A. C. N. Oliveira
Univ. Minho
J. Morros
IQAC-CSIC
M. Homs
IQAC-CSIC
R. G. Rubio
Complutense Univ. Madrid
S. G. Silva
Univ. Porto
A. Fernández-Barbero
Univ. Almería
Monoolein-based liposomes for siRNA delivery
The cooperative interaction between hydrophobically modified
inulin and DDAB
Polymeric nano-emulsions obtained by low-energy methods and
their use for nanoparticle templating
Stable capsules formed by liposomes coated by the layer-bylayer method
Serine-based catanionic liposomes as potential nanocarriers for
molecular delivery
Soft Particles for Tunable Nanophotonics
Coffee Break + POSTERS SESSION 1
I2
L. R. Rodrigues
Univ. Minho
Biosurfactants: Powerful Tools in
Microbial Enhanced Oil Recovery
Chair:
J. Estelrich
2. POLYMERS, POLYELECTROLYTES, SURFACTANTS AND GELS
O2.1
O2.2
O2.3
O2.4
O2.5
O2.6
R. Lund
Univ. Oslo
J. Sabín
Univ. Santiago Compostela
J. Miras
IQAC-CSIC
B. Stewart
Univ. Coimbra
A. Mezei
IQAC-CSIC
P. Rodríguez-Dafonte
18:50
19:05
O2.7
19:30
21:00
WELCOME COCKTAIL
M. L. Moyá
Univ. Seville
Non-equilibrium Kinetics in Block Copolymer Micelles
Observed by millisecond Time-Resolved SAXS and SANS
A unique colloidal “crystal-gel” structure observed in
microgravity conditions
pH-response and crosslinking time effect on chitosan nanofilms
Molecular Dynamic Simulations of Conjugated Polyelectrolytes
with Surfactants in Solvent Environments
Nanostructure of cationic surfactant-DNA complexes
Micellar Shape Transition in an Imidazolium based-surfactant
Binding of cationic single-chain/dimeric surfactants to bovine serum
albumin. Influence of the number of hydrophobic chains and the
presence of aromatic rings on the protein-surfactant interactions
Thursday, 27th June 2013
Univ. Pierre et Marie Curie
Molecular engineering of Inorganic and
Hybrid Nanostructured Materials
Chair:
L.M. Liz-Marzán
Rita S. Dias
NTNU, Trondheim
Effect of charge mobility and chain length on
the adsorption of poly-acids on oppositely charged nanoparticles. A Monte Carlo Simulation
Chair:
E.F. Marques
08:45
09:30
PL2
09:30
09:50
I3
Session
6. MODELING AND SIMULATIONS
09:50
10:05
10:05
10:20
10:20
10:35
10:35
10:50
10:50
11:20
11:20
11:40
11:40
11:55
11:55
12:10
Session
12:10
12:25
12:25
12:40
12:40
12:55
12:55
13:10
13:10
14:00
O6.1
O6.2
O6.3
O6.4
Clément Sanchez
A. Patti
IQAC-CSIC
M. Quesada-Pérez
Univ. Jaén
A. Moncho-Jordá
Univ. Granada
S. C. C. Nunes
Univ. Coimbra
Stochastic diffusion of isotropic and liquid crystal phases of rodlike
colloidal particles: Monte Carlo and Brownian Dynamics meet
Coarse-grained Monte Carlo simulations of thermo-responsive
polyelectrolyte nanogels
Effective electrostatic interactions arising in core-shell charged
microgel suspensions with added
Non-random adsorption of polyelectrolytes in regularly charged
surfaces. From single chain to multichain deposition
I4
O6.5
O6.6
Antonio M. Puertas
Univ. Almería
J. Faraudo
ICMAB-CSIC
A. Cuetos
Univ. Pablo de Olavide
The fluctuation theorem in dense colloids: A simulation study
A molecular insight on new vesicular systems formed by selfassembly of sterols and quaternary ammonium surfactants
Internal and free energy in a pair of like-charged colloids. Confined
and bulk fluids
7. BIOTECHNOLOGICAL APPLICATIONS
O7.1
O7.2
O7.3
O7.4
Lunch
R. Ahijado-Guzmán
Univ. Mainz
J. P. N. Silva
Univ. Minho
G. Luque-Caballero
Univ. Granada
A. M. Cardoso
Univ. Coimbra
Multiplexed Plasmon Sensor for Rapid
Label-free Analyte Detection
Chair:
M.E.C.D.R. Oliveira
Development of DODAB:MO Liposomes for Gene Delivery
Using AFM to study the complexation of DNA and anionic lipid
mediated by Ca2+ at the air-water interface
Gene Transfer Mediated by Bis-Quaternary Gemini Surfactants
Depends on Complex Architecture
14:05
14:25
I5
Session
5. SURFACES AND INTERFACES
14:25
14:40
14:40
14:55
14:55
15:10
15:10
15:25
15:25
15:40
15:40
15:55
15.55
16:10
16:10
16:25
16:30
17:00
O5.1
O5.2
O5.3
O5.4
O5.5
O5.6
O5.7
O5.8
Delfi Bastos-González
Univ. Granada
R. Fernandes
Univ. Porto
J. Maldonado-Valderrama
Univ. Granada
J. Benavente
Univ. Málaga
F. Ortega
C. L. Moraila-Martínez
Univ. Granada
C. Drummond
Centre Recherche Paul Pascal
T. Alejo
Univ. Salamanca
F. Martínez-Pedrero
I6
Session
4. COLLOIDS AND ENERGY
18:10
19:05
19:30
20:30
Chair:
M.M. Velázquez
NMR self-diffusion studies on the binding and exchange
dynamics between block copolymers and carbon nanotubes
Probing in-vitro digestion of interfacial protein structures in a
single droplet
Effect of porosity and surface material in the transport of ions
across nanoporous alumina membranes
Bulk and interfacial Microrheology
Segregation of silica particles with different size using driven
receding contact lines
Ions-Induced Nanostructuration of Hydrophobic Polymer
Surfaces
Quantum Dots onto Polymer and Surfactant self-assembled
Films: A Quartz Crystal Microbalance Study
Sudden Field Induced Sublimation In 2D Colloidal Crystallites
17:00
17:20
17:20
17:35
17:35
17:50
17:50
18:10
The Ion Specificity on Colloidal Systems
Juan A. Anta
Univ. Pablo de Olavide
Chair:
F.J. Meseguer
A rheological study of magnetic fluids based on highly
viscoelastic solvents
Band gap engineering with subnanometric metal (0) clusters:
O4.2
catalytic, electrocatalytic & photocatalytic applications
Nanostructured surfaces of conducting polymers and
I7
Inst. Telecomunicações, Lisbon
applications in organic photovoltaic cells
Chair:
POSTERS SPECIAL SESSION 1
M.L. Moyá
M. A. Fernandez-Rodriguez
M. A. Busquets
M. C. Neves
PSS01
PSS02
PSS03
Univ. Granada
Univ. Barcelona
Univ. Aveiro
M. Sánchez-Domínguez
D.
Rodríguez-Fernández
L. Polavarapu
PSS04
PSS05
PSS06
CIMAV, Mexico
CICbiomaGUNE
CICbiomaGUNE
S. Vílchez-Maldonado
T. Costa
C. M. G. Duarte
PSS07
PSS08
PSS09
IQAC-CSIC
Univ. Coimbra
Univ. Coimbra
A. F. Jorge
M. Fanun
PSS10
PSS11
Univ. Coimbra
CSRC, Palestine
O4.1
J. P. Segovia-Gutiérrez
Univ. Granada
M. A. López-Quintela
Ana Charas
Electron dynamics in nanostructured
metal-oxide films: novel routes towards
clean energy technologies
ASAMBLEA GECI
Friday, 28th June 2013
08:45
09:30
09:30
09:50
Session
09:50
10:05
10:05
10:20
10:20
10:35
10:35
10:50
10:50
11:20
11:20
11:40
11:40
11:55
11:55
12:10
12:10
12:25
12:25
12:40
12:40
12:55
12:55
13:10
13:10
14:00
PL3
I8
Tito Trindade
Univ. Aveiro
Hans Heuts
Eindhoven Univ. Technology
Inorganic nanocrystals as functional
building units for composites
Functional Hairy Particles and Films via Block
Copolymer-Stabilized Emulsion Polymerization
Chair:
E.F. Marques
Chair:
A. Elaissari
1. NANOPARTICLES: ORGANIC, INORGANIC AND HYBRIDS
O1.1
O1.2
O1.3
O1.4
S. Carregal-Romero
Univ. Marburg
R. Fenollosa
Univ. Politécnica Valencia
S. Fateixa
Univ. Aveiro
N. Pazos-Pérez
Univ. Bayreuth
Light-Addressable and Degradable Silica Capsules for Cytosolic
Release
Silicon Colloids with a strong magnetic response below 1.5
micrometers region
Resizing of colloidal gold nanorods using aqueous K2S2O8 and
morphological probing by SERS
Organized plasmonic clusters with high coordination number
and extraordinary SERS enhancement
I9
O1.5
O1.6
O1.7
O1.8
O1.9
O1.10
Lunch
Pablo Taboada
A. L. Daniel-Da-Silva
Univ. Aveiro
B. Nyström
Univ. Oslo
D. Jiménez de Aberasturi
Univ. Basque Country
L. Sacarabelli
CIC biomaGUNE
B. Martín-García
Univ. Salamanca
C. Rey-Castro
Univ. Lleida
Chair:
Nanosized particles: Beyond a simple tool
A.J.M. Valente
to fight against disease
Efficient eco-friendly dye nano-adsorbents based on biopolymer
surface functionalized magnetic nanoparticles
Microfluidic Self-Assembly of Polymeric Nanoparticles in
Aqueous Solutions and Controlled Drug Delivery
New applications modifying colloidal particles with ion-specific
ligands
Optimized Synthesis of Gold Nanorods
Shearing as a driven Force to direct the Assembly of
Nanocomposites Films
Dissolution of ZnO nanoparticles in aqueous media: A first
essential step in nanotoxicological studies
14:05
14:20
14:20
14:35
14:35
14:50
14:50
15:05
15:05
15:20
15:20
16:25
16:30
17:00
17:00
17:20
Session
17:20
17:35
17:35
17:50
17:50
18:05
18:05
18:20
18:20
18:35
18:35
18:50
18:50
19:05
Chair:
pH Responsive Nanoparticles for
Intracellular Release of Doxorubicin
V. Mosquera
Solid trivalent metal dodecyl sulfates: from aqueous solution to
O1.12
lamellar
Protein-nanoparticle bionconjugates: Enhanced protein stability
O1.13
and inhibition of fibrillogenesis
Enzymatic Modulation in the Growth of Gold Nanorods:
O1.14
Ultrasensitive detection of acetylcholinesterase inhibitors
Nanoparticles and nanodroplets as templates for inorganic
O1.15
synthesis: Crystallization at surfaces and interfaces
Chair:
POSTERS SPECIAL SESSION 2
R.G. Rubio
J. C. Mejuto
L. Pérez
G.
Prieto
PSS12
PSS13
PSS14
Univ. Vigo
IQAC-CSIC
I. S. Oliveira
D. Noguera-Marín
S. M. Novikov
PSS15
PSS16
PSS17
Univ. Porto
Univ. Granada
CICbiomaGUNE
M. Pujol
J. Juárez
J. A. Ruiz-López
PSS18
PSS19
PSS20
Univ. Barcelona
Univ. Sonora
Univ. Granada
J. M. Peula-García
O. Gonçalves
A.
L.
Barrán-Berdón
PSS21
PSS22
PSS23
Complutese Univ. Madrid
Univ. Málaga
Univ. Minho
I. Miraballes-Martínez
PSS24
Univ. de la República
O1.11
S- Bagherifam
Univ. Oslo
R. F. P. Pereira
Univ. Coimbra
S. Barbosa
M. Coronado-Puchau
CICbiomaGUNE
R. Muñoz-Espí
Max Planck Institute
I10
Romain Quindant
ICFO-ICREA
Towards an integrated plasmonic
platform for early cancer detection
Chair:
L.M. Liz-Marzán
CLOSING TALKS
CT1
CT2
CT3
CT4
CT5
CT6
CT7
A. Elaissari
Univ. Lyon
M. Grzelczak
CICbiomaGUNE
J. J. Cerdà
IFISC-CSIC-UIB
I. Pagonabarraga
Univ. Barcelona
T. Hellweg
Univ. Bielefeld
A. Guerrero-Martínez
B. Escribano
BCAM
19:05
19:15
CLOSING CEREMONY
20:00
CONFERENCE DINNER
Synthesis of Nano-coral like colloidal particles via water-in-oil
miniemulsion
Hydrophobic Interactions Modulate Self-assembly of Gold
Nanoparticles
Phase diagram of Magnetic filaments in bulk and near surfaces
Wetting-induced fluid entrainment and drop emission for driven
fluid filaments
Non-NIPAM based microgels: Tuning the volume phase
transition by copolymerisation and by particle architecture
Plasmonic Nanoparticles based on Colloid Chemistry
A chemical garden model for the formation mechanism of
brinicles
CONTENTS
CONTENTS
17
PLENARY LECTURES
PL1
LIQUID CRYSTALLINE SUPERATOMS
T. López-León, C. Blanc, M. Nobili, A. Fernandez-Nieves
41
PL2
MOLECULAR ENGINEERING OF INORGANIC AND HYBRID
NANOSTRUCTURED MATERIALS
C. Sanchez
42
PL3
INORGANIC NANOCRYSTALS AS FUNCTIONAL BUILDING UNITS
FOR COMPOSITES
T. Trindade
43
CONTENTS
18
INVITED LECTURES
I1
BIOMOLECULAR HYDROGELS – NATURE’S PLAYGROUND FOR
SUPRAMOLECULAR CHEMISTRY AND PHYSICS
R. P. Richter
47
I2
BIOSURFACTANTS: POWERFUL TOOLS IN MICROBIAL
ENHANCED OIL RECOVERY
L. R. Rodrigues, E. J. Gudiña, J. A. Teixeira
48
I3
EFFECT OF CHARGE MOBILITY AND CHAIN LENGTH ON THE
ADSORTION OF POLY-ACIDS ON OPPOSITELY CHARGED
NANOPARTICLES: A MONTE CARLO SIMULATION
R. S. Dias
49
I4
THE FLUCTUATION THEOREM IN DENSE COLLOIDS: A
SIMULATION STUDY
A. M. Puertas
50
I5
THE ION SPECIFICITY ON COLLOIDAL SYSTEMS
D. Bastos-González, L. Pérez-Fuentes, C. Drummond, J. Faraudo
51
I6
ELECTRON DYNAMICS IN NANOSTRUCTURED METAL-OXIDE
FILMS: NOVEL ROUTES TOWARDS CLEAN ENERGY
TECHNOLOGIES
J. A. Anta
52
I7
NANOSTRUCTURED SURFACES OF CONDUCTING POLYMERS
AND APPLICATIONS IN ORGANIC PHOTOVOLTAIC CELLS
A. Charas
53
I8
FUNCTIONAL HAIRY PARTICLES AND FILMS VIA BLOCK
COPOLYMER-STABILIZED EMULSION POLYMERIZATION
H. Heuts, M. Fijten, A. Muñoz-Bonilla, A. van Herk
54
I9
NANOSIZED PARTICLES: BEYOND A SIMPLE TOOL TO FIGHT
AGAINST DISEASE
P. Taboada
55
I10
TOWARDS AN INTEGRATED PLASMONIC PLATFORM FOR
EARLY CANCER DETECTION
R. Quidant
56
CONTENTS
19
CLOSING TALKS
CT1
SYNTHESIS OF NANO-CORAL LIKE COLLOIDAL PARTICLES VIA
WATER-IN-OIL MINIEMULSION
R. Ladj, Y. Mounier, R. Le-Dantec, H. Fessi, A. Elaissari
59
CT2
HYDROPHOBIC INTERACTIONS MODULATE SELF-ASSEMBLY OF
GOLD NANOPARTICLES
M. Grzelczak, A. Sánchez-Iglesias, T. Altantzi, B. Goris, J. Perez-Juste, S. Bals,
G. Van Tendeloo, S. H. Donaldson Jr., B. F. Chmelka, J. N. Israelachvili, L. M.
Liz-Marzán
60
CT3
PHASE DIAGRAM OF MAGNETIC FILAMENTS IN BULK AND NEAR
SURFACES
J. J. Cerdà, P. A. Sánchez, C. Holm, T. Sintes
61
CT4
WETTING-INDUCED FLUID ENTRAINMENT AND DROP EMISSION
FOR DRIVEN FLUID FILAMENTS
I. Pagonabarraga
62
CT5
NON-NIPAM BASED MICROGELS: TUNING THE VOLUME PHASE
TRANSITION BY COPOLYMERISATION AND BY PARTICLE
ARCHITECTURE
T. Hellweg, M. Zeiser, B. Wedel
63
CT6
PLASMONIC NANOPARTICLES BASED ON COLLOID CHEMISTRY
A. Guerrero-Martínez, L. M. Liz-Marzán
64
CT7
A CHEMICAL GARDEN MODEL FOR THE FORMATION
MECHANISM OF BRINICLES
B. Escribano
65
CONTENTS
20
ORAL COMMUNICATIONS
1. Nanoparticles: Organic, Inorganic and Hybrids
O1.1
LIGHT-ADDRESSABLE AND DEGRADABLE SILICA CAPSULES
FOR CYTOSOLIC RELEASE
S. Carregal-Romero, A. Ott, W. J. Parak
69
O1.2
SILICON COLLOIDS WITH A STRONG MAGNETIC RESPONSE
BELOW 1.5 MICROMETERS REGION
L. Shi, R. Fenollosa, F. Meseguer
70
O1.3
RESIZING OF COLLOIDAL GOLD NANORODS USING AQUEOUS
K2S2O8 AND MORPHOLOGICAL PROBING BY SERS
S. Fateixa, T. Trindade
71
O1.4
ORGANIZED PLASMONIC CLUSTERS WITH HIGH
COORDINATION NUMBER AND EXTRAORDINARY SERS
ENHANCEMENT
N. Pazos-Perez, C. S. Wagner, L. M. Liz- Marzan, F. J. Garcia de Abajo, A.
Wittemann, R. Alvarez-Puebla, A. Fey
72
O1.5
EFFICIENT ECO-FRIENDLY DYE NANO-ADSORBENTS BASED ON
BIOPOLYMER SURFACE FUNCTIONALIZED MAGNETIC
NANOPARTICLES
A. L. Daniel-da-Silva, A. M. Salgueiro, B. Creaney, T. Trindade
73
O1.6
MICROFLUIDIC SELF-ASSEMBLY OF POLYMERIC
NANOPARTICLES IN AQUEOUS SOLUTIONS AND CONTROLLED
DRUG DELIVERY
E. Dashtimoghadam, H. Mirzadeh, F. A. Taromi, B. Nyström
74
O1.7
NEW APPLICATIONS MODIFYING COLLOIDAL PARTICLES
WITH ION-SPECIFIC LIGANDS
D. Jimenez de Aberasturi, D. Hühn, R. Pinedo, I. Ruiz de Larramendi, T. Rojo,
J. M. Montenegro-Martos, S. Carregal-Romero, W. J. Parak
75
O1.8
OPTIMIZED SYNTHESIS OF GOLD NANORODS
L. Scarabelli, M. Grzeclzak, L. M. Liz-Marzán
76
O1.9
SHEARING AS A DRIVEN FORCE TO DIRECT THE ASSEMBLY OF
NANOCOMPOSITES FILMS
B. Martín-García, M. M. Velázquez
77
O1.10
DISSOLUTION OF ZNO NANOPARTICLES IN AQUEOUS MEDIA: A
FIRST ESSENTIAL STEP IN NANOTOXICOLOGICAL STUDIES
C. Rey-Castro, C. David, S. Cruz-González, J. Salvador, F. Mas, J. Puy, J.
Galceran
78
CONTENTS
21
O1.11
pH RESPONSIVE NANOPARTICLES FOR INTRACELLULAR
RELEASE OF DOXORUBICIN
S. Bagherifam, V. Hasirci, B. Nyström, G. W. Griffiths, G. M. Mælandsmo, N.
Hasirci
79
O1.12
SOLID TRIVALENT METAL DODECYL SULFATES: FROM
AQUEOUS SOLUTION TO LAMELLAR SUPERSTRUCTURES
R. F. P. Pereira, A. J. M. Valente, R. A. E. Castro, H. D. Burrows, V. de Zea
Bermudez
80
O1.13
PROTEIN-NANOPARTICLE BIONCONJUGATES: ENHANCED
PROTEIN STABILITY AND INHIBITION OF FIBRILLOGENESIS
S. Goy, A. Topete, A. Cambón, E. Villar-Alvarez, N. González, M. AlatorreMeda, E. Casals, V. F. Puntes, S. Barbosa, P. Taboada, V. Mosquera
81
O1.14
ENZYMATIC MODULATION IN THE GROWTH OF GOLD
NANORODS: ULTRASENSITIVE DETECTION OF
ACETYLCHOLINESTERASE INHIBITORS
M. Coronado-Puchau, L. Saa, M. Grzelczak, V. Pavlov, L. M. Liz-Marzán
82
O1.15
NANOPARTICLES AND NANODROPLETS AS TEMPLATES FOR
INORGANIC SYNTHESIS: CRYSTALLIZATION AT SURFACES
AND INTERFACES
R. Muñoz-Espí, V. Fischer, H. S. Varol, K. Landfester
83
CONTENTS
22
ORAL COMMUNICATIONS
2. Polymers, Polyelectrolytes, Surfactants and Gels
O2.1
NON-EQUILIBRIUM KINETICS IN BLOCK COPOLYMER
MICELLES OBSERVED BY MILLISECOND TIME-RESOLVED SAXS
AND SANS.
R. Lund
84
O2.2
A UNIQUE COLLOIDAL “CRYSTAL-GEL” STRUCTURE OBSERVED
IN MICROGRAVITY CONDITIONS.
J. Sabín, A. E. Bailey, G. Espinosa, B. J. Frisken
85
O2.3
pH-RESPONSE AND CROSSLINKING TIME EFFECT ON CHITOSAN
NANOFILMS
J. Miras, C. Liu, E. Blomberg, E. Thormann, E. Tyrode, S. Vílchez, J. Esquena,
K. Persson, P. Claesson
86
O2.4
MOLECULAR DYNAMIC SIMULATIONS OF CONJUGATED
POLYELECTROLYTES WITH SURFACTANTS IN SOLVENT
ENVIRONMENTS
B. Stewart, J. Pragana, S. M. Fonseca, T. Costa, A. T. Marques, U. Scherf, H.
D. Burrows
87
O2.5
NANOSTRUCTURE OF CATIONIC SURFACTANT-DNA
COMPLEXES
A. Mezei, R. Pons, M. C. Morán
88
O2.6
MICELLAR SHAPE TRANSITION IN AN IMIDAZOLIUM BASEDSURFACTANT.
P. Rodríguez-Dafonte, M. Figueira-González, V. Francisco, L. García-Río, E.
F. Marques, M. Parajó
89
O2.7
BINDING OF CATIONIC SINGLE-CHAIN/DIMERIC SURFACTANTS
TO BOVINE SERUM ALBUMIN. INFLUENCE OF THE NUMBER OF
HYDROPHOBIC CHAINS AND THE PRESENCE OF AROMATIC
RINGS ON PROTEIN-SURFACTANT INTERACTIONS
M. L. Moyá, V. I. Martín, A. Maestre, A. Rodríguez
90
CONTENTS
23
ORAL COMMUNICATIONS
3. Soft Colloids. Soft Nanotechnology. Bioinspired Systems
O3.1
MONOOLEIN-BASED LIPOSOMES FOR SIRNA DELIVERY
A. C. N. Oliveira, T. Martens, K. Raemdonck, A. C. Gomes, K. Braeckmans,
M. E. C. D. R. Oliveira
91
O3.2
THE COOPERATIVE INTERACTION BETWEEN
HYDROPHOBICALLY MODIFIED INULIN AND DDAB
J. Morros, M. R. Infante, M. G. Miguel, B. Lindman, R. Pons
92
O3.3
POLYMERIC NANO-EMULSIONS OBTAINED BY LOW-ENERGY
METHODS AND THEIR USE FOR NANOPARTICLE TEMPLATING.
M. Homs, G. Calderó, C. Solans
93
O3.4
STABLE CAPSULES FORMED BY LIPOSOMES COATED BY THE
LAYER-BY-LAYER METHOD.
R. G. Rubio, M. Ruano, F. Ortega
94
O3.5
SERINE-BASED CATANIONIC LIPOSOMES AS POTENTIAL
NANOCARRIERS FOR MOLECULAR DELIVERY
S. G. Silva, D. Félix, M. L. C. do Vale, E. F. Marques
95
O3.6
SOFT PARTICLES FOR TUNABLE NANOPHOTONICS
A. Maldonado-Valdivia, B. Sierra-Martín, A. Fernández-Barbero
96
CONTENTS
24
ORAL COMMUNICATIONS
4. Colloids and Energy
O4.1
A RHEOLOGICAL STUDY OF MAGNETIC FLUIDS BASED ON
HIGHLY VISCOELASTIC SOLVENTS
J. P. Segovia-Gutiérrez, R. Hidalgo-Álvarez, J. de Vicente
97
O4.2
BAND GAP ENGINEERING WITH SUBNANOMETRIC METAL (0)
CLUSTERS: CATALYTIC, ELECTROCATALYTIC &
PHOTOCATALYTIC APPLICATIONS
M. A. López-Quintela, N. Vilar-Vidal, D. Buceta, M. C. Blanco, J. Rivas
98
CONTENTS
25
ORAL COMMUNICATIONS
5. Surfaces and Interfaces
O5.1
NMR SELF-DIFFUSION STUDIES ON THE BINDING AND
EXCHANGE DYNAMICS BETWEEN BLOCK COPOLYMERS AND
CARBON NANOTUBES
R. Fernandes, M. Shtein, I. P. Bar, O. Regev, I. Furó, E. F. Marques
99
O5.2
PROBING IN-VITRO DIGESTION OF INTERFACIAL PROTEIN
STRUCTURES IN A SINGLE DROPLET
J. Maldonado-Valderrama, J. A. Holgado-Terriza, A. Torcello-Gómez, M. A.
Cabrerizo-Vílchez
100
O5.3
EFFECT OF POROSITY AND SURFACE MATERIAL IN THE
TRANSPORT OF IONS ACROSS NANOPOROUS ALUMINA
MEMBRANES
V. Romero, V. Vega, J. García, R. Zierold, K. Nielsch, V. M. Prida, B.
Hernando, J. Benavente
101
O5.4
BULK AND INTERFACIAL MICRORHEOLOGY
F. Ortega, L. J. Bonales, A. Maestro, N. Mancebo, F. Martínez-Pedrero, J. E.
Fernandez-Rubio, R. Chuliá, A. J. Mendoza, R. G. Rubio
102
O5.5
SEGREGATION OF SILICA PARTICLES WITH DIFFERENT SIZE
USING DRIVEN RECEDING CONTACT LINES
C. L. Moraila-Martínez, M. A.Cabrerizo-Vílchez, M. A. Rodríguez-Valverde
103
O5.6
IONS-INDUCED NANOSTRUCTURATION OF HYDROPHOBIC
POLYMER SURFACES
C. Drummond, I. Siretanu, D. Bastos, J.-P. Chapel
104
O5.7
QUANTUM DOTS ONTO POLYMER AND SURFACTANT SELFASSEMBLED FILMS: A QUARTZ CRYSTAL MICROBALANCE
STUDY
T. Alejo, M. D. Merchán, M. M. Velázquez
105
O5.8
SUDDEN FIELD INDUCED SUBLIMATION IN 2D COLLOIDAL
CRYSTALLITES
F. Martínez-Pedrero, J. E. Fernandez-Rubio, R. G. Rubio, F. Ortega
106
CONTENTS
26
ORAL COMMUNICATIONS
6. Modeling and Simulations
O6.1
STOCHASTIC DIFFUSION OF ISOTROPIC AND LIQUID CRYSTAL
PHASES OF RODLIKE COLLOIDAL PARTICLES: MONTE CARLO
AND BROWNIAN DYNAMICS MEET
A. Patti, A. Cuetos
107
O6.2
COARSE-GRAINED MONTE CARLO SIMULATIONS OF THERMORESPONSIVE POLYELECTROLYTE NANOGELS
M. Quesada-Pérez, J. A. Maroto-Centeno, A. Martín-Molina
108
O6.3
EFFECTIVE ELECTROSTATIC INTERACTIONS ARISING IN CORESHELL CHARGED MICROGEL SUSPENSIONS WITH ADDED SALT
A. Moncho-Jordá, J. A. Anta, J. Callejas-Fernández
109
O6.4
NON-RANDOM ADSORPTION OF POLYELECTROLYTES IN
REGULARLY CHARGED SURFACES. FROM SINGLE CHAIN TO
MULTICHAIN DEPOSITION
S. C. C. Nunes, T. Firmino, A. A. C. C. Pais
110
O6.5
A MOLECULAR INSIGHT ON NEW VESICULAR SYSTEMS
FORMED BY SELF-ASSEMBLY OF
STEROLS AND QUATERNARY AMMONIUM SURFACTANTS
J. Faraudo, L. Ferrer-Tasies, E. Moreno-Calvo, M. Cano-Sarabia, M. AguilellaArzo, A. Angelova, S. Lesieur, S. Ricart, N. Ventosa, J. Veciana
111
O6.6
INTERNAL AND FREE ENERGY IN A PAIR OF LIKE-CHARGED
COLLOIDS. CONFINED AND BULK FLUIDS.
A. Cuetos, J. A. Anta, A. Puertas
112
CONTENTS
27
ORAL COMMUNICATIONS
7. Biotechnological Applications
O7.1
MULTIPLEXED PLASMON SENSOR FOR RAPID LABEL-FREE
ANALYTE DETECTION
R. Ahijado-Guzmán, C. Rosman, J. Prasad, A. Neiser, A. Henkel, J. Edgar,
C. Sönnichsen
113
O7.2
DEVELOPMENT OF DODAB:MO LIPOSOMES FOR GENE
DELIVERY
J. P. N. Silva, A. C. N. Oliveira, A. F. C. Gomes, M. E. C. D. R. Oliveira
114
O7.3
USING AFM TO STUDY THE COMPLEXATION OF DNA AND
ANIONIC LIPID MEDIATED BY Ca2+ AT THE AIR-WATER
INTERFACE
G. Luque-Caballero, A. Martín-Molina, J. Maldonado-Valderrama
115
O7.4
GENE TRANSFER MEDIATED BY BIS-QUATERNARY GEMINI
SURFACTANTS DEPENDS ON COMPLEX ARCHITECTURE
A. M. Cardoso, C. M. Morais , S. G. Silva , M. L. do Vale, E. F. Marques,
M. C. P. de Lima, A. S. Jurado
116
CONTENTS
28
POSTERS SPECIAL SESSIONS
PSS01
LUMINISCENT/MAGNETIC LIPOSOMES WITH RGD-CONJUGATE
PEPTIDE FOR THERANOSTIC APPLICATIONS
M. A. Busquets, E. Escribano, J. Queralt, M. Sangrà, M. Gallardo, J. Estelrich
119
PSS02
INTERFACIAL ACTIVITY COMPARISON BETWEEN BARE,
HOMOGENEOUS AND JANUS GOLD NANOPARTICLES
M. A. Fernandez-Rodriguez, M. A. Rodriguez-Valverde, M. A. CabrerizoVilchez,Y. Song, S. Chen, A. Sánchez-Iglesias, L. M. Liz-Marzán, R.
Hidalgo-Alvarez
120
PSS03
GROWTH OF METAL SULFIDES ON POLYMER BEADS: A
STARTING POINT FOR NANOCAPSULES
M. C. Neves, M. M. Silva, D. Lopes, T. Trindade
121
PSS04
SYNTHESIS AND MODIFICATION OF METAL NANOPARTICLES
IN ORGANIC MEDIUM FOR PLASMONIC APPLICATIONS
L. Polavarapu, L. M. Liz-Marzán
122
PSS05
METALLIC JANUS PARTICLES
D. Rodríguez-Fernández, J. Pérez-Juste, I. Pastoriza-Santos, L. M. LizMarzán
123
PSS06
OIL-IN-WATER MICROEMULSIONS FOR THE SYNTHESIS OF
CeO2, CuO, AND CuO/CeO2 NANOPARTICLES AND THEIR USE AS
PHOTOCATALYSTS
M. Sánchez-Domínguez, A. V. Vela-Gonzalez, K. Pemartin, C. Solans, S. A.
Pérez-García, C. C. Leyva-Porras, I. Juárez-Ramírez
124
PSS07
PREPARATION OF ORGANIC SOLVENT RESISTANT
NANOCARRIERS FROM O/W NANO-EMULSIONS AS TEMPLATES
S. Vílchez-Maldonado, R. Molina, J. Esquena, G. Calderó
125
PSS08
INTERACTION BETWEEN A ZWITTERIONIC THIOPHENE BASED
CONJUGATED POLYELECTROLYTE AND SURFACTANTS IN
AQUEOUS SOLUTION
T. Costa, D. de Azevedo, M. Knaapila, A. Valente, M. Kraft, U. Scherf, H. D.
Burrows
126
PSS09
IONIZATION BY pH AND ANIONIC SURFACTANT BINDING
GIVES THE SAME THICKENING EFFECTS OF CROSSLINKED
POLYACRYLIC ACID DERIVATIVES
C. M. G. Duarte, L. Alves, F. E. Antunes, B. Lindman, B. Klotz, A. Böttcher,
H.-M. Haake
127
PSS10
THE INFLUENCE OF THE COMBINATION OF Fe(III) IONS WITH
BPEI AND LPEI IN DNA CONDENSATION: PHYSICO-CHEMICAL
CHARACTERIZATION AND IN VITRO CYTOTOXICITY TESTING
A. F. Jorge, M. C Morán, M. P. Vinardell, R. S. Dias, A. A. C. C. Pais
128
CONTENTS
29
PSS11
CHARACTERIZATION OF WATER/SODIUM DODECYL
SULPHATE/PROPANOL/ALLYLBENZENE MICELLAR SYSTEMS
M. Fanun
129
PSS12
INFLUENCE OF HUMIC ACIDS AS COLLOIDAL SYSTEMS ON
THE STABILITY OF XENOBIOTICS
J. C. Mejuto, J. Morales, O. Moldes, J. A. Manso
130
PSS13
DRUG DELIVERY SYSTEMS BASED ON DIACYL ARGININE
SURFACTANTS: PREPARATION, CHARACTERIZATION AND
EVALUATION OF THEIR BIOLOGICAL ACTIVITY
L. Pérez, L. Tavano, M. R. Infante, A. Pinazo, M. A. Manresa, M. P.
Vinardell, M. Mitjans
131
PSS14
STUDY OF THE STABILITY OF POLYETHYLENIMINEDECORATED LIPOSOMES
G. Prieto, J. Sabín, C. Vázquez-Vázquez, F. Bordi, F. Sarmiento
132
PSS15
NOVEL SERINE-BASED GEMINI SURFACTANTS FOR GENE
DELIVERY: PHYSICOCHEMICAL AND COMPACTION STUDIES
S. G. Silva, I. S. Oliveira, M. L. C. do Vale, E. F. Marques
133
PSS16
EFFECT OF THE ELECTROSTATIC INTERACTIONS IN THE
NANOPARTICLE PATTERNING USING DRIVEN EVAPORATING
MENISCI
D. Noguera-Marín, C. L. Moraila-Martinez, M. Cabrerizo-Vilchez, M. A.
Rodriguez-Valverde
134
PSS17
SURFACE ENHANCED RAMAN SCATTERING MICROSCOPY
WITH SUBSTRATES FABRICATED BY AU &AG “NANO-INKS”
S. M. Novikov, l. Polavarapu, L. M. Liz-Marzán
135
PSS18
SURFACE BEHAVIOR OF BINARY SYSTEMS CONSISTING OF
E1(70-87) PEPTIDE FROM HGV-C VIRUS AND VARIOUS
PHOSPHOLIPIDS
M. Pujol, A. Ortiz, M. Muñoz-Juncosa, J. Prat, V. Girona, M. A. Alsina
136
PSS19
OLIGOMER, PROTOFIBRILLAR AND FIBRILLAR AGGREGATES
FROM RECOMBINANT HUMAN LYSOZYME: SURFACE
PROPERTIES AND CYTOTOXIC EFFECT
E. D. Ruiz, G. Burboa, J. Juárez, P. Taboada, V. Mosquera, M. A. Valdes
137
PSS20
ON THE INITIAL-GAP DEPENDENCE OF
MAGNETORHEOLOGICAL PERFORMANCE UNDER SQUEEZING
FLOW
J. A. Ruiz-López, R. Hidalgo-Álvarez, J. de Vicente
138
CONTENTS
30
PSS21
HOW CHIRALITY MAY AFFECT TO THE SELF-AGGREGATION
PATTERN OF LYSINE-BASED CATIONIC GEMINI LIPIDS AND
THEIR INTERACTION WITH PLASMID DNA?
RIBBON-TYPE AND CLUSTER-TYPE LIPOPLEXES
A. L. Barrán-Berdón, M. Muñoz-Úbeda, C. Aicart-Ramos, L. Pérez, A.
Martín-Molina, P. Castro-Hartmann, E. Aicart, E. Junquera
139
PSS22
LIPID-POLOXAMER NANOEMULSIONS AS POTENTIAL
BIOLOGICAL CARRIERS
L. García-Jara, A. Martín-Rodríguez, J. A. Marchal-Corrales, Gema Jimenez,
J. M. Peula-García
140
PSS23
DODAC:MO:DC-CHOL/CHEMS LIPOPLEXES FOR GENE
DELIVERY
O. Gonçalves, H. Carvalho, J. P. N. Silva, A. C. Gomes, M. E. C. D. R.
Oliveira
141
PSS24
DEVELOPMENT AND CHARACTERIZATION OF FLUORESCENT
MICROSPHERES AS A PROBE FOR PARTICLE UPTAKE ASSAYS
BY FLOW CITOMETRY
C. Sóñora, A. Hernández, I. Miraballes- Martínez
142
CONTENTS
31
POSTERS
P01
HYBRID CORROLE-GOLD NANOPARTICLES
J. F. B. Barata, A. L. Daniel-da-Silva, M. Graça, P. M. S. Neves, J. A. S.
Cavaleiro, T. Trindade
145
P02
OPTIMIZATION OF A NANOSTRUCTURED LIPID CARRIERS
FORMULATION FOR PORPHYRIN DELIVERY BASED ON
FACTORIAL DESIGN
L. Damas, C. Vitorino, J. J. Sousa, M. Piñeiro, A. A. C. C. Pais
146
P03
CHITOSAN OR ALGINATE-COATED IRON OXIDE
NANOPARTICLES: A COMPARATIVE STUDY
J. Estelrich, J. Castelló, M. A. Gallardo, M. A. Busquets
147
P04
BROADBAND DIELECTRIC SPECTROSCOPY TO STUDY
COLLOIDAL MATERIALS
E. Galera-Cortés, J. D. Solier, J. Estelrich, R. Hidalgo-Álvarez
148
P05
CLEANING OF DRIED STARCH IN STAINLESS STEEL WITH
SURFACTANT SOLUTIONS CONTAINING MICRO- AND
NANOPARTICLES
E. Jurado, J. M. Vicaria, O. Herrera-Márquez, A. Plaza
149
P06
HYBRID MAGNETIC POLYMERIC NANOPARTICLES PREPARED
VIA MINIEMULSION POLYMERIZATION
C. Kaewsaneha, P. Tangboriboonrat, D. Polpanich, A. Elaissari
150
P07
SERS PERFORMANCE OF GOLD NANOSTARS
J. Langer, A. Shiohara, A. Sánchez-Iglesias, L. M. Liz-Marzán
151
P08
PS-PAA-CAPPED GOLD NANOSTARS AS SERS SUBSTRATE FOR
THE DETECTION OF HYDROPHOBIC MOLECULES
A. La Porta, A. Sánchez-Iglesias, M. Grzelczak, L. M. Liz-Marzán
152
P09
COMB-LIKE ACRYLIC-BASED POLYMER LATEXES
CONTAINING NANO-SIZED CRYSTALLISABLE DOMAINS
E. Mehravar, J. R. Leiza, J. M. Asua
153
P10
SYNTHESIS AND PHOTOCATALYTIC PROPERTIES OF
TITANATES NANOTUBES SENSITIZED BY CRYSTALLINE Ag2S
NANOPARTICLES
M. C. Neves, A. J. Silvestre, M. R. Nunes, O. C. Monteiro
154
P11
HIGHLY ORGANIZED PLASMONIC NANOPARTICLES:
UNIFORM PLASMONIC STRUCTURES AS SERS PLATFORMS
N. Pazos-Perez, M. Tebbe, R. Alvarez-Puebla, A. Fey
155
P12
FERROMAGNETIC ANISOTROPIC NANOSTRUCTURES FOR
AQUEOUS METAL IONS UPTAKE
P. C. Pinheiro, D. S. Tavares, A. L. Daniel-da-Silva, C. B. Lopes, E. Pereira,
J. P. Araújo, C. T. Sousa, T. Trindade
156
CONTENTS
32
P13
PAMAM DENDRIMERS EXERTED OXIDATIVE DAMAGE AND
STRUCTURAL ALTERATIONS IN GREEN ALGAE AND
CYANOBACTERIA
I. Rodea-Palomares, S. Gonzalo, F. Leganés, E. García-Calvo, F. FernándezPiñas, R. Rosal
157
P14
STERIC HINDRANCE INDUCES CROSS-LIKE SELF-ASSEMBLY
OF GOLD NANODUMBBELLS
A. Sánchez-Iglesias, M. Grzelczak, H. H. Mezerji, S. Bals, J. Pérez-Juste, L.
M. Liz-Marzán
158
P15
NOBLE METAL NANOPARTICLES COATED WITH MESOPOROUS
MATERIALS
M. N. Sanz-Ortiz, L. M. Liz-Marzán
159
P16
FORMATION OF PLASMONIC HETEROSTRUCTURES VIA
COVALENT BOND CHEMISTRY
A. B. Serrano-Montes, M. Grzelczak, L. M. Liz-Marzán
160
P17
VARIOUS STRATEGIES OF GOLD NANOSTAR SYNTHESIS FOR
SERS APPLICATIONS
A. Shiohara, L. M. Liz-Marzán
161
P18
A SIMPLE METHOD TO PREPARE SORBENTS BASED ON
MAGNETITE COATED WITH SILICEOUS HYBRID SHELLS FOR
THE REMOVAL OF NON-ESSENTIAL METAL IONS FROM
WATERS
D. S. Tavares, A. L. Daniel-da-Silva, C. B. Lopes, N. J. O. Silva, V. S.
Amaral, J. Rocha, E. Pereira, T. Trindade
162
P19
ANISOTROPIC GOLD/PLGA NANOHYBRIDS FOR CANCER
THERAPY AND IMAGING
A. Topete, A. Cambón, E. Vilar, M. Alatorre-Meda, S. Barbosa, S. CarregalRomero, W. Parak, P. Taboada, V. Mosquera
163
P20
THERMAL EFFECTS IN LOADED LIPID NANOPARTICLES
DISPERSION AND HYBRID MEMBRANES (POSTER,
NANOPARTICLES: ORGANIC, INORGANIC AND HYBRIDS)
M. I. Vazquez, J. Hierrezuelo, J. M. López-Romero, J. Benavente
164
P21
CONTROL OF THE AGGREGATION OF PRIMARY
NANOCRYSTALS DURING PARTICLE GROWTH: FROM SMOOTH
TO ROUGH MAGNETITE PARTICLES
F. Vereda, M. P. Morales, B. Rodríguez-González, J. de Vicente,
R. Hidalgo-Álvarez
165
P22
SYNTHESIS OF ZnO/Ag HYBRID NANOMATERIALS AND STUDY
OF THEIR ELECTRICAL PROPERTIES (POSTER, TOPIC:
NANOPARTICLES: ORGANIC, INORGANIC AND HYBRIDS)
G. Vidal-Lopez, K. Pemartin, C. Solans, A. Morales-Sanchez, M. SanchezDominguez
166
CONTENTS
33
P23
DESIGN OF A DUAL NANOSTRUCTURED LIPID CARRIERS
FORMULATION BASED ON PHYSICOCHEMICAL,
RHEOLOGICAL AND MECHANICAL PROPERTIES
C. Vitorino, L. Alves, F. E. Antunes, J. J. Sousa, A. A. C. C. Pais
167
P24
THERMODYNAMIC STUDY OF THE INTERACTION BETWEEN
5,10,15,20-TETRAKIS-(N-METHYL-4-PYRIDYL)PORPHYRIN
TETRAIODINE AND SODIUM DODECYL SULFATE: A
CONDUCTOMETRIC STUDY
C. M. R. Almeida, R. F. P. Pereira, B. F. O. Nascimento, M. Pineiro, A. J. M.
Valente
168
P25
RHEOLOGICAL STUDIES OF UNMODIFIED CELLULOSE
SOLUTIONS BASED ON NEW PROMISING ALKALI SOLVENT
SYSTEMS
L. Alves, C. Costa, F. Antunes, B. Medronho, B. Lindman
169
P26
NANOSTRUCTURING CONJUGATED POLYELECTROLYTES IN
TETRAETHYLENE GLYCOL MONODODECYL ETHER/WATER
LIQUID CRYSTALS
H. D. Burrows, M. Knaapila, S. M. Fonseca, B. Stewart, M. Torkkeli, J.
Perlich, S. Pradhan, U. Scherf
170
P27
A NOVEL APPROACH TO THE DEVELOPMENT OF UNMODIFIED
CELLULOSE SOLVENTS
C. Costa, L. Alves, F. Antunes, B. Medronho, M. G. Miguel, B. Lindman
171
P28
WATER-BORNE PRESSURE SENSITIVE ADHESIVES BASED ON
RENEWABLE PROTIC IONIC LIQUIDS
A. M. Fernandes, M. Moreno, A. Adboudzadeh, R. Gracia, M. J. Barandiaran,
D. Mecerreyes
172
P29
BIOMIMETIC TRIBLOCK COPOLYMER MEMBRANES:
FROM AQUEOUS SOLUTIONS TO SOLID SUPPORTS
A. González-Pérez, V. Castelletto, I. Hamley, A. Topete, E. Villar-Alvarez, N.
González, A. Cambón, S. Barbosa, P. Taboada, V. Mosquera
173
P30
SPECTROSCOPIC STUDY OF THE INTERACTION OF HECAMEG
WITH BOVINE SERUM ALBUMIN AND ITS EFFECT ON THE
PROTEIN CONFORMATION
J. M. Hierrezuelo, B. Nieto-Ortega, C. Carnero-Ruiz
174
P31
NOVEL STRUCTURAL CHANGES DURING TEMPERATUREINDUCED SELF-ASSEMBLING AND GELATION IN AQUEOUS
SOLUTIONS OF THE COPOLYMER PLGA1170-PEGN-PLGA1170
N. Khorshid, K. Knudsen, S. A. Sande, B. Nyström
175
P32
SYNTHESIS AND MINERALIZATION OF A POLYMERIC
NETWORK USING THE REACTION DIFFUSION METHOD
E. Lopez-Cabarcos, Y. Ramadan, J. Rubio-Retama
176
CONTENTS
34
P33
ADSORPTION OF POLYELECTROLYTE-SURFACTANT
MIXTURES OF COSMETIC INTEREST
S. Llamas, R. G. Rubio, F. Ortega, N. Baghdadli, G. Luengo, C. Cazeneuve
177
P34
MOLECULAR DYNAMICS SIMULATIONS OF SURFACTANT
MICELLES
V. I. Martín, L. J. Álvarez, M. L. Moyá
178
P35
SYNTHESIS AND PHYSICOCHEMICAL CHARACTERIZATION OF
ALKANEDYIL-BIS(DIMETHYLDODECYLAMMONIUM) BROMIDE,
12-S-12,2BR-, SURFACTANTS WITH S=7, 9 ,11 IN AQUEOUS
MEDIUM
V. I. Martín, A. Rodríguez, A. Maestre, M. L. Moyá
179
P36
A COMPARATIVE THERMODYNAMIC ANALYSIS OF CLOUDING
PHENOMENON IN MIXTURES OF SUGAR-BASED SURFACTANTS
WITH TRITON X-100
J. A. Molina-Bolívar, M. Naous, J. M. Hierrezuelo, C. Carnero-Ruiz
180
P37
MORPHOLOGICAL AND PROTEIN BINDING STUDIES IN LYSINEBASED SELF-ASSEMBLED NANO/MICRO-TUBES
I. S. Oliveira, M. J. Araújo, E. F. Marques
181
P38
SHAKE INDUCED GELATION OF PARTICLE-POLYMER
DISPERSIONS
R. Perea, M. M. Ramos-Tejada, P. Luckam
182
P39
PERMEABILITY-TUNABLE MICROGELS
B. Sierra-Martín, A. Maldonado-Valdivia, A. Fernández-Barbero
183
P40
RATIONAL DESIGN OF CLEAVABLE CATIONIC GEMINI
SURFACTANTS: EXPLORING THE MULTIFUNCTIONALITY OF
SERINE AS HEADGROUP
S. G. Silva, C. Alves, A. M. S. Cardoso, A. S. Jurado, M. C. P. Lima, M. L. C.
do Vale, E. F. Marques
184
P41
KINETICS AND MECHANISMS OF THERMAL DEGRADATION OF
WATER BORNE poly(BA/MMA)/GRAPHENE COMPOSITES
D. Spasevska, A. Arzac, J. Blazevska-Gilev, R. Fajgar, R. Tomovska
185
P42
POLY(N-VINYLCAPROLACTAM) NANOGELS: A LIGHT
SCATTERING STUDY
J. Callejas-Fernández, J. Ramos, A. Imaz, J. Forcada, M. Quesada-Pérez, A.
Moncho-Jordá
186
P43
NEW SORBENTS BASED ON SILICA-CARRAGEENAN HYBRIDS
R. S. Carvalho, D. S. Tavares, A. L. Daniel-da-Silva, T. Trindade
187
P44
LYSINE BASED CATIONIC SURFACTANTS AT THE AIR-WATER
INTERFACE. MIXED MONOLAYERS WITH DPPC: AN
INVESTIGATION INTO THE ANTIMICROBIAL ACTIVITY
A. Colomer, L. Perez, M. R. Infante, R. Pons, A. Manresa, M. J. Espuny, A.
Pinazo
188
CONTENTS
35
P45
SUPRAMOLECULAR AGGREGATION IN CATIONIC/ANIONIC
MIXTURES OF CALIXARENE AND SERINE-BASED
SURFACTANTS
C. Costa, V. Francisco, M. L. C. do Vale, L. Garcia-Rio, E. F. Marques
189
P46
THE ROLE OF THE IONIC SPECIFICITY ON THE NANOGEL
AGGREGATION
V. D. G. González, D. Bastos-González, J. Callejas-Fernández, M. TiradoMiranda
190
P47
RHAMNOLIPID CHARACTERIZATION AND ITS INFLUENCE ON
DPPC BILAYER ORGANIZATION
E. Haba, R. Pons, L. Pérez, A. Manresa, A. Pinazo
191
P48
STRUCTURE AND PLASMON COUPLING OF 2D Au@PNIPAM
MICROGEL ARRAYS WITH THERMALLY CONTROLLED
INTERPARTICLE GAP
A. Maldonado-Valdivia, J. Clara-Rahola, R. Contreras-Cáceres, B. SierraMartín, A. Fernández-Barbero
192
P49
INFLUENCE OF XENOBIOTICS ON THE STABILITY OF NATURAL
MICELLAR AGGREGATES
J. Morales, J. A. Manso, M. Arias-Estevez, J. C. Mejuto
193
P50
STABILITY OF CARBOFURAN IN RESTRICTED AQUEOUS MEDIA
J. Morales, J. A. Manso, A. Cid, M. A. Iglesias-Otero, J. C. Mejuto
194
P51
EFFECT OF MIXED CROWDING MEDIA ON THE DIFFUSION OF
ALPHA-CHYMOTRYPSIN
I. Pastor, E. Vilaseca, S. Madurga, J. L. Garcés, M. Cascante, F. Mas
195
P52
STABILITY OF THE POLYMER LAYERS FORMED BY THE
LAYER-BY-LAYER METHOD
R. Perea, M. M. Ramos-Tejada, K. Rudzka, A. V. Delgado
196
P53
OSTWALD RIPENING INHIBITION OF CONCENTRATED
LIMONENE EMULSIONS
L. M. Pérez-Mosqueda, P. Ramírez, J. Muñoz
197
P54
STUDIES ON THE COLLOIDAL STABILITY OF F-DPPC AND DPPC
LIPOSOMES. THE INFLUENCE OF CA2+ AND THE INTERDIGITED
BILAYER ON THE AGGREGATION PROCESS
G. Prieto, P. Toimil, R. Daviña, F. Sarmiento
198
P55
MICROFLUIDIC SYNTHESIS OF SILICONE CAPSULES FOR
ENCAPSULATION AND RELEASE APPLICATIONS
N. Vilanova, C. Rodríguez-Abreu, A. Fernández-Nieves, C. Solans
199
P56
CONTACT ANGLE HYSTERESIS OF COMMERCIALLY PURE
TITANIUM SURFACES FUNCTIONALIZED WITH
ORGANOPHOSPHONATES
D. Blasco-Avellaneda, A. Y. Sánchez-Treviño, M. A. Rodríguez-Valverde,
M. A. Cabrerizo-Vílchez
200
CONTENTS
36
P57
SELF-ASSEMBLED 2D ARRAYS OF Au NANOPARTICLES
J. J. Giner-Casares, L. M. Liz-Marzán
201
P58
LIPID SPECIFICITY FOR THE INTERACTION OF A NOVEL
ANTIMICROBIAL PEPTIDE SP85 WITH MODEL MEMBRANES
A. Grau-Campistany, M. Pujol, F. Rabanal, Y. Cajal
202
P59
NAPHTHENIC BITUMEN-CALCITE AGGREGATE WETTABILITY
AT HIGH TEMPERATURE
F. Guerrero-Barba, J. E. Arellano-Varela, M. A. Cabrerizo-Vílchez, M. A.
Rodríguez-Valverde
203
P60
SURFACE TENSIONS AND ACTIVITY COEFFICIENTS FOR
AQUEOUS SOLUTIONS OF LAURYL ETHER ETHOXYLATES
J. L. López-Cervantes, J. Gracia-Fadrique, E. Acosta, E. Calvo, A. Amigo
204
P61
MODULATION OF FILM MORPHOLOGY AT NANOSCALE BY
DIPPING, LANGMUIR-BLODGETT AND LANGMUIR-SCHAEFER
M. D. Merchán, T. Alejo, M. M. Velázquez
205
P62
IMPLICATION OF A PEPTIDE SEQUENCE FROM GB VIRUS C IN
THE INHIBITION OF HIV FUSION PEPTIDE
M. Muñoz, J. Prat, M. A. Busquets, M. Pujol, A. Ortiz, O. Domènech, M. A.
Alsina, V. Girona
206
P63
STUDY OF THE BEHAVIOR OF POLY(NIPAM) MICROGELS
UNDER IONIC SPECIFIC CONDITIONS: ELECTROKINETIC AND
AFM MEASURES
L. Pérez-Fuentes, C. Drummond, D. Bastos-González
207
P64
PROPERTIES OF CHITOSAN-INSULIN COMPLEXES OBTAINED
BY AN ALKYLATION REACTION ON CHITOSAN
E. Robles, J. Juárez, M. Alatorre-Meda, M. G. Burboa, P. Taboada, V.
Mosquera, M. A. Valdez
208
P65
FROM 2D TO 3D AT THE AIR/WATER INTERFACE: THE SELFAGGREGATION OF THE ACRIDINE DYE IN MIXED
MONOLAYERS
C. Rubia-Payá, E. Jimenez-Millán, J. J. Giner-Casares, G. Brezesinski, M. T.
Martín-Romero, L. Camacho
209
P66
IN-SITU MONITORING OF BIOMIMETIC HYDROXYAPATITE
GROWTH ON FUNCTIONALIZED TITANIUM SURFACES: AN AFM
STUDY
A. Y. Sánchez-Treviño, M. A. Fernandez-Rodríguez, M. A. RodríguezValverde, M. A. Cabrerizo-Vílchez
210
P67
USING ARTIFICIAL INTELLIGENCE BASED TOOLS FOR
PREDICTING THE CMC OF NON-IONIC SURFACTANTS
G. Astray, O. A. Moldes, M. A. Iglesias-Otero, J. C. Mejuto
211
CONTENTS
37
P68
A NUMERICAL TOOL FOR ANALYZING EQUILIBRIUM
CAPILLARY RISE
D. Blasco-Avellaneda, A. Amirfazli, M. A. Rodríguez-Valverde, M. A.
Cabrerizo-Vílchez
212
P69
SELF-ASSEMBLY OF A LONG-CHAIN IONIC SURFACTANT AT
LOW CONCENTRATIONS: A SIMULATION STUDY
J. Burgos, C. Solans, A. Patti
213
P70
BALANCE HIDROFÍLICO-LIPOFÍLICO HLBTR. ESCALA
TERMODINÁMICA
J. Gracia-Fadrique, J. L. López-Cervantes, F. D. Sandoval-Ibarra, A. AmigoPombo
214
P71
COMPUTATIONAL TOOLS FOR FORECASTING THE EFFECT OF
SMALL ORGANIC MOLECULES UPON ELECTRIC
PERCOLATION OF AOT-BASED MICROEMULSIONS
O. A. Moldes, G. Astray, A. Cid, J. C. Mejuto
215
P72
DOES INCUBATION TIME AFFECT THE FORMATION OF THE
PROTEIN CORONA?
A. L. Barrán-Berdón, D. Pozzi, G. Caracciolo, A. L. Capriotti, G. Caruso, C.
Cavaliere, A. Riccioli, S. Palchetti, A. Laganà
216
P73
THE EFFECT OF FLUORINATED CHOLESTEROL DERIVATIVE
ON THE STABILITY AND PHYSICAL PROPERTIES OF CATIONIC
DNA VECTORS
A. Martín-Molina, D. Paiva, I. Cardoso, M. Quesada-Pérez, M. d. C. Pereira,
S. Rocha
217
P74
BIONANOPARTICLES
A. Pikabea, G. Aguirre, A. Imaz, J. Ramos, J. Forcada
218
P75
SYNTHESIS AND CHARACTERIZATION OF DEGRADABLE AND
BIOCOMPATIBLE POLY(E-AMINO ESTER)-DNA COMPLEXES
A. Rata-Aguilar, J. L. Ortega-Vinuesa, A. B. Jódar-Reyes, A. MartínRodríguez, N. Segovia-Ramos, V. Ramos-Pérez, S. Borrós
219
P76
SILICON COLLOIDS BASED APPLICATIONS TO BIOSENSING
AND SUN RESISTANT MATERIALS
I. Rodriguez, R. Fenollosa, F. Meseguer
220
P77
SURFACE MODIFICATION OF LIPID NANOPARTICLES USING
POLOXAMER 407 SURFACTANT. EFFECTS ON CELLULAR
UPTAKE
P. Sánchez-Moreno, J. L. Ortega-Vinuesa, J. A. Marchal-Corrales, A. Salvati,
K. A. Dawson, J. M. Peula-García
221
CONTENTS
38
P78
222
RATIONALE DESIGN OF NANOEMULSIONS FOR THE DELIVERY
OF HYDROPHOBIC BIOACTIVE COMPOUNDS: FROM
SURFACTANTS AND INTERFACES TO IN VIVO RESULTS
M. Wulff-Pérez, A. Martín-Rodríguez, J. de Vicente, A. Serrano, F. J. Pavón,
M. J. Gálvez-Ruíz
PLENARY LECTURES
PLENARY LECTURES
41
PL1
Liquid crystalline superatoms
T. Lopez-Leon1,*, C. Blanc2, M. Nobili2 and A. Fernandez-Nieves3
1
ESPCI-ParisTech, UMR CNRS Gulliver 7083, F-75005 Paris, France.
Université de Montpellier II, UMR CNRS L2C 5221, F-34095 Montpellier, France.
3
Georgia Institute of Technology, School of Physics, Atlanta, Georgia 30332, USA.
*
[email protected]
2
In many aspects, colloids behave as big atoms [1]; however, the usual absence of
directionality in the interaction between colloids has limited the complexity of the structures
that they can spontaneously form [2]. As a result, low-coordination structures, common in
atomic and molecular systems, are rare in the colloidal domain. One way to address this is to
exploit the anisotropy that spontaneously arises when a colloidal particle is coated by a
nematic liquid crystal. In this spherical geometry, the orientational molecular order of the
nematic liquid crystal is disrupted by the presence of singularities or topological defects,
which appear symmetrically organized on the particle surface. These topological defects are
not only mathematic concepts, but also high energy spots suitable for chemical attack that
could be functionalized with ligands and act as attractive patches between particles [3,4]. The
number and arrangement of these defects can vary, providing flexibility for tuning directional
interactions. We have recently shown that these defects can be engineered to emulate the
linear, trigonal and tetrahedral geometries of sp, sp2, and sp3carbon bonds [5]. These
symmetries represent just a small sample of the variety of configurations that we can generate
by tuning parameters such as shell geometry, temperature, or symmetry of the liquid crystal
phase, which has revealed a vast playground for the formation of complex colloidal
superlattices [5,6].
[1] Poon, W., Science, 2004, 304, 830-831.
[2] Nelson E. C.; Braun P. V., Science, 2007, 328, 924-925.
[3] DeVries, G. A.; Brunnbauer, M.; Hu, Y.; Jackson, A. M.; Long, B.; Neltner, B. T.; Uzun, O;
Wunsch, B. H.; Stellacci, F., Science, 2007, 315, 358-361
[4] Gharbi, M. A.; Se, D.; Lopez-Leon, T.; Nobili, M.; Ravnik, M.; Žumer, S.; Blanc, C., Soft Matter,
2013, in press.
[5] Lopez-Leon, T.; Koning, V.; Devaiah, K. B. S.; Vitelli, V.; Fernandez-Nieves, A. Nature Phys.,
2011, 7, 391-394.
[6] Lopez-Leon, T.; Fernandez-Nieves, A.; Nobili, M.; Blanc, C. Phys. Rev. Lett., 2011, 106, 247802.
PLENARY LECTURES
42
PL2
Molecular engineering of Inorganic and Hybrid Nanostructured Materials
Clément Sanchez*
Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris, CNRS, Université Pierre
et Marie Curie. Collège de France, 11 Place Marcelin Berthelot, Bâtiment D. 75231, Paris, France.
*
[email protected]
Hybrid inorganic-organic materials can be broadly defined as synthetic materials
with organic and inorganic components which are intimately mixed. They can be either
homogeneous systems derived from monomers and miscible organic and inorganic
components, or heterogeneous and phase-separated systems where at least one of the
components’ domains has a dimension ranging from a few Å to several nanometers. Hybrid
phases can also be used to nanostructure or texture new inorganic nanomaterials (porous or
non porous). The mild synthetic conditions provided by the sol-gel process such as metalloorganic precursors, low processing temperatures and the versatility of the colloidal state
allow for the mixing of the organic and inorganic components at the nanometer scale in
virtually any ratio. These features, and the advancement of organometallic chemistry and
polymer and sol-gel processing, make possible a high degree of control over both
composition and structure (including nanostructure) of these materials, which present tunable
structure-property relationships. This, in turn, makes it possible to tailor and fine-tune
properties (mechanical, optical, electronic, thermal, chemical…) in very broad ranges, and to
design specific systems for applications. Hybrid materials can be processed as gels,
monoliths, thin films, fibers, particles or powders or can be intermediates to design materials
having complex shapes or hierarchical structures. The seemingly unlimited variety, unique
structure-property control, and the compositional and shaping flexibility give these materials
a high potential in catalysis, biocatalysis, photocatalysis, etc…. This lecture will describe
some recent advances on the chemistry and processing of nanostructured and hierarchically
structured functional inorganic and hybrid solids. Some of their properties will be discussed.
A few recent reviews:
x
x
x
x
x
x
x
x
x
x
Aerosol Route to Functional Nanostructured Inorganic and Hybrid Porous Materials. Boissiere, C.; Grosso, D.;
Chaumonnot, A.; et al., Adv. Mater., 2011, 23, 599-623
Applications of advanced hybrid organic-inorganic nanomaterials: from laboratory to market. Sanchez, C.;
Belleville, P.; Popall, M.; et al., Chem Soc. Rev., 2011, 40, 696-753
Molecular and supramolecular dynamics of hybrid organic-inorganic interfaces for the rational construction of
advanced hybrid nanomaterials. Grosso, D.; Ribot, F.; Boissiere, C.; et al., Chem. Soc. Rev., 2011, 40, 829-848
Design and properties of functional hybrid organic-inorganic membranes for fuel cells. Laberty-Robert, C.; Valle,
K.; Pereira, F.; et al. Chem. Soc. Rev., 2011, 40, 961-1005
Titanium oxo-clusters: precursors for a Lego-like construction of nanostructured hybrid materials. Rozes, L.;
Sanchez, C., Chem. Soc. Rev., 2011, 40, 1006-1030
Bio-inspired synthetic pathways and beyond: integrative chemistry. Prouzet, E.; Ravaine, S.; Sanchez, C.; et al.,
New J. Chem., 2008, 32, 1284-1299
Design, synthesis, and properties of inorganic and hybrid thin films having periodically organized nanoporosity.
Sanchez, C.; Boissiere, C.; Grosso, D.; et al., Chem. Mater., 2008, 20, 682-737
Inorganic and hybrid nanofibrous materials templated with organogelators. Llusar, M.; Sanchez, C., Chem.
Mater., 2008, 20, 782-820
Photonic and nanobiophotonic properties of luminescent lanthanide-doped hybrid organic- inorganic materials.
Escribano, P.; Julian-Lopez, B.; Planelles-Arago, J.; et al., J. Mater. Chem., 2008, 18, 23-40
Biomimetism and bioinspiration as tools for the design of innovative materials and systems. Sanchez, C; Arribart,
H.; Guille, M. M. G., Nature Mater., 2005, 4, 277-288
PLENARY LECTURES
43
PL3
Inorganic nanocrystals as functional building units for composites
Tito Trindade*
Department of Chemistry-CICECO, Aveiro Institute of Nanotechnology,
University of Aveiro, 3810-193 Aveiro, Portugal
*
[email protected]
Among the diversity of nanomaterials available nowadays, this
lecture will focus on the design of functional nanocomposites
containing inorganic phases. In order to prepare these composites,
the general approach followed in our research group merges
concepts from inorganic synthesis and colloidal chemistry. Thus
colloidal inorganic nanocrystals and metal complexes will be
presented here as functional compounds that confer specific
properties to composite materials obtained by diverse chemical
strategies. First, organically capped metal nanocrystals will be
described as adequate fillers to produce nanocomposites based on
synthetic polymers, while hydrophilic nanoparticles will be
presented as convenient fillers to produce biocomposites of natural
matrices. The second part of the presentation will discuss the
synthesis of hybrid silica particles containing inorganic
compounds, such as metal complexes and metal oxides, aiming to
confer specific functionalities to the final nanoparticles. Selected
examples of materials prepared by the strategies mentioned above
will illustrate their interest for biological (e.g. clinical diagnostics)
and environmental (e.g. water purification) applications.
Figure caption: From inorganic nanocrystals to composites
The author thanks Fundação para a Ciência e Tecnologia (PTDC/CTM-NAN/120668/2010 and PestC/CTM/LA0011/2011), FSE and POPH for funding.
INVITED LECTURES
INVITED LECTURES
47
I1
Biomolecular hydrogels – nature's playground for supramolecular chemistry
and physics
Ralf P. Richter*
CIC biomaGUNE, Biosurfaces Unit, Donostia - San Sebastian, Spain; J. Fourier Univeristy, Department
of Molecular Chemistry, Grenoble, France; Max Planck Institute for Intelligent Systems, Stuttgart,
Germany
*
[email protected]
Nature has evolved complex materials that are exquisitely designed to perform
specific functions. Certain proteins and glycans self-organize in vivo into soft and dynamic,
strongly hydrated gel-like matrices. Illustrative examples of such biomolecular hydrogels are
cartilage or mucus. Even though biomolecular hydrogels are ubiquitous in living organisms
and fulfill fundamental biological tasks, we have today a very limited understanding of their
internal organization, and how they function. The main reason is that this type of assemblies is
difficult to study with conventional biochemical methods.
In order to study biomolecular hydrogels directly on the supramolecular level, we
have developed an unconventional approach that draws on knowledge from several scientific
disciplines. Exploiting surface science tools, we tailor-make model systems by directed selfassembly of purified components on solid supports. With a toolbox of biophysical
characterization techniques, including QCM-D, ellipsometry, AFM and RICM, these model
films can be investigated quantitatively and in great detail. The experimental data, combined
with polymer theory, allow us to develop a better understanding of the relationship between
the supramolecular organization and dynamics of biomolecular hydrogels, their physicochemical properties and their biological function.
To illustrate this concept, I will present a few examples of our recent research. They
relate to (i) a nanoscopic protein hydrogel inside living cells that is responsible for the
regulation of macromolecular transport into and out of the nucleus [1,2], and (ii) microscopic
hydrogel-like assemblies that are made from the polysaccharide hyaluronan and hyaluronanbinding proteins and that are involved in various physiopathological process such as
inflammation, fertilization, cancer progression and immune response [3-5]. Our results may
ultimately prove useful for the development of novel bioinspired devices, such as size and
species selective filtration devices, or advanced biosensors, and for the development of novel
diagnostic or therapeutic methods.
Acknowledgements: This work was supported by the Spanish Ministry of Economy and Competitiveness
(refs. RYC2009-04275 and MAT2011-24306), the Department of Industry of the Basque Government,
the German Federal Ministry of Education and Research (ref. 0315157) and the European Research
Council (Starting Grant, ref. 306435).
[1] Eisele, N. B.; Frey, S.; Piehler, J.; Görlich, D.; Richter, R. P. EMBO Rep. 2010, 11, 366-372.
[2] Eisele, N. B.; Andersson, F. I.; Frey, S.; Richter, R. P. Biomacromolecules 2012, 13, 2322-2332.
[3] Richter, R. P.; Hock, K. K.; Burkhartsmeyer, J.; Boehm, H.; Bingen, P.; Wang, G.; Steinmetz, N. F.;
Evans, D. J.; Spatz, J. P. J. Am. Chem. Soc. 2007, 127, 5306-5307.
[4] Baranova, N. S.; Nilebäck, E.; Haller, F. M.; Briggs, D. C.; Svedhem, S.; Day, A. J.; Richter, R. P. J.
Biol. Chem. 2011, 286, 25675-25686.
[5] Attili, S.; Borisov, O. V.; Richter, R. P. Biomacromolecules 2012, 13, 1466-1477.
INVITED LECTURES
48
I2
Biosurfactants: Powerful Tools in Microbial Enhanced Oil Recovery
Lígia R. Rodrigues1,*, Eduardo J. Gudiña1 and J. A. Teixeira1
1
IBB – Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of
Minho, Braga, Portugal.
*
[email protected]
Currently, oil represents a crucial source of energy and one of the main drivers of the World
economy. Its recovery involves a primary phase that uses the natural pressure drive of the reservoir to
produce oil and gas; and a secondary phase that comprises the stimulation of oil wells by injecting fluids
to improve the flow of oil and gas to the well-head. However, after these two phases, up to two-thirds of
the original oil in place still remains in the reservoir [1]. This poor recovery is due to the low
permeability of some reservoirs, the high viscosity of the residual oil limiting its mobility, and the high
interfacial tension between the hydrocarbon and aqueous phases which results in high capillary forces
that retain the oil in small pores with the reservoir [2]. Therefore, extracting the maximum amount of oil
from mature reservoirs is a major challenge of the oil industry. Recovering the entrapped oil involves the
use of expensive chemical and thermal tertiary processes. Chemical processes include the use of
surfactants, polymers, acids, gases and solvents [1]. These chemicals have distinct roles in the recovery
processes, such as the decrease of interfacial tension between oil-water and oil-rock interfaces, thus
decreasing capillary forces and altering the wettability of the reservoir rock (surfactants); the increase of
water viscosity in flooding operations and the plugging of oil-depleted zones (polymers); the increase of
permeability through the porous network (acids); the decrease of oil viscosity and promotion of its flow
(gases and solvents). Microbial Enhanced Oil Recovery (MEOR) is an alternative tertiary oil recovery
process, with less costs and lower impact on the environment, in which microbial metabolites (biomass,
biopolymers, gases, acids, solvents, enzymes and biosurfactants) are used to improve the oil recovery
from mature reservoirs [1]. Biosurfactants are a heterogeneous group of surface-active molecules
produced by microbes with both hydrophilic and hydrophobic domains, which allow them to partition at
the interface between fluid phases with different degrees of polarity, reducing surface and interfacial
tensions. The most popular biosurfactants are the lipopeptides (from Bacillus species) and the
rhamnolipids (from Pseudomonas species) [3-5]. These compounds can efficiently replace synthetic
surfactants in oil recovery operations due to their specific activity, low toxicity, high biodegradability
and effectiveness under extreme operational conditions. Two main strategies can be adopted for the use
of biosurfactants in enhanced oil recovery. Biosurfactants can be produced ex situ and subsequently
injected into the reservoir; or they can be produced in situ by indigenous or injected microorganisms,
stimulated by the addition of selected nutrients into the well. The first strategy is expensive due to the
capital required for bioreactor operation, product purification and introduction into oil containing rocks;
while the second option is more favorable from an economic point of view, but requires the use of
microorganisms capable of producing sufficient amounts of biosurfactant within the reservoir [4]. In our
group, several suitable microorganisms for MEOR applications have been isolated from crude oil
samples and screened for biosurfactant production and ability to degrade heavy oil fractions. These have
been further characterized and used in bench-scale models that simulate the common oil recovery
operations.
Acknowledgements: This work was supported by PARTEX OIL AND GAS.
[1] Brown, L. R., Curr. Opin. Microbiol., 2010, 13, 316-320.
[2] Sen, R., Prog. Energy Combust. Sci., 2008, 34, 714-724.
[3] Simpson, D. R.; Natraj, N. R.; McInerney, M.J.; Duncan, K. E., Appl. Microbiol. Biotecnol., 2011, 91, 1083-1093.
[4] Gudiña, E. J.; Pereira, J. F. B.; Rodrigues, L. R.; Coutinho, J. A. P.; Teixeira, J. A., Int. Biodeterior. Biodegrad.,
2012, 68, 56-64.
[5] Pereira, J. F. B; Gudiña, E. J.; Dória, M. L.; Domingues, M. R.; Rodrigues, L. R.; Teixeira, J. A.; Coutinho, J. A.
P., Eur. J. Mass Spectrom., 2012, 18, 399-406.
INVITED LECTURES
49
I3
Effect of charge mobility and chain length on the adsorption of poly-acids on
oppositely charged nanoparticles. A Monte Carlo simulation
Rita S. Dias*
Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway.
*
[email protected]
Systems comprising of nanoparticles and oppositely charged polyelectrolytes have a great
technological interest, being major components in formulations used in pharmaceutical, food,
cosmetics, detergents, and paint industries. The stability of colloidal suspensions and the
interaction of its constituents are important issues in formulations, and a large effort has been made
to understand how the properties of each individual component affect the overall characteristics of
the formulations.
Within the class of polyelectrolytes, weak polyelectrolytes are very interesting since their
properties can be tunned resorting to pH variations. An additional characteristic of weak
polyelectrolytes is the fact that protons can migrate along the chains, between different chains, and
between the medium and the polyions [1]. It has been shown, using experimental and theoretical
tools, that the mobility of charges in many different systems enhances the interaction between
oppositely charged species. Examples are the adsorption of DNA [2-4] and proteins [5,6] onto lipid
membranes and the interaction between annealed polyacids and micelles [7,8].
In this work we have systematically studied the effect of charge mobility (quenched vs.
annealed) on the adsorption of polyacids to a nanoparticle and, additionally, on the interaction
between different nanoparticles. Two different architectures were considered for the quenched
polyacids, alternating and diblock, and two modes of charge mobility were considered for the
annealed polyacids, intra- and inter-chain mobility. The effect of polyacid chain length was also
evaluated.
Figure caption: Left: Distribution of the absolute value of the charge along the polyacid chains for a system with 30
segments, a charge fraction of 0.5, and intra-chain charge mobility in the presence (full curve) and absence (dashed
curve) of a nanoparticle. Right: Positioning maps of the adsorbed negatively charged (left-hand side) and neutral
(right-hand side) segments of the polyacids on the facing sides of the nanoparticles, placed at a separation of 1 Å.
Middle: Representative snapshot.
[1] Srivastava, D. K.; Wang, S.; Peterson, K. L. Biochemistry 2007, 36, 6359-6366.
[2] Maier, B.; Radler, J. O. Macromolecules 2000, 33, 7185-7194.
[3] Dias, R. S.; Pais, A. A. C. C.; Linse, P.; Miguel, M. G.; Lindman, B. J. Phys. Chem. B 2005, 109, 11781-11788.
[4] Dias, R. S.; Pais, A. A. C. C. J. Phys. Chem. B 2012, 116, 9246-9254.
[5] Denisov, G.; Wanaski, S.; Luan, P.; Glaser, M.; McLaughlin, S. Biophys. J. 1998, 74, 731-744.
[6] Dias, R. S.; Linse, P. Biophys. J. 2008, 94, 3760-3768.
[7] Norrman, J.; Lynch, I.; Piculell, L. J. Phys. Chem. B 2007, 111, 8402-8410.
[8] Ulrich, S.; Seijo, M.; Languecir, A.; Stoll, S. J. Phys. Chem. B 1997, 110, 20954-20964.
INVITED LECTURES
50
I4
The fluctuation theorem in dense colloids: A simulation study
Antonio M. Puertas*
Group of complex fluids physcis, Applied Physics, Universidad de Almeria, 04120 Almeria, SPAIN
*
[email protected]
The fluctuation theorem (FT) gives the distribution of work performed by an external
forcing in microscopic dissipative systems (e.g. Brownian particles) [1]. Interestingly, the
distribution extends to negative works, i.e. the system exerts work onto the external forcing,
violating the Second Law of Thermodynamics, although the maximum work is always in
positive work. This also implies a distribution of the entropy, which also extends to negative
values. The standard Second Law of Thermodynamics is recovered by taking large systems
and time intervals. In colloids, experiments and simulations have demonstrated the validity of
the FT by dragging a single particle through a viscous medium.
In this work, I will present simulations of a dense system of quasi-hard colloids
where a tracer of the same size as the bath particles is trapped in a harmonic potential and
dragged through the system at a constant velocity. The distribution of work done by the
harmonic trap is calculated, and studied with effective parameters for the colloidal bath,
namely the system viscosity and temperature of the colloidal bath, which can be also
determined from the steady state position distribution of the tracer inside the trap. The
necessity of effective parameters reveals the complex dynamics of the tracer, which is also
studied in detail, using tracer position correlation functions. The results for the effective
parameters and dynamics of the tracer are compared with experiments, confirming the general
results obtained by the simulations. Different types of forcings can be used, providing
qualitatively the same results.
Figure caption: Slice of the three dimensional system containing the tracer (marked in red), moving to
the right.
In conclusion, we show how microrheology experiments or simulations can provide
measurements of the viscosity of a colloidal system, but also the dynamics of the tracer
reflects the dynamics of the bath, which becomes increasingly complex as the glass transition
is approached.
[1] Evans, D. J.; Cohen, E. G. D.; Morris, G. P. Phys. Rev. Lett., 1993, 71, 2401.
INVITED LECTURES
51
I5
The Ion Specificity on Colloidal Systems
Delfi Bastos-González1,*, Leonor Pérez-Fuentes1, Carlos Drummond2 and Jordi Faraudo3
1
Grupo de Física de Fluidos y Biocoloides, Departamento de Física Aplicada, Facultad de Ciencias,
Universidad de Granada, Granada 18071 (Spain).
2
CNRS, Centre de Recherche Paul Pascal (CRPP),Bordeaux, France.
3
Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus de la UAB, E-08193 Bellaterra,
Barcelona, Spain
*
[email protected]
In this contribution, I am going to present the current state of the art of Hofmeister
effects or ion specificity on aqueous colloidal interfaces. I will specially highlight our
contributions in this research field, analyzing the most significant published data and also
some new experiments and simulations will be discussed.
It is widely known that different monovalent ions are able to specifically modify a
broad range of interfacial phenomena from surface tensions to colloidal stability by means of
accumulation or exclusion of the ions from the interfaces that cannot be explained just by
considering electrostatic interactions. These ionic specificities are commonly known as
Hofmeister effects [1]. They are universal phenomena present in biology, biochemistry,
chemistry and chemical engineering, colloid and surface science, and, even though they were
observed for the first time in 1888, their origin is still a matter of debate. In addition, with very
few exceptions, cations and anions consistently order with the same sequence, called the
Hofmeister series, regardless of the property studied. It is most recently accepted that to
explain ion specificity in Colloidal Systems is mandatory to consider not only the nature of the
ions but also the nature of the surfaces that interact with the ions [2-5]. Different results
coming from experiments and simulations show that the interaction of monovalent ions with
interfaces is dominated by solvation thermodynamics, this is the chaotropic/kosmotropic
character of ions and the hydrophobic/hydrophilic character of the surfaces [6,7]. These
conclusions are further emphasize when soft colloidal systems instead of hard particles are
used to analyze Hofmeister effects [8,9].
Acknowledgements: The authors acknowledge the financial support from projects MAT2009-13155C04-02, MAT2012-3670-C04-02 (Ministerio de Educación y Cultura (Spain)), P10-CTS-6270 (Junta de
Andalucía) and CEIBioTic 20F12/16.
[1] Hofmeister, F., Arch.Pathol. 1888, 24, 247.
[2] Kunz, W., Curr. Opin. Colloid Interface, 2010, 15, 34.
[3] López-León, T.; Santander-Ortega, M. J.; Ortega-Vinuesa, J. L.; Bastos-González, D., J. Phys. Chem.
C. 2008, 112, 16060.
[4] López-León, T.; López-López, J. M.; Odriozola, G.; Bastos-González, D.; Ortega-Vinuesa, J. L., Soft
Matter,2010, 6, 1114.
[5] Schiwerz, N., Horinek, D., Netz, R. R., Langmuir, 2013, 29, 2602
[6] Peula-García, J. M.; Ortega-Vinuesa, J.L.; Bastos-González, D., J. Phys. Chem. C. 2010, 114, 11133.
[7] Calero, C.; Faraudo, J.; Bastos-González, D., J. Am. Chem. Soc. 2011, 133, 15025.
[8] López-León, T.; Elaïssari, A.; Ortega-Vinuesa, J. L.; Bastos-González, D., ChemPhysChem. 2007, 8,
148.
[9] Pérez-Fuentes, L..; Drummond, C.;Bastos-González, D. Ion Specificity on pNIPAM microgels: An
AFM study. Under preparation.
INVITED LECTURES
52
I6
Electron dynamics in nanostructured metal-oxide films: novel routes towards
clean energy technologies
Juan A. Anta*
Department of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide,
41013 Sevilla, Spain
*
[email protected]
Nanostructured films of metal-oxide semiconductors are the focus of intensive
research nowadays due to their applications in the current quest for new sources of clean
energy. Metal-oxides like TiO2 and ZnO can be used to make efficient photoanodes for
photoelectrochemical solar cells and nanostructured substrates for photocatalytic production
of non-polluting fuels. ZnO, the first oxide utilized to make dye-sensitized solar cells, exhibits
an unique combination of potentially interesting properties such as high bulk electron mobility
and probably the richest variety of nanostructures based on a very wide range of synthesis
routes. In these applications electron transport through the nanostructure is crucial to achieve a
good photon-to-electron quantum efficiency. In this talk the current knowledge of the electron
transport mechanisms that take place in these systems is reviewed, highlighting the influence
of energy and morphological disorder on the efficacy of the transport process. A special
connection is made between the specificity of the electron transport in these systems and their
applications in solar cells and photocatalytic devices.
INVITED LECTURES
53
I7
Nanostructured surfaces of conducting polymers and applications in organic
photovoltaic cells
Ana Charas*
Instituto de Telecomunicações, Instituto Superior Técnico, Lisbon, P-1049-001, Portugal,
*
[email protected]
Organic photovoltaic cells (OPVs) using conjugated polymers as active components
represent a potential low-cost alternative to silicon-based solar cells, due to involving lower
manufacturing costs which are related to the capability of depositing the organic (active) layer from
liquid solutions, through printing technologies. Moreover, due to the structural properties of the
utilized polymers, lighter, semitransparent, and even flexible devices may be fabricated. This
allows conceiving new and appealing commercial applications, as vertical or curved powergenerating windows. However, OPVs still suffer from low values of energy conversion efficiency
and poor device stability. Both the chemical structure of the organic materials and the morphology
of the organic layer play a crucial role in the performance of such devices. Most efficient systems
are based on a nanostructured interpenetrating network comprising a conjugated polymer, acting as
an electron donor, and a fullerene derivative as an electron-accepting component. In this
communication, it is presented an approach to tailor the morphology of the organic layer, while
enhancing its stability, through the use of cross-linkable conjugated polymers [1-3]. We have
synthesized several new photo-active cross-linkable polymers, either poly(9,9-dialkylfluorene)s or
poly(3-alkyl-thiophene)s derivatives, whose cross-linking ability derives from oxetane moieties as
end-groups in the polymer side-chains (Figure 1) [1-3]. Oxetane moieties react through cationic
ring-opening polymerization leading to an insoluble polymer network. Our approach to reach
nanostructured layers of such polymers takes
advantage from the phase separation that occurs
during the polymer deposition when blended
with polystyrene standards, in solution, by the
spin coating technique. The resultant
morphologies are controlled by the blend
characteristics and the spinning speed of the
deposition. Using this approach, we have
tailored film morphologies aiming at enhancing
photocurrent generation and device stability.
Here, an overview of such research work is
presented.
Figure caption: Scheme of an organic photovoltaic cell comprising a nanostructured layer of a crosslinked conjugated polymer, as the electron donor, and a soluble fullerene (as the electron acceptor).
Acknowledgements: This work was financed by national funds through FCT – Fundação para a Ciência
e a Tecnologia (Portugal) under the projects «PTDC/CTM/111263/2009» and «PTDC/CTMNAN/1471/2012».
[1] Charas, A.; Ferreira, Q.; Farinhas, J.; Matos, M.; Fonseca, S.; Burrows, H.; Alcácer, L.; Morgado, J.,
Macromolecules 2009, 42, 7903-7912.
[2] Farinhas, J.; Ferreira, Q.; Di Paolo, R. E.; Alcácer, L.; Morgado, J.; Charas, A.; J. Mater. Chem.,
2011, 21, 12511-12519.
[3] Brotas, G.; Farinhas, J.; Ferreira, Q.; Morgado, J.; Charas, A., Synthetic Metals, 2012, 162, 20522058.
INVITED LECTURES
54
I8
Functional Hairy Particles and Films via Block Copolymer-Stabilized Emulsion
Polymerization
Hans Heuts1,*, Martin Fijten1, Alexandra Muñoz Bonilla2 and Alex van Herk3
1
Laboratory of Polymer Materials, Eindhoven University of Technology, The Netherlands.
2
Instituto de Ciencia y Tecnología de Polímeros, CSIC, Madrid, Spain.
3
Polymer Group, Institute of Chemical and Engineering Sciences, Singapore.
*
[email protected]
Polymer nanoparticles with functional groups on their outside are receiving an
increasing research interest, especially for their potential use in biomedical applications.
Instead of "clicking" functional chains onto the particle surface, a commonly used technique at
present, we have chosen an ab initio approach in which we already introduce the functional
groups at the beginning of the particle synthesis. We do this by using block copolymer
surfactants as stabilizers in emulsion polymerization and so produce functional hairy particles.
With the desired functionality present in the hydrophilic block, it will end up in the outer shell,
i.e., the "hairy layer", of the particles.
Using this approach, it should also be possible to control the number of "hairs" per
particle, as (depending on the respective block lengths) the block copolymer micelles can act
as a polymer seed for emulsion polymerization, resulting in a one-to-one conversion of
micelles into particles.[1] If, additionally, the aggregation number of block copolymers in the
micelles is known (and controllable via scaling laws), then the number of blocks per particle is
known. Finally, if the block copolymers show sufficient mobility during film formation of the
functional latex, it should be possible to create functional surface coatings. This process,
which we intend to control completely is schematically shown in Scheme 1.
It is clear that the nature of the hydrophilic block will determine the surface
properties of the functional polymer films. In the current presentation we will focus on the
results we obtained using four different block copolymer surfactants: one with a cationic
hydrophilic block, one with a glycopolymer block,[2] one with the hydrophilic block
containing PEG-brushes [3,4] and finally one that consists of two poly(oxazoline) blocks.
Scheme 1.
[1] Burgière, C.; Chassenieux, C.; Charleux, B., Polymer 2003, 44, 509–518.
[2] Muñoz-Bonilla, A.; Heuts, J. P. A.; Fernández-García, M., Soft Matter 2011, 7, 2493-2499.
[3] Muñoz-Bonilla, A.; Van Herk, A. M.; Heuts, J. P. A., Macromolecules 2010, 43, 2721-2731.
[4] Muñoz-Bonilla, A.; Ali, S. I.; Del Campo, A.; Fernández-García, M.; Van Herk, A. M.; Heuts, J. P.
A., Macromolecules 2011, 44, 4282-4290.
INVITED LECTURES
55
I9
Nanosized particles: Beyond a simple tool to fight against disease
Pablo Taboada*
Grupo de Física de Coloides y Polímeros, Facultad de Física, Universidad de Santiago de Compostela,
Campus Vida 15782, Santiago de Compostela, Spain
*
[email protected]
Since last decade a exponential interest in the study of the properties of inorganic and
organic nanosized structures has emerged for their intended use in biomedical applications.
Nanosized particles display properties that are mainly determined not only by their size,
morphology and composition, but also by the surrounding physico-chemical environment
where they are immersed. Their size is rather similar to that of many biomolecules present in
biological fluids such as proteins, hormones, lipids, sugars or of cellular substructures,
amongst others. This similarity facilitates their mutual interactions, enabling the
monitorization, induction, modification and/or manipulation of biological states. In fact, the
ability of nanotechnology to shape matter and its composition on the scale of molecules and
supramolecular aggregates open the door to achieve a full knowledge and a controlled
regulation of many different biological processes, which can be directly applied to the
development of a new generation of diagnostic imaging agents and therapeutic compounds for
detecting and treating diseases and, in particular, cancer. But perhaps more important, the
combined use of the tools provided by nanotechology together with clever combinations of
different nanomaterials are allowing researchers to create new external/internal-stimuli
responsive nanosized platforms that may contain drug compounds designed to kill tumours on
demand, with targeting ligands designed to only interact with malignancies, and imaging
contrast agents designed to light up even the earliest stage of cancers, all this giving rise to a
new field known as theranostics (therapy + diagnostics). Also, a description of cancers in
molecular terms are likely to improve the way in which malignancy are detected, identified,
monitored, and treated and for that, nanosized particles, which allow to address molecular
structure thanks to their nanometer-size, may be specially useful. However, it is necessary to
bear in mind that there are still some controversial points which need a deeper understanding
before a definitive clinical application can take place, as the elimination of any concern about
potential partcile nanotoxicity, or the achievement of a full knowledge of the mechanisms
underlying particle-biomolecules and particle-cell mutual interactions.
In this talk, several examples about the role played by nanosized particles in the
induction/modification of cellular and/or biomolecular responses and how different
configurations of these kind of nanomaterials can lead to the construction of really effective
multifunctional theranostic nanodevices able to possses simultaneous capabilities of both
multi-imaging diagnostics and multi-therapeutics to fight gainst cancer will be presented. A
special emphasis will be devoted to the work my research group is developing in this field.
INVITED LECTURES
56
I10
Towards an integrated plasmonic platform
for early cancer detection
R. Quidant1,2,*
1
ICFO-Institut de Ciencies Photoniques, Mediterranean technology Park, Castelldefels (Barcelona),
Spain
2
ICREA-Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, Barcelona, Spain
*[email protected]
Nanoscale control of plasmonic fields in engineered metal nanostructures offers
unique opportunities to boost the interaction of light with tiny amount of matter, down to the
single molecule level. In particular, such enhanced interaction can strongly benefit to the
detection of small amounts of molecules, such as proteins for diagnosis purposes.
In the present paper we present recent advances obtained within the framework of
SPEDOC [1], European initiative that aims at combining the latest advances of
nanoplasmonics, microfluidics and oncology to develop an integrated platform for early
cancer detection and treatment monitoring. In particular, we will discuss different plasmonbased strategies developed within SPEDOC for the detection of low concentration of cancer
markers in blood.
[1] www.spedoc.eu
CLOSING TALKS
CLOSING TALKS
59
CT1
Synthesis of Nano-coral like colloidal particles via water-in-oil miniemulsion
R. Ladj1,2, Y. Mounier2, R. Le-Dantec2, H. Fessi1 and A. Elaissari1,*
1
University of Lyon, F- 69622, Lyon, France; University of Lyon-1, Villeurbanne, CNRS,
UMR 5007, LAGEP-CPE-308G, 43 bd. du 11 Nov.1918, F-69622, Villeurbanne, France.
2
Université de Savoie, Laboratoire SYMME, BP 80439, 74944 Annecy le Vieux Cedex, France.
*
[email protected]
Hybrid nanoparticles are one of the most important classes of colloidal materials due to
the current interest in biomedical field, supported chemistry and physical area. These hybrid
materials bearing intrinsic physical properties can be used in-vitro biomedical imaging. Iron iodate
nanocrystals having a noncentrosymmetric structure can be used as nonresonant nonlinear optical
probes for bioimaging applications in vitro by use of the second order processes of second
harmonic. These nonresonant processes provide advantages above and beyond traditional two
photon bioimaging: (i) no photobleaching effect; (ii) coherent and stable signals with good
flexibility in the choice of excitation wavelength; and (iii) no heat dissipation into the cells,
ensuring longer cell viability and ultimately longer imaging times. Then, the aims of this work if to
prepare iron iodate nanocrystals for in vitro biomedical imaging. To target such object, submicron
nanoparticles should be prepared and then encapsulated in order to induce biocompatibility (i.e.
non cytotoxicity effect).
Iron iodate colloid nanoparticles have been prepared through mixing two water-in-oil
miniemulsions of iron nitrate and iodic acid salt to obtain water-in-oil miniemulsion of iron iodate.
The nanocrystals were obtained via precipitation reaction of IO3- and Fe3+ ions inside aqueous
nanodroplets (i.e. nanoreactors). The water-droplet emulsions were prepared using span 80 as
surfactant below CMC in cyclohexane (as continuous phase). The fragmentation was performed
using ultrasound emulsification. The physicochemical properties of the water droplets containing
iron iodate nanoparticles are characterized by TEM and SEM to examine the morphology of
particles, DRX analysis to study the noncentrosymmetric crystalline structure, dynamic light
scattering for particle size analysis, potential zeta for surface properties and infrared analysis. In
addition, the cytotoxicity and second-harmonic imaging of nanoparticles were investigated via invitro study.
natural coral
nanocorale like particles
Acknowledgements: This research has been partially conducted under the European FP7 Research Project
NAMDIATREAM (NMP4-LA-2010-246479, http://www.namdiatream.eu) and INTERREG IV France-Switzerland
NAOMI
CLOSING TALKS
60
CT2
Hydrophobic Interactions Modulate Self-assembly of Gold Nanoparticles
Marek Grzelczak 1,2,*, Ana Sánchez-Iglesias 1, Thomas Altantzi 3, Bart Goris 3, Jorge PerezJuste 4, Sara Bals 3 , Gustaaf Van Tendeloo 3, Stephen H. Donaldson Jr.5, Bradley F.
Chmelka5, Jacob N. Israelachvili 5, and Luis M. Liz-Marzán 1,2,4,*
1
CIC biomaGUNE, Spain; 2Ikerbasque, Basque Foundation for Science, Spain;.
University of Antwerp, Belgium; 4Universidade de Vigo, Spain; 5University of California, USA
*
[email protected], *[email protected]
3
Hydrophobic interactions constitute one of the most important types of non-specific
interactions in biological systems, which emerge when water molecules rearrange as two
hydrophobic species come close to each other. Prediction of hydrophobic interactions at the
level of nanoparticles (Brownian objects) remains challenging, because of uncontrolled
diffusive motion of the particles. We show that polystyrene (PS)-stabilized spherical gold
nanoparticles dispersed in tetrahydrofuran (THF) can form monodisersed aggregates upon
addition of water, which is a bad solvent for PS (Scheme 1).[1] The growth of the clusters can
be quenched by addition of a polymeric surfactant comprising hydrophobic (polystyrene) and
hydrophilic (poly-acrylic acid) blocks (PS-b-PAA). While micellization of the polymeric
surfactant allows for sequestration of clusters inside the hydrophobic core, the hydrophilic
outer surface of the micelles (comprising the PAA blocks) ensures stability in polar solvents.
Figure caption: Three-dimensional self-assembly of polystyrene-coated gold nanoparticles. Dispersion of
polystyrene-coated gold nanoparticles in THF undergoes aggregation in the presence of water. The
addition of polymeric surfactant (PS-b-PAA) suppresses further aggregation of the nanoparticles,
producing stable clusters.
[1] Sánchez-Iglesias, A.; Grzelczak, M.; Altantzis, T.; Goris, B.; Pérez-Juste, J.; Bals, S.; Van Tendeloo,
G.; Donaldson, S. H.; Chmelka, B. F.; Israelachvili, J. N.; Liz-Marzán, L. M., ACS Nano 2012, 6,
11059–11065.
CLOSING TALKS
61
CT3
Phase diagram of Magnetic filaments in bulk and near surfaces
Joan J. Cerdà1,*, Pedro A. Sánchez2, C. Holm2 and Tomàs Sintes1
1
Instituto de Física Interdisiciplinar y Sistemas Complejos - IFISC (CSIC-UIB), Majorca, Spain.
2
Institute for Computational Physics- ICP (Universtität Stuttgart), Stuttgart, Germany
*
[email protected]
Artificial magnetic filaments can be obtained by mutually linking magnetic colloids to
form a chain. These magnetic chains represent the equivalent to magnetic polymers but at supramolecular scale. In difference to one-dimensional chemical magnetic polymers which only
manifest their magnetic properties at T<100K, magnetic filaments can retain their magnetism at
room temperature and zero field.
In this contribution we present the results of our previous studies [1, 2, 3] on the
equilibrium conformations of flexible and semiflexible magnetic filaments in different physical
environments of relevance for forthcoming applications. In particular, we focus on the
determination of the phase diagram at zero field for magnetic filaments which monomers exhibit
short-range LJ attractive interactions (Stockmayer polymers, i.e. filaments in poor solvent
conditions) in the limit of strong dilution, as well as filaments in good solvent conditions. We
study the cases of magnetic chains in bulk (see figure 1) and near an attractive surface. We find
that the phase diagrams of magnetic systems exhibit a rich variety of new phases when compared
with non-magnetic chains in similar environments.
The emerging interest in this relatively novel field is due to the fact that magnetic
filaments are very appealing from the technological point of view. They can be thought as
improved substitutes of current ferrofluids, or as elements for magnetic memories, chemical and
pressure nanosensors, micro-propellers, non-permanent photonic crystals, and generation of
unique patterns able to provide watermarks to authenticate cards or other documents, to just
mention a few.
Figure caption: A tentative phase diagram for magnetic filaments of length N=100, and a dipole moment per
monomer of fixed strength μ²=5.
Acknowledgements: We thank the projects FISICOS (FIS2007-60327), GRID-CSIC and BwGrid founded by
the Spanish MICNN and the ERDF, respectively.
[1] Sánchez, P. A.; Cerdà, J. J.; Ballenegger, V.; Sintes, T.; Holm, C. Soft Matter, 2011, 7, 1809
[2] Cerdà, J. J.; Sánchez, P. A.; Holm, C.; Sintes, T. submitted to Soft Matter, arXiv:1302.5897.
[3] Sánchez, P. A.; Cerdà, J. J.; Sintes, T.; Holm, C. submitted to JCP, arXiv:1302.5845
CLOSING TALKS
62
CT4
Wetting-induced fluid entrainment and drop emission for driven fluid filaments
I. Pagonabarraga*
Departament de Física Fonamental, Universitat de Barcelona,
Carrer Martí i Franqués 1, 08028-Barcelona, Spain
*[email protected]
Forced liquid films or filaments detach from the solid they displace on when the
contact line cannot follow the motion of the rest of the film under the action of a driving force.
The instability onset is sensitive to the equilibrium contact line and different patterns can be
promoted by tuning the chemical composition of an heterogeneous solid substrate[1]. I will
discuss in this presentation the interplay between equilibrium and dynamic wetting to control
the stability of an advancing liquid front. I will describe a theoretical analysis to understand
the relevance of the friction at the contact line[2]. For liquid mixtures with large interfacial
widths (as is the case for colloid/polymer mixtures) this local friction plays a relevant role in
the onset of entrainment of forced thin films. I will also present results of numerical
simulations to analyze the onset of entraiment and analyze the drops that are emitted[3]. This
study indicates that equilibrium wetting properties of a substrate can be used as an alternative
mechanism to emit small drops. The theoretical predictions and the numerical evidence
explain experimental results of entrainment in superhydrophobic surfaces and in the
instabilities observed on the dynamics of colloid/polymer mixtures in Hele-Shaw cells.
Figure caption: Liquid filaments forced on chemical stripes of prescribed equilibrium contact angle, at
varying capillary numbers. Above a characteristic Ca, which depends on the equilibrium contact angle,
drops are emitted.
[1] Ledesma-Aguilar R.; Hernández-Machado, A.; Pagonabarraga, I., Soft Matter, 2011, 7, 6051
[2] Ledesma-Aguilar R.; Hernández-Machado, A.; Pagonabarraga, I., submitted
[3] Ledesma-Aguilar R.; Nistal, R.; Hernández-Machado, A.; Pagonabarraga, I., Nature Mater., 2011,
10, 367
CLOSING TALKS
63
CT5
Non-NIPAM based microgels: Tuning the volume phase transition by
copolymerisation and by particle architecture
Thomas Hellweg1,*, Michael Zeiser1 and Bastian Wedel1
1
Universität Bielefeld, Fakultät für Chemie Physikaische und Biophysikalische Chemie,
Universitätsstr. 25, 33615 Bielefeld, Germany.
*
[email protected]
Most of the so-called smart microgels studied in the last 20 years were mainly based
on poly(N-isopropylacrylamide (PNIPAM). Only a few works used alternative acrylamides
like e.g. poly(N-isopropylmethacrylamide) (PNIPMAM) [1].
In our recent work we have shown that especially the use of alternatives to PNIPAM
leads to very interesting new properties of the obtained materials [2,3]. An example for the
swelling behaviour of the new materials is given in the left part of the figure below, which
shows the hydrodynamic radius of core-shell microgels with a shell made of N-npropylacryalmide and a core of PNIPMAM. These two polymers have a difference in the
lower critical solution temperature of about 21 °C. This difference leads to the new swelling
properties.
Also statistical copolymers of the same monomers were studied. His approach can be
used to continuously tune the phase transition temperature of the obtained materials.
The talk will review these works.
Figure caption: (left) Swelling curve of a PNNPAM-PNIPMAM core-shell system with a core
containing 12.5 mol% crosslinker; (right) SEM image of the same particles.
[1] Berndt I.; Richtering W., Macromolecules, 2003, 36, 8780.
[2] Wedel B.; Zeiser M.; Hellweg T., Z. Phys Chem, 2012, 226, 737
[3] Zeiser, M.; Freudensprung, I.; Hellweg, T., Polymer, 2012, 53, 6096
CLOSING TALKS
64
CT6
Plasmonic Nanoparticles based on Colloid Chemistry
A. Guerrero-Martínez1,* and L. M. Liz-Marzán2
1
Departamento de Química Física I, Universidad Complutense, Avda. 20 Complutense s/n, 28040,
Madrid, Spain
2
BioNanoPlasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia - San
Sebastián, Spain
*
[email protected]
Nanoplasmonics can be defined as the science that studies the excitation of surface
plasmon resonances on metal nanostructures, and their potential technological applications
[1]. Such localized surface plasmons arise from the interaction between light and the
conduction electrons in nanostructured metals, yielding bright colors in disperse metal
nanoparticles. These colors can be tuned by changing different parameters such as the size,
shape, and composition of the particles, but also the dielectric nature of the surroundings [2].
In the case of anisotropic particles, the optical response directly depends on the polarization of
the incident light, which allows an additional degree of manipulation [3]. Moreover, these
localized surface plasmons give rise to high electric fields at the metallic surface, which can
be controlled and amplified from colloidal self-assembly [4]. All these effects open new
perspectives for designing new devices with applications in a wide variety of fields.
Acknowledgements: This work has been funded by the European Research Council (ERC Advanced
Grant #267867 Plasmaquo). A.G.-M. acknowledges receipt of a Ramón y Cajal Fellowship from the
Ministerio de Economía y Competitivdad.
[1] Guerrero-Martínez, A.; Grzelczak, M.; Liz-Marzán, L. M. ACS Nano 2012, 6, 3655.
[2] Jain, P. K.; Lee, K. S.; El-Sayed, I. H.; El-Sayed, M. A. J. Phys. Chem. B 2006, 110, 7238.
[3] Guerrero-Martínez, A.; Augié, B.; Alonso-Gómez, J. L.; Džoli, Z.; Gómez-Graña, S.; Žini, M.;
Cid, M. M.; Liz-Marzán, L. M. Angew. Chem. Int. Ed. 2011, 50, 5499.
[4] Guerrero-Martínez, A.; Pérez-Juste, J.; Carbó-Argibay, E.; Tardajos, G.; Liz-Marzan, L. M. Angew.
Chem. Int. Ed. 2009, 48, 9484.
CLOSING TALKS
65
CT7
A chemical garden model for the formation mechanism of brinicles
Bruno Escribano1,*
1
Basque Center for Applied Mathematics, Bilbao, Spain.
*
[email protected]
Chemical gardens are a common and well known experiment where hollow tubes
grow from a metal salt crystal immersed in a solution of silicate or other anions. The
formation process is a combination of filtering and precipitation: a metal-silicate
semipermeable membrane coats the crystal and intakes water by filtering it from the silicate
solution; the tubes grow by precipitation around a flow of metal solution ejected when the
membrane bursts. On the other hand, brinicles are hollow tubes of ice that form when dense,
cold brine drains downward from polar ice sheets into sea water at its freeing point. In this
case the ice sheet supplies the filtering mechanism by crystallizing water molecules and
accumulating concentrated brine in trapped compartments within the ice, a process known as
brine rejection. Precipitation occurs when this cold brine is ejected from the ice and comes
into contact with the sea water, freezing it around the brine flow and forming a tubular
structure.
Brinicles are difficult to study because they only grow under polar ice sheets during
winter and in calm waters. For this reason their formation mechanism is still not completely
understood. However, their possible role in the theories for a cold origin of life [1,2] has
attracted recent attention. Here, we use our experience working with chemical gardens [3] and
apply it to better understand the formation mechanism of brinicles [4]. In this way we intend
to answer some of the open questions regarding brinicle formation, such as: What is the
trigger mechanism? How does the brine flow remain constant? How does brine migrate within
the ice?
Figure caption: Schematic representation of the brinicle formation process.
[1] Trinks, H.; Schröder, W.; Bierbricher, C. K. Origins Life Evol. Biospheres 2005, 35, 429–445.
[2] Bartels-Rausch, T. et al. Rev. Mod. Phys. 2012, 84, 885–944.
[3] Cartwright, J. H. E.; Escribano, B.; Sainz-Díaz, C. I.; Stodieck, L. S. Langmuir 2011, 27,
3294–3300.
[4] Cartwright, J. H. E.; Escribano, B.; González, D. L.; Sainz-Díaz, C. I.; Tuval, I. Langmuir 2013,
DOI: 10.1021/la40097
ORAL COMMUNICATIONS
NANOPARTICLES: ORGANIC, INORGANIC AND HYBRIDS
69
O1.1
Light-Addressable and Degradable Silica Capsules for Cytosolic Release
S. Carregal-Romero1,2,*, A. Ott,1 and W. J. Parak1
1
Biophotonics department, Institute of Physics and WZMW, Philipps-Universität Marburg, Renthof 7,
35037 Marburg, Germany.
2
Andalusian Center for Nanomedicine and Biotechnology (BIONAND), Andalusian Technological Park.
C/ Severo Ochoa, 35, 29590 Campanillas, Málaga, Spain.
*
[email protected]
Plasmonic nanoparticles can be used to destroy cancer cells and tumors by applying
light. Cancer cells are more sensitive to slight increases of temperature and therefore the
relaxation of the electrons that had absorbed light into heat can be used to produce
hyperthermia and tumor destruction.[1,2] Applying lower power density of light, similar
plasmonic structures can optically trigger the delivery of certain drugs and biofunctional
molecules from their surface or from microscopic structures acting as carrier systems.[3,4]
Light-responsive polyelectrolyte capsules have been used as efficient carrier systems to
deliver into the cytosol different kinds of proteins and molecules such mRNA by keeping
intact their biological activity.[4] In this work, we describe the synthesis of silica capsules that
depending on the composition can deliver functional molecules through degradation or lighttriggered release. The two different release mechanisms of cargo molecules in vitro will be
discussed and compared with the aforementioned polyelectrolyte capsules.
Figure caption: Cytosolic release of pH sensor dye from a silica capsule.
[1] Qin, Z.; Bischof, J. C. Chem. Soc. Rev. 2011.
[2] O'Neal, D. P.; Hirsch, L. R.; Halas, N. J.; Payne, J. D.; West, J. L. Cancer Letters 2004, 209, 171.
[3] Huschka, R.; Barhoumi, A.; Liu, Q.; Roth, J. A.; Ji, L.; Halas, N. J. ACS Nano 2012, 6, 7681.
[4] Ochs, M.; Carregal-Romero, S.; Rejman, J.; Braeckmans, K.; De Smedt, S. C.; Parak, W. J. Angew.
Chem., Int. Ed. 2013, 52, 695.
70
O1.2
Silicon Colloids with a strong magnetic response below 1.5 micrometers region
Lei Shi1,2, Roberto Fenollosa1,2*, Francisco Meseguer1,2
1
Consejo Superior de Investigaciones Científicas (Unidad Asociada Instituto de Ciencia de Materiales
de Madrid (CSIC) – Universidad Politécnica de Valencia)
2
Centro de Tecnologías Físicas, Edificio 8B Bloque K, Universidad Politécnica de Valencia,
Avda. Tarongers s/n, Valencia, Spain
*
[email protected]
It is generally accepted that the magnetic response of materials at optical frequency
values is completely negligible. The recent discovery of Metamaterials (MMs) has broken this
traditional understanding, since both the electric and the magnetic field are key ingredients in
MMs [1]. Although, MMs have shown their potential for molding light matter interaction,
unsolved problems remain that prevent their use in practical applications. One challenge
concerns the intrinsic losses in the optical range of noble metals used for MMs processing [2].
One potential way to circumvent this obstacle concerns using high refractive index value
dielectric structures, which may show strong magnetic and electric resonances [3].
Particularly, Mie resonances of high refractive index optical nanocavities may open a new
route to realize low loss isotropic metamaterials. Here we report on the synthesis and the
optical properties of silicon colloids based nanocavities with strong magnetic response in the
NIR region [4,5]. The transmission and reflection properties of single silicon colloids with
size values between 250 nm and 700 nm are reported. Both, experiments and theoretical
calculations (Mie theory and the finite difference time domain (FDTD) simulations) clearly
show that single submicron silicon nanocavities support well defined magnetic resonances in
NIR region at wavelength values up to six times larger than the cavity radius.
[1] Soukoulis, C. M.; Wegener, M., Nat. Photon., 2011, 5, 523.
[2] Zheludev, N.I., Science, 2010, 328, 582.
[3] Popa, B.; Cummer, S. A., Phys. Rev. Lett., 2008, 100, 207401.
[4] Shi, L.; Tuzer, T. U.; Fenollosa, R.; Meseguer, F., Adv. Mater., 2012, 24, 5934.
[5] Shi, L.; Harris, J.; Fenollosa, R.; Rodriguez, I.; Lu, X.; Korgel, B. A.; Meseguer, F. (submitted)
71
O1.3
Resizing of colloidal gold nanorods using aqueous K2S2O8 and morphological
probing by SERS
Sara Fateixa1,*, Tito Trindade1
1
Department of Chemistry-CICECO, Aveiro Institute of Nanotechnology,
University of Aveiro, Portugal
*
[email protected]
Surface Enhanced Raman Scattering (SERS) is a vibrational spectroscopic technique
that provides valuable information about the nature and orientation of molecular species
adsorbed at metal surfaces and on the adsorbate–metal interaction mechanism >1, 2@. On the
other hand, the morphological characteristics of metal nanoparticles used as SERS substrates
have strong influence on the Raman signal >3, 4@. In this report we present the use of SERS as
a method to monitor the resizing of colloidal AuNRs treated with aqueous K2S2O8, at room
temperature.
Hence, these SERS studies have been performed using colloidal Au nanorods (NRs)
collected at different stages of oxidation, using diluted sodium diethyldithiocarbamate as
molecular probe, and using the NIR excitation line (1064 nm). The results showed that the
SERS sensitivity of the Au NRs substrates decreased with the decrease of the particle A.R., as
estimated on the basis of analytical enhancement factors. We will discuss this approach as an
alternative to probe in situ morphological changes on Au NRs that are routinely performed by
measuring the respective VIS/NIR spectra and whose characteristics are well known to vary
with particle shape and size.
Figure caption: Digital photographs of colloidal Au NRs submitted to aqueous K2S2O8, at variable
reaction times.
Acknowledgements: S. Fateixa thanks Fundação para a Ciência e Tecnologia (FCT/FEDER) for the
grant SFRH/BD/66460/2009. The authors thank FCT (PTDC/CTM-NAN/120668/2010; PestC/CTM/LA0011/2011), FSE and POPH for funding.
[1] Kneipp, J.; Kneipp, H.; Kneipp, K., Chem. Soc. Rev. 2008, 37, 1052–1060.
[2] Sharma, B.; Frontiera, R. R.; Henry, A.; Ringe, E.; Van Duyne, R. P., Materials Today 2012, 15, 1625.
[3] Orendorff, C. J.; Gole, A.; Sau, T. K.; Murphy, C. J., Anal. Chem. 2005, 77, 3261-3266.
[4] Link, S.; Mohamed, M. B.; El-Sayed, M. A., J. Phys. Chem. B 1999, 103, 3073-3077.
72
O1.4
Organized plasmonic clusters with high coordination number and extraordinary
SERS enhancement
Nicolas Pazos-Perez1,*, Claudia Simone Wagner2, Luis M. Liz- Marzan3, F. Javier Garcia de
abajo4, Alexander Wittemann2, Ramon Alvarez-Puebla5 and Andreas Fey1
1
Department of Physical Chemistry II, University of Bayreuth, 95440, Bayreuth, Germany.
2
Colloid chemistry, University of Konstanz, 78464 Konstanz, Germany
3
Department of Physical Chemistry, University of Vigo, 36310, Vigo, Spain
4
Instituto de Quimica-Fisica Rocasolano-CSIC, 28006, Madrid, Spain
5
ICREA - Catalan Institution for Research and Advanced Studies, Spain
*
[email protected]
Noble metal nanoparticles exhibit optical excitations known as surface plasmons.
Plasmonic nanoparticles are in the focus of attention because of their interesting electric and
optical properties. These types of materials produce a large enhancement of the local light
intensity under external illumination. Plasmons are highly related to the specific particle size
and shape. There are various synthetic procedures which allow us to fine tune these
parameters in order to adjust their plasmonic response. However, the enhancement of the local
light increases particularly when particles are arranged in closely spaced configurations. This
is due to the formation of hotspots with high electromagnetic fields. Thus, a critical role in the
hot spot generation is the inter-particle gap distance.
Controlled assembly using colloidal chemistry is an emerging and promising field for
high yield production of metal nanoparticle clusters with small inter-particle gaps. However,
most of the reported methods rely on the use of nucleic acids or other organic molecules as
linking elements, which yield long separation distances and thus small plasmon coupling.
Additionally, only simple clusters such as dimmers and trimmers have been efficiently
synthesized. In this work, we report the controlled assembly of gold nanospheres into welldefined nanoparticle clusters with large coordination numbers (up to 7) and high symmetry.
We further demonstrate ultrasensitive direct and indirect surface-enhanced Raman scattering
(SERS) sensing, thus corroborating the outstanding optical performance of these clusters with
robust enhancement factors over 3 orders of magnitude higher than those of single particles.
Figure caption: a) Density gradient separation to
obtain a specific population from the initial
mixture of clusters. b) SEM micrographs of the
different cluster populations obtained after
careful fractionation of the corresponding
stripes in image (a). c) Representative HR-TEM
images of particle dimers and trimers illustrating
the small interparticle gaps and cavities
generated by this fabrication method.
[1] Pazos-Perez, N., et al., Angew. Chem. Int. Ed., DOI: 10.1002/anie.20120701.
73
O1.5
Efficient eco-friendly dye nano-adsorbents based on biopolymer surface
functionalized magnetic nanoparticles
Ana L. Daniel-da-Silva*, Ana M. Salgueiro, Bianca Creaney and Tito Trindade
CICECO, Chemistry Department, Aveiro Institute of Nanotechnology, University of Aveiro,
3810-193 Aveiro, Portugal
*
[email protected]
Organic dyes are present in the effluents of a number of industries (e.g. textile, paper,
plastic) and their discharge in water supplies is a matter of concern due their harmful impact
on the environment and potential mutagenic and carcinogenic effects. Although a number of
materials have been explored as dye adsorbents, the need of more environmentally friendly
and low-cost dye adsorbents has raised the attention to biopolymers obtained from renewable
resources, such as polysaccharides. [1] This work aims the development of effective dye
adsorbents easily separated, based on biopolymer surface modified magnetic nanoparticles.
Magnetite (Fe3O4) nanoparticles (NPs) were synthesized using the co-precipitation method.
The surface of the magnetic NPs was then modified using N-, L- and O-carrageenan, a family
of sulfated polysaccharide extracted from red algae, using two different chemical strategies:
the physical immobilization of carrageenan macromolecules onto the surface and the covalent
linkage of carrageenan chemically modified with carboxymethyl groups. The composite NPs
were tested as adsorbents for the magnetically assisted removal of methylene blue (MB) from
aqueous solutions in batch experiments.
Under the experimental conditions used, MB could be recovered fast (< 1 hour) and
efficiently, due to electrostatic interaction with the sulphate moieties of carrageenan. Kinetic
and equilibrium adsorption studies were carried out. The MB adsorption onto coated NPs has
shown an unusual Z-type isotherm which suggests the generation of new adsorbing sites with
increasing MB initial concentration. The NPs with carrageenan covalently linked to the
surface could be well-regenerated after adsorption and reused at least for 5 cycles of
desorption-adsorption without significant decrease of the MB removal capability. These
materials displayed MB adsorption capacity higher than other magnetic sorbents previously
reported. Thus, carrageenan surface modified magnetite NPs are very promising eco-friendly
materials for removing MB from wastewater using magnetic separation.
Acknowledgements: FCT - Fundação para a Ciência e Tecnologia (PTDC/CTM-NAN/120668/2010,
Pest-C/CTM/LA0011/2011, SFRH/BPD/66407/2009, FSE and POPH for funding. We thank the RNME
(National Electronic Microscopy Network) for TEM facility and to Dr. G. Goya (INA, Zaragoza, Spain)
for magnetic measurements.
[1] Crini G., Prog. Polym. Sci. 2005, 30, 38-70.
74
O1.6
Microfluidic Self-Assembly of Polymeric Nanoparticles in Aqueous Solutions
and Controlled Drug Delivery
Erfan Dashtimoghadam1, Hamid Mirzadeh1, Faramarz Afshar Taromi1, and Bo Nyström2,*
1
Department of Polymer Engineering and Color Technology, Amirkabir University of Technology,
Tehran, Iran.
2
Department of Chemistry, University of Oslo, Oslo, Norway.
*
[email protected]
An important challenge in the development of polymeric nanoparticles for various
applications is precise engineering of the desired physicochemical characteristics in a reproducible
manner. This presentation concerns the use of microfluidics to control the local polymer
concentration inside polymeric nanoparticles and to produce nanoparticles with a narrow size
distribution. A schematic illustration of the device is given in Fig. 1. It is demonstrated that the
compactness of nanoparticles based on self-assembled hydrophobically modified chitosan (HMCs)
can be dictated with tunable rapid mixing via hydrodynamic flow focused in microfluidic channels
[1,2]. It is shown by varying the flow rates, as well as the hydrophobicity of the chitosan
biopolymer that the self-assembly behavior of the chains can be controlled by optimizing the size
and compactness of the species, along with a more narrow size distribution of the nanoparticles.
The size of the particles increased with increasing mixing time, whereas smaller and more compact
nanoparticles, comprising of a less number of aggregated chains, are produced for chitosan of
higher degrees of hydrophobicity. It was realized that at higher degrees of hydrophobicity and at
mixing times longer than the time of aggregation, nanoparticles comprising of almost the same
number of hydrophobic stickers were formed.
Furthermore, we explored the effectiveness of microfluidic directed to assemble HMCs
and to encapsulate paclitaxel (PTX), a common anticancer drug, which revealed remarkably higher
encapsulation efficiency compared to the conventional bulk method. The in-vitro release of PTX
from the prepared nanoparticles was evaluated to investigate the effect of compactness of the
particles on the release profile. The estimated values of the diffusion coefficient of PTX up to 50%
release implied controlled sustainability of the drug release with respect to the compactness of the
nanoparticles,
and a remarkable
improvement compared to the uneven
bulk mixing method. These findings
indicate a high potential of the
microfluidic approach for precise
bottom-up controlling physicochemical
properties of polymeric nanoparticles for
various applications, such as controlled
drug delivery systems.
Figure caption: (a) Schematic illustration of the T-shaped microfluidic system used for synthesis of HMCsbased nanoparticles; the HMCs solution stream is hydrodynamically focused with lateral sheath flow of basic
water (pH=9). (b) Fluorescence image of Rhodamine B stream, which is hydrodynamically focused with
fluorescein sodium (scale bar 100 m). (c) AFM image of HMCs-3 nanoparticles synthesized at flow ratio of
0.031, showing a spherical structure (scale bar 200 nm).
[1] Demello, A. J. Nature 2006, 442, 394-402.
[2] Whitesides, G. M. Nature 2006, 442, 368-373.
75
O1.7
New applications modifying colloidal particles with ion-specific ligands
Dorleta Jimenez de Aberasturi1,2,*, Dominik Hühn1, Ricardo Pinedo2, Idoia Ruiz de
Larramendi2, Teofilo Rojo2, Jose Maria Montenegro Martos1, Susana Carregal1,
Wolfgang J. Parak1
1
Fachbereich Physik and WZMW, Philipps Universität Marburg, Marburg, Germany
2
Department of Inorganic Chemistry, UPV/EHU, Bilbao, Spain
*
[email protected]
Functionalized colloidal nanoparticles have distinctive properties that contribute to
promising applications. Moreover, they can introduce new properties to existing materials and
thus are a valuable building block for the construction of novel materials. In case we combine
ion-selective ligands with particles their functionality can be expanded significantly [1]. By
modifying the surface of colloidal particles with ion-specific ligands we can use them for
different applications such as sensing [2], imaging [3], and separation [4].
Ion-specific ligands can be directly integrated in the surface of colloidal
nanoparticles. Specific bindings of ions to those ligands can be translated in a change of
fluorescence when the particles or the ligands are fluorescent [5].or in an increased contrast
for imaging if the bound ions are ones such as Gd or In, useful as contrast agents[6]. Hence,
fluorescence-based ion sensors or particles as contrast agents can be constructed attaching ionspecific ligands to colloidal nanoparticles.
Alternatively polyelectrolyte capsules as a carrier for ion-specific ligands can also be
used, incorporating ion-selective ligands into the capsule cavities and walls. When the walls of
the capsules are modified with different nanoparticles, additional properties are provided to
the capsules [7-8]. Magnetic microparticles, that include magnetic nanoparticles in their walls,
can be used for magnetic separation purposes giving the possibility to extract and separate the
ions from solutions that bind to the ligands selectively [9-10].
In summary, due to the technique of combining ion-selective ligands with colloidal
particles, new fields of applications are provided for these molecules.
[1].Riedinger, A.; Zhang, F.; Dommershausen, F.; Röcker, C.; Brandholt, S.; Nienhaus, G. U.; Koert, U.;
Parak, W. J., Small 2010, 6, 2590-2597.
[2] Jimenez de Aberasturi, D.; Montenegro, J. M ; Ruiz de Larramendi, I.; Rojo, T.; Klar, T. A.; AlvarezPuebla, R.;. Liz-Marzán, L. M.; Parak, W. J., Chem Mater. 2012, 24,738-745
[3] Ali, Z.; Abbasi, A. Z.; Zhang, F.; Arosio, P.; Lascialfari, A.; Casula, M. F.; Wenk, A.; Kreyling, W.;
Plapper, R.; Seidel, M.; Niessner, R.; Knöll, J.; Seubert, A.; Parak, W. J., Anal. Chem. 2011, 83, 28772822.
[4] Manuel Perez. J.; Nature Nanotechnol., 2007, 2, 535 - 536
[5] Ruedas-Rama, M. J.; Orte, A.; Hall, E. A. H.; Alvarez-Pez, J. M.; Talavera, E. M. Chem. Commun. 2011,
47, 2898-2900.
[6] Carregal-Romero,S.; Caballero-Díaz, E.; Beqa, L.; Abdelmonem, A.M.; Ochs, M.; Hühn, D.; Suao, B.S.;
Valcarcel, M.; Parak W. J., Anal. Chem., 2013, 6 (in press)
[7] Abbasi, A. Z.; Gutiérrez, L.; del Mercato, L. L.; Herranz, F.; et al., J. Mater. Chem. C, 2011,115, 62576264.
[8] Ochs, M.; Carregal-Romero, S.; Rejman, J.; Braeckmans, K.; De Smedt, S.C.; Parak, W. J.; Angew. Chem.
Int. Ed. 2013, 52, 695 –699
[9] Colombo, M.; Carregal-Romero, S.; Casula, M. F.; Gutiérrez, L.; Morales, M. P.; Böhm, I. B.; Heverhagen,
J. T.; Prosperi, D.; Parak, W. J., Chem. Soc. Rev., 2012, 41 4306-4334.
[10] Uheida, A.; Iglesias, M., J. Colloid Interface Sci., 2006, 301,402–408
76
O1.8
Optimized Synthesis of Gold Nanorods
Leonardo Scarabelli1,*, Marek Grzeclzak1,2, Luis M. Liz-Marzán1,2
1
BioNanoPlasmonics Laboratory, CICBiomaGUNE.
Paseo Miramón 182, 20009 Donostia-San Sebastían, Spain
2
Ikerbasque, Basque Foundation for Science, 48011 Bilbao, Spain
*
[email protected]
Gold nanorods are one of the most studied metallic anisotropic nanoparticles. Their
optical/electronic properties and the possibility to create assemblies both in two and three
dimensions make them suitable candidates for a large number of applications, from sensing to
cancer therapy or catalysis. However, the production of a library of gold nanorods with
different length, thickness and size is still a challenge. This represents an obstacle for a
detailed study of the size-dependence of the properties involved in the production of devices
for scientific or technological applications. Recently, the use of co-factors to achieve better
tunability of the synthetic protocols has been reported [1]. In this work we present how using a
mild reducing agent (5-Bromo Salicylic Acid) it is possible to tune the final aspect ratio of
gold nanorods over a wide range and to perform overgrowth and super-overgrowth steps to
increase the size of the particles to a desired dimension. This allows us to produce a library of
colloidal solutions that can be exploited for a systematic study of the properties of gold
nanorods.
Acknowledgment: We would like to take this opportunity to express our sincere thanks to Plasma Quo
funding from Ministerio de Economía y Competitividad de España.
[1] Ye, X. ; Jin, L.; Caglayan, H.; Chen, J.; Xing, G.; Zheng, C.; Doan-Nguyen, V.; Kang, Y.; Engheta,
N.; Kagan, C.; Murray, C. B. ACS Nano, 2012, 6, 2804–2817.
77
O1.9
Shearing as a driven Force to direct the Assembly of Nanocomposites Films
B. Martín-García*, M. M. Velázquez
Dpto. Química-Física, Universidad de Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain
*
[email protected]
From a technologically point of view, the fabrication of thin films of quantum dots
(QDs)/polymer nanocomposites is an important issue for the development of solar cells, LEDs
and sensors. Focusing the attention on the Langmuir-Blodgett technique, the monolayers
prepared by compression usually lead to metastable states and space-filling defects. A way to
avoid these states and promote the formation of more ordered and homogeneous films is the
application of successive compression-expansion cycles [1]. Besides, to ensure a good
processability and reliability of the mixed QD/polymer films, it is important the study of their
dynamic properties. The Langmuir trough has been proposed as a good platform to carry out
the study of the dynamics of thin films. In this field, there is little work with nanoparticle
monolayers [1-3] and to best of our knowledge for mixed systems only studies realized with
surfactants and nanoparticles exist [4]. In the case of nanoparticle/polymer systems theoretical
studies are only available [5,6]. Therefore, we study the influence of the shearing on the mixed
QD/polymer film morphology and dynamic processes involved in the reorganization
following a previous work [7] focused on the characterization of Langmuir and LB films of
these systems.
Brewster angle microscopy allows us to observe in situ the movements and
association processes in the monolayer promoted by shearing [8]. The compression step
induces compact domains while the expansion step generates cracks that propagate in the
perpendicular direction to the applied stress. To analyze the effect of compression cycles on
the film morphology we transfer by LB technique the monolayers after shearing. AFM and
TEM images showed that the LB film becomes more close-packed, being the effect more
marked at high strains, and that the QDs affect the interactions between polymer molecules
and consequently, the polymer LB film morphology [6]. Finally, the analysis of the monolayer
dynamics after shearing, highlighted two relaxation processes for QDs and mixed QD/polymer
films: the fastest one was ascribed to rafts motions, and the slowest, related to movements
inside rafts. The time-scales of these processes depend on the film composition, thus the
slower relaxations correspond to systems with high polymer mole fraction probably due to
impediments on the polymer matrix.
Acknowledgements: The authors thank financial support from ERDF and MEC (MAT 2010-19727). B.M.G.
thanks European Social Fund and Junta de Castilla y León for the FPI grant. The authors want to thank
especially to Dr. J.A. Pérez-Hernández and C.L.P.U. for the AFM measurements and Electron Microscopy
Service (University of Salamanca) for TEM facility.
[1] Kim, J. Y.; Raja, S.; Stellacci, F. Small 2011, 7, 2526-2532.
[2] Cicuta, P.; Vella, D. Phys. Rev. Lett. 2009, 102, 138302.
[3] Zang, D.; Langevin, D.; Binks, B. P.; Wei, B. Phys. Rev. E 2010, 81, 011604.
[4] Guzmán, E. et al. J. Phys. Chem. C 2011, 115, 21715-21722.
[5] Toepperwein, G. N.; Riggleman, R. A.; de Pablo, J. J. Macromolecules 2012, 45, 543-554.
[6] Ghanbari, A. et al. Macromolecules 2012, 45, 572-584.
[7] Martín-García, B.; Velázquez, M. M. Mat. Chem. Phys. Submitted.
[8] Hilles, H.; Monroy, F.; Bonales, L. J.; Ortega, F.; Rubio, R. G. Adv. Colloid Interface Sci. 2006, 122, 6777.
78
O1.10
Dissolution of ZnO nanoparticles in aqueous media:
A first essential step in nanotoxicological studies
C. Rey-Castro1,*, C. David1, S. Cruz-González1, J. Salvador1, F. Mas2, J. Puy1 and J. Galceran1
1
2
Departament de Química and AGROTECNIO. Universitat de Lleida (Spain)
Departament de Química Física and IQTCUB. Universitat de Barcelona (Spain)
*
[email protected]
Dissolution of inorganic nanoparticles is one of the most relevant processes in the study of
the environmental and toxicological impact of these materials. In first place, it determines their
persistence in natural waters. Secondly, dissolution leads to the release of metal ions that may be
potentially harmful for living organisms. Indeed, the relative importance of dissolved ions and
particles on the overall toxic effect is still under debate. In this work, we present a review of the
main physicochemical factors that affect the kinetics of dissolution and equilibrium solubility of
ZnO nanoparticles [1], i.e.: pH, particle size and concentration, temperature, aggregation/
agglomeration, interaction with dissolved ligands and natural organic colloids (humic acids). The
release of Zn2+ ions was probed by the new electroanalytical technique AGNES (Absence of
Gradients and Nernstian Equilibrium Stripping) [2], which does not require a solid-liquid
separation step (as opposed to conventional solubility methods). The concentration of labile Zn
species in solution was also analyzed by the dynamic speciation technique DGT (Diffusive
Gradients in Thin Films) [3], and the results were compared with elemental analysis of centrifuged
fractions by ICP-OES. The stability, agglomeration state and particle size distributions of the
samples were characterized by UV-vis spectroscopy, Laser Doppler Electrophoresis, Dynamic
Light Scattering, and plunge-freeze Transmission Electron Microscopy.
Figure caption: Equilibrium free Zn2+ concentration in buffered dispersions of ZnO at 0.1M ionic strength and 298K,
determined by AGNES.
Acknowledgements: The research leading to these results has received funding from the European Union 7th
Framework Programme (FP7/2007-2013) under grant agreements n° 229244 (ENNSATOX) and nº 310584
(NANoREG), from Spanish Ministry of Education and Science (Projects CTQ2009-07831 and CTM201239183), and from Generalitat de Catalunya” (2009SGR00465). R. Wallace and N. Hondow (Institute for
Materials Research, U. of Leeds, UK) carried out the plunge-freeze TEM analysis.
[1] David, C. ; Galceran, J.; Rey-Castro, C.; Puy, J.; Companys, E.; Salvador, J.; Monné, J.; Wallace, R.;
Vakourov, A. J. Phys. Chem. C, 2012, 116, 11758.
[2] Companys, E.; Puy, J.; Galceran, J. Environ. Chem., 2007. 4, 347.
[3] Mongin, S.; Uribe, R.; Rey-Castro, C.; Cecília, J.; Galceran, J.; Puy, J. Environ. Sci. Technol. 2013 in press
79
O1.11
pH Responsive Nanoparticles for Intracellular Release of Doxorubicin
Shahla Bagherifam1,2,3,*, Vasif Hasirci1, Bo Nyström2, Gareth W. Griffiths3,
Gunhild M. Mælandsmo4, Nesrin Hasirci1
1
BIOMATEN-Center of Excellence in Biomaterials and Tissue Engineering, Ankara 06800, Turkey
2
3
Institute of Molecular Biosciences University of Oslo, University of Oslo, Oslo, Norway
4
Institute for Cancer Research, Oslo University Hospital, University of Oslo, Oslo, Norway
*
[email protected])
Chemotherapy is a common aspect of cancer treatment, which is usually applied by
using mostly cytotoxic anti-cancer agents [1]. Non selectivity of chemotherapeutic agents
causes to kill cancerous cells as well as normal cells, especially cells in tissues such as hair,
skin, and blood cells that are replaced fast. In the last decades, various nano-sized delivery
systems have been developed to be applied in cancer treatment. The newest approach is design
of smart and nano-size formulations to target anti-cancer agent to a specific part of the body.
This presentation concerns the use of polysebacic anhydride for anti-cancer agent delivery.
For this purpose, polysebacic anhydride was first synthesized and then used to prepare
nanocapsules (NC) loaded with the anti-cancer drug doxorubicin (DOX). To promote an
intracellular release and to obtain pH
responsibility, the prepared nanocapsules were
coated by poly L-histidine (PLH). The size and
morphology of both coated and non coated
nanocapsules were analyzed by scanning
electron microscopy (SEM) and dynamic light
scattering (DLS). The antitumor activity,
intracellular release and cell uptaking of
formulated nanocapsules were examined on
MDA-MB-231 human breast cancer cells.
Figure 1 shows that free DOX primarily enters
into MDA-MB-231cells and it easily localizes
in the nuclei as it has been demonstrated
previously [2]. For cells treated with PLH
coated NCs, a significant increase of
intracellular release of DOX was observed
(Figure - c).
Figure caption: Confocal microscopy images for intracellular release of DOX; a) non-treated cells b)
cells treated by free DOX c) cells treated by pH responsive NCs
[1] Bonetti A, et al., A phase I-II study. Tumor 2006; 92, 389-95
[2] Zhang C et al., Biomaterials 2012; 33, 2187-96
80
O1.12
Solid trivalent metal dodecyl sulfates: from aqueous solution to lamellar
Rui F.P. Pereira1,*, Artur J.M. Valente1, Ricardo A.E. Castro2, Hugh D. Burrows1 and
V. de Zea Bermudez2
1
Dept. of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal.
Faculty of Pharmacy, University of Coimbra, 3004-295 Coimbra, Portugal
3
Dept. of Chemistry and CQ-VR, University of Trás-os-Montes e Alto Douro, 5001-801 Vila Real,
Portugal.
*
[email protected]
2
Colloidal systems involving long chain anionic amphiphiles and trivalent metal ions form
ordered nanostructures through self-assembly. These systems have considerable potential in
materials science, including tunable UV/visible light emitters, templated synthesis of mesoporous
materials, production of lanthanide-based glasses for photonic applications, preparation of
nanoparticles, and formation of metal–organic frameworks (MOFs) and layered lamellar solids.
The ability to predict and tune the structure and ordering of self-assembled nanostructures leads to
the development of a wide range of useful materials with enhanced physical properties.[1]
The addition of trivalent metal salts to sodium dodecyl sulfate (SDS) in aqueous solutions
almost invariably leads to precipitation, due to formation of the trivalent metal dodecyl
sulfates.[2,3] Metal dodecyl sulfates of trivalent aluminium, chromium, lanthanum and gadolinium
were prepared by addition of the corresponding salts to aqueous solutions of SDS at the natural pH
(ca.6). XRD, FT-IR and NMR spectroscopy, DSC, TGA and polarizing light thermomicroscopy
demonstrate that metal dodecyl sulfates are formed with lamellar structures. These have different
degrees of hydration, which depend upon the metal ion. In some cases there is evidence for
coexistence of different lamellar phases. The metal is strongly bound electrostatically to the sulfate
group, and although the alkyl chain is in an extended conformation, there are suggestions of local
disordering of the methylene groups adjacent to the anionic head group. Studies by SEM and AFM
provide evidence of periodicity, which is likely to be induced by the lamellar, layered structures.
Differences are observed in the thermal behavior, which appear to reflect both the coordination
behavior of the metal ion and the degree of hydration.
Figure caption: Surfactant-metal ion superstructures. [3]
Acknowledgements: MEC, FEDER, FCT and COMPETE are thanked for financial support through the
projects MAT2008-06079/MAT and Pest-C/CTM/LA0011/2011. R.F.P.P. thanks FCT for a Ph.D. grant
(SFRH/BD/38696/2007).
[1] Xia, F.; Jiang, L., Adv. Mater. 2008, 20, 2842–2858.
[2] Pereira, R. F. P.; Tapia, M. J.; Valente, A. J. M.; Burrows, Langmuir 2012, 28, 168-177.
[3] Pereira, R. F. P.; Valente, A. J. M.; Burrows, H. D.; de Zea Bermudez, V.; Carvalho, R. A.; Castro,
R. A. E., RSC Advances 2013, 3, 1420-1433.
81
O1.13
Protein-nanoparticle bionconjugates: Enhanced protein stability and inhibition
of fibrillogenesis
S. Goy1, A. Topete1, A. Cambón1, E. Villar-Alvarez1, N. González1, M. Alatorre-Meda1,
E. Casals2, V. F. Puntes2, S. Barbosa1,*, P. Taboada1, V. Mosquera1
1
Grupo de Física de Coloides y Polímeros, Facultad de Física, Universidad de Santiago de Compostela,
15782, Santiago de Compostela, Spain
2
Institut Catalá de Nanotecnología, Campus UAB, 08913 Bellaterra-Barcelona, Spain
*
[email protected]
Gold nanoparticles (Au NPs) from 5 to 100 nm in size synthesized with HAuCl4 and
sodium citrate were complexed with the plasma protein human serum albumin (HSA). Size,
surface charge, and surface plasmon bands of the Au NPs are largely modified by the
formation of a protein corona via electrostatic interactions and hydrogen bonding as revealed
by thermodynamic data. Negative values of the entropy of binding suggested a restriction in
the biomolecule mobility upon adsorption. The structure of the adsorbed protein molecules is
slightly affected by the interaction with the metal surface, but this effect is enhanced as the NP
curvature decreases. Also, it is observed that the protein molecules adsorbed onto the NP
surface are more resistant to complete thermal denaturation than free protein ones as deduced
from the increases in the melting temperature of the adsorbed protein. Differences in the
conformations of the adsorbed protein molecules onto small (<40 nm) and large NPs were
observed on the basis of -potential data and FTIR spectroscopy, also suggesting a better
resistance of adsorbed protein molecules to thermal denaturing conditions. We think this
enhanced protein stability is responsible for a reduced formation of HSA amyloid-like fibrils
in the presence of small Au NPs under HSA fibrillation conditions.
Figure caption: Scheme showing the stabilizing effect of Au NPs on HSA fibrillation
82
O1.14
Enzymatic Modulation in the Growth of Gold Nanorods: Ultrasensitive
detection of acetylcholinesterase inhibitors
Marc Coronado-Puchau1,*, Laura Saa1, MarekGrzelczak1,2, Valery Pavlov1, Luis Liz-Marzán1,2
1
CICbiomaGUNE, Paseo de Miramón 182, Donostia – San Sebastián.Spain
2
*
[email protected]
Gold nanorods have become one of the most interesting nanostructures for biosensing
and imaging applications due to their unique tunable optical properties. In this study we
describe a simple enzymatic assay based on the modulation of the seeded growth of gold
nanorods [1], which can be used for the detection of trace amounts of acetylcholinesterase
inhibitors. Acetylcholinesterase is a hydrolytic enzyme that is able to decompose
acetylthiocholine to generate the thiol-bearing molecule thiocholine [2]. Since it is well known
that thiols can covalently bind to gold nanoparticles (NPs), one expects that the so-formed
thiocholine molecules inhibit further NP growth. Therefore, gold nanorod seeds were first preincubated with different concentrations of enzymatically produced thiocholine and then such
seeds were added to the growth solution of gold nanorods. It was found that the resulting
longitudinal surface plasmon resonance (LSPR) band of gold nanorods is sensitive to the
concentration of thiocholine and a progressive change in the intensity and position of this band
was observed. TEM images of the resulting NPs suggested that the modulation of LSPR
position is due to the existence of 3 different NP shapes (rods, cubes and spheres), resulting in
a different optical response depending on the percentage of each shape of NPs. Hence,
different enzyme concentrations can be correlated with different plasmon bands and/or gold
NP shapes. Finally, this assay was also used for the detection of subnanomolar concentrations
of diethyl 4-nitrophenyl phosphate (paraoxon), a typical acetylcholinesterase inhibitor. In view
of these findings, we propose to use this system as a simple colorimetric assay for the
ultrasensitive detection of acetylcholinesterase inhibitors.
Figure caption: Scheme showing the effect of enzymatically produced thiocholine on the shape of gold NPs.
[1] Pérez-Juste, J.; Pastoriza-Santos, I.; Liz-Marzán, L. M.; Mulvaney, P. Coord. Chem. Rev., 2005, 249,
1870-1901.
[2] A.Virel; L; Saa; V. Pavlov, Anal. Chem., 2009, 81, 268–272.
83
O1.15
Nanoparticles and nanodroplets as templates for inorganic synthesis:
Crystallization at surfaces and interfaces
Rafael Muñoz-Espí*, Viktor Fischer, Hasan Samet Varol, and Katharina Landfester
Max Planck Institute for Polymer Research, Ackermannweg 10, 55118 Mainz, Germany
*
[email protected]
Colloidal systems have a great potential as supports and templates for the formation
of inorganic and organic–inorganic hybrid nanostructures [1]. On one hand, colloidal particles
(both polymeric and inorganic) can act as a support for crystallization processes on their
surface. On the other hand, the colloidal structures generated by micelles and surfactantstabilized droplets serve as soft templates or nanoreactors for the controlled precipitation of
inorganic materials. Here, we will focus on the versatility of miniemulsions for these two
strategies.
We have shown that inorganic/polymer hybrids can be prepared by in-situ formation
of metal oxide (CeO2, Fe2O3, Fe3O4, ZnO) nanocrystals on the surface of polystyrene particles
functionalized with hydrophilic groups [2]. The polymer particles are synthesized by
miniemulsion copolymerization. The inorganic crystallization is achieved by adding a
precipitating agent to a suspension of the polymer particles loaded with a metal precursor. The
approach can be carried out in both aqueous and alcoholic media, which implies that it can be
extended to a wide range of inorganic materials, including different chalcogenides. In this
sense, we have also succeeded on preparing a “second generation” of multifunctional particles
containing a magnetoresponsive inorganic component (Fe3O4) on the core and a lightresponsive functionality (CdS) on the surface [3].
In addition to liquid–solid interfaces provided by polymer colloids in suspension,
miniemulsions can also offer liquid–liquid interfaces that can be used to form inorganic
hollow particles by soft templating. We reported before that sol–gel processes can be driven to
the interface of miniemulsion droplets to form amorphous capsules of hydrous zirconia and
hafnia [4]. Now, we present that interfacial crystallization can directly occur under mild
conditions (even at room temperature) for different transition metal oxides and hydroxides.
[1] Muñoz-Espí, R.; Mastai. Y; Gross, S.; Landfester, K. CrystEngComm 2013, 15, 2175–2191.
[2] Fischer, V.; Lieberwirth, I.; Jakob, G.; Landfester, K.; Muñoz-Espí, R. Adv. Funct. Mater. 2013, 23,
451–466.
[3] Fischer, V.; Bannwarth, M. B.; Jakob, G.; Landfester, K.; Muñoz-Espí, R. J. Phys. Chem. C 2013,
117, 5999–6005.
[4] Hajir, M.; Dolcet, P.; Fischer, V.; Holzinger, J.; Landfester, K.; Muñoz-Espí, R. J. Mater. Chem.
2012, 22, 5622–5628
POLYMERS, POLYELECTROLYTES, SURFACTANTS AND GELS
84
O2.1
Non-equilibrium Kinetics in Block Copolymer Micelles Observed by millisecond
Time-Resolved SAXS and SANS
Reidar Lund1,*
1
Dept. of Chemistry, University of Oslo Postboks 1033 Blindern, 0315 Oslo,Norway.
*
[email protected]
The kinetics of block copolymer micelle is still not fully understood [1]. Such
processes include both equilibrium kinetics, e.g. molecular exchange, and non-equilibrium
kinetics associated with morphological transitions and the formation of micelles. Earlier we
have focussed on the formation kinetics where we showed that the kinetic pathway is
characterised by a nucleation & growth type mechanism where unimer (single) chain is the
dominating fundamental step [2]. Here we focus on the structural and kinetic aspects of a
cylinder-to-sphere structural transition occurring in a model amphiphilic block copolymer
system upon variation of the interfacial tension. We demonstrate that the transition is
governed by entropic chain stretching in the core, which is more prominent at high interfacial
tensions. We further show that we can directly follow these transitions in the real time by
small angle scattering using both neutrons (TR-SANS, D11, ILL) and by x-rays (TR-SAXS,
ID02, ESRF) by applying a stopped-flow apparatus for rapid mixing. The results show that the
cylinders typically rapidly dissociates into spherical micelles within some few hundreds of
milliseconds and thereafter reorganize to the final equilibrium spherical micelles within
seconds. Interestingly, the transition seems to be driven by instabilities over the whole
cylinder leading to fragmentation, which is followed by reorganization and growth of these
entities into final spherical micelles. This contrasts earlier studies where the cylinders were
suggested to decompose from the (more) unstable ends [3]. The opposite transition is not
possible where the system rather ends up in a into another spherical micellar state. We will
discuss this behaviour in connection with some recent results on the respective “equilibrium”
exchange kinetics that can be accessed using time resolved SANS [1]. We will try to
interrelate and discuss kinetic pathways in block copolymer micelles and how this insight
might be used to create cost-effective nano-particles.
[1] Lund, R.; Willner, L.; Richter, D. Adv. Polym. Sci., 2013 (in press).
[2] Lund, R.; Willner, L.; Monkenbusch, M.; Panine, P.; Narayanan, T.; Colmenero, J.; Richter, D.
Phys. Rev. Lett., 2009, 102, 188301.
[3] Burke, S; Eisenberg, A. Langmuir, 2001, 17, 6705.
85
O2.2
A unique colloidal “crystal-gel” structure observed in microgravity conditions
Juan Sabín1,*, Arthur E. Bailey2, Gabriel Espinosa3, Barbara J. Frisken2
1
Department of Applied Physics, University of Santiago de Compostela, Spain
2
Department of Physics, Simon Fraser University, Canada.
3
Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, México
*
[email protected]
Colloids serve as model systems to study a wide range of phases and phase kinetics.
The addition of polymer to colloid solutions induces an attractive depletion force between the
colloidal particles and leads to a rich phase diagram where coexistence of gas-crystal, gasliquid-crystal and gas-liquid phases is possible [1]. One advantage of studying phase behavior
in colloid-polymer systems is that the colloid-colloid interaction potential can be precisely
tuned by changing the size and concentration of the polymer relative to those of the colloid.
On the other hand, gravity effects may be minimized to mimic atomic systems. We have
studied the interplay between phase separation and crystallization in a colloid-polymer
mixture along one kinetic pathway in samples which exhibit three-phase equilibrium
coexistence. In analogy with atomic systems, the range of the effective attractive interaction
between colloids is sufficiently long to allow for a stable liquid phase. By direct imaging in
microgravity on the International Space Station, we observe a unique structure, a ''crystal gel,''
that occurs when gas-liquid phase separation arrests due to crystallites within the liquid
domain spanning the cell [2].
Figure caption: Image of a sample which exhibit a gas-liquid-crystal coexistence in Earth 30 hr after
homogenization.
Acknowledgements: We gratefully acknowledge contributions by astronauts Robert Thirsk and Shannon
Walker, the Canadian Space Agency (CSA) and NASA BCAT-5 teams, Financial support was received
from the CSA, the Spanish Government, and NSERC of Canada.
[1] Ilett, S. M.; Orrock, A.; Poon, W. C. K.; Pusey, P. N. Phys. Rev. E 1995, 51, 1344-1352.
[2] Sabin, J.; Bailey, A. E.; Espinosa, G.; Frisken, B. J. Phys. Rev. Lett. 2012, 109, 195701.
86
O2.3
pH-response and crosslinking time effect on chitosan nanofilms
Jonathan Miras1,*, Chao Liu2, Eva Blomberg2, Esben Thormann2, Eric Tyrode2,
Susana Vílchez1, Jordi Esquena1, Karin Persson3, Per Claesson2
1
Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, and CIBER of Bioengineering,
Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
2
Surface and Corrosion Science Division, Department of Chemistry, Royal Institute of Technology
(KTH), Stockholm, Sweden
3
SP Chemistry, Materials and Surfaces, Stockholm, Sweden
*
[email protected]
Smart textile materials offer a wide range of high added-value applications, for use in
different non-conventional sectors such as technical, biomedical or sportwear [1]. An
innovative strategy for functional finishing of textile materials is based on the incorporation of
a thin polymer film, which is made of stimuli-sensitive hydrogels [2, 3]. This kind of
hydrogels shows response to external stimuli (i.e. pH, temperature, light, electric or magnetic
field) allowing its application in a wide range of biomedical fields: delivery of therapeutic
agents, tissue engineering, biological sensors, etc [4]. In this context, chitosan is especially
interesting, since it is obtained by deacetylation of chitin, the second most abundant
polysaccharide found in nature. It is a green biopolymer due to its excellent biocompatibility,
biodegradability, non-toxicity, cationic character and low cost [5]. The purpose of the present
study was to evaluate pH and crosslinking dependence of chitosan films, using a natural and
non-toxic crosslinking agent, genipin. For this purpose, three different techniques were used
for surface characterization of chitosan crosslinked films placed on flat silicon surfaces:
dynamic contact angle, quartz crystal microbalance with dissipation (QCM-D) and atomic
force microscopy (AFM). Contact angle determinations showed the hydrophilic behavior of
these films, with values lower than 50º. The variation in contact angle was related to film
swelling at acidic pH (protonation of amino groups of chitosan), and film shrinkage at basic
pH (deprotonation of amino groups). Moreover, contact angle measurements allowed us to
study the influence of crosslinking time, observing a reduction in swelling by increasing
crosslinking time. The pH-response of chitosan nanofilms was also studied by QCM-D and
AFM. The results confirmed that swelling and shrinking reduced due to long crosslinking time
as pH change, indicating the formation of more rigid nanofilms. QCM-D showed a lower
change in frequency and dissipation than that described by other authors [6], probably due to
the high crosslinking leading to higher rigidity of these nanofilms. AFM observations showed
that roughness did not vary as a function of pH, which was also attributed to the high
crosslinking of these chitosan films.
[1] Textor, T.; Mahltig, B., Appl. Surf. Sci. 2010, 256, 1668-1674.
[2] Jocic, D., Res. J. Text. Apparel 2008, 12, 58-65.
[3] Kulkarni, A.; Tourette, A.; Warmoeskerken, M. M. C. G.; Jocic, D., Carbohydrate Polymers 2010,
82, 1306-1314.
[4] Mano, J. F., Adv. Eng. Mater. 2008, 10, 515-527.
[5] Rinaudo, M., Prog. Polym. Sci. 2006, 31, 603-632.
[6] Lee, H. S.; Yee, M. Q.; Eckmann, Y. Y.; Hickok, N. J.; Eckmann, D. M.; Composto, R. J., J. Mater.
Chem. 2012, 22, 19605-19616.
87
O2.4
Molecular Dynamic Simulations of Conjugated Polyelectrolytes with Surfactants
in Solvent Environments
Beverly Stewart1,*, Joana Pragana1, S. M. Fonseca1, T. Costa1, A. T. Marques1,2, U. Scherf2
and H. D. Burrows1
1
Departamento de Química, Universidade de Coimbra, Portugal..
Macromolecular Chemistry Group, Bergische Universität, D-42119 Wuppertal, Germany
*
[email protected]
2
The high efficiencies observed in photosynthetic light harvesting systems are based
on their elegant self-assembled structures. In order to mimic these structures in synthetic
systems it is required to both control and understand aggregation.
Here the use of molecular dynamic simulation is presented as a method by which to
observe the behaviour of small fluorene based conjugated polyelectrolyte (CPE) structures [1].
Interest lies primarily in the study of both anionic and cationic charged polyelectrolyte species
and their observed aggregation behavior as well as the significance of surfactant presence
upon this aggregation. Dynamic simulations have thus far indicated that aggregation of CPEs
in inhibited in the presence of non-ionic oxyethylene based surfactants [2], CmEn by way of
separating the CPEs and encapsulating them in liquid crystalline surfactant phases. Here the
effects of CmEn as well as polyvinyl alcohol (PVA) as a known water soluble polymer are
examined as aggregation inhibitors. The importance of various inter- and intra-molecular
interactions, as well as solute environments will be discussed as contributing factors in the
production of well-defined aggregated structures. Experimental findings are also included to
form an overall representation of the process. In the presence of PVA, an increase in
fluorescence quantum yield and a blue shift in the emission maximum of PBS-PFP are
observed. This behaviour is similar to that observed with oxyethylene surfactants, suggesting
that the CPE is incorporated as isolated chains into CPE-PVA aggregates.
Figure caption: Encapsulation of CPE by Polyvinyl Alcohol
Acknowledgements: The authors thank Professor A.A.C.C. Pais for valuable discussions and the FCT for
financial support through Postdoctoral Grants to BS, SMF and TC and a Ph.D. grant to ATM.
[1] Burrows, H. D.; Tapia, M. J.; Fonseca, S. M.; Pradhan, S.; Scherf, U.; Silva, C.L.; Pais, A. C. C.; Valente,
A. J. M.; Schillén. K.; Alfredsson, V.; Carnerup. M.; Tomiši, M.; Jamnik, A., Langmuir 2006, 25, 55455556.
[2] Burrows, H. D.; Fonseca, S. M.; Silva, C.L.; Pais, A. C. C.; Tapia, M. J.; Pradhan. S.; Scherf, U., Phys.
Chem. Chem. Phys 2008, 10, 4420-4428.
88
O2.5
Nanostructure of cationic surfactant-DNA complexes
Amalia Mezei1,*, Ramon Pons1, M. Carmen Morán2
1
Department de Tecnologia de Tensioactius, IQAC-CSIC, Barcelona, Spain;
Department de Fisiologia. Facultat de Farmacia, Universitat de Barcelona, Barcelona, Spain.
*
[email protected]
2
Nanostructured materials have opened new possibilities for application in novel
sensors, biomaterials, drug delivery and delivery vehicles. In the last years increasing interest
is focused on the structure of oppositely charged macromolecules and surfactants. The strong
electrostatic attraction between the negative charges of DNA and the positive charge of the
surfactant aggregates is forming complexes. The properties of cationic surfactants and DNA
gel particles has been characterized recently [1-3]. However, the nanostructure of these
complexes is still not clear. In the present communication an overview about the preparation
and nanostructure of thin films based on four different cationic surfactants and DNA is
proposed. Three different preparation methods were investigated, the obtained films were
washed with water, dried at room temperature and analyzed by polarized light microscopy and
X-ray measurements. A representative image of the textures obtained from polarized light
microscopy is shown in Figure 1. The experimental results of X-ray measurements suggest a
hexagonal packing in these complexes. Further insight into the structural properties of the
complexes was obtained by Elemental Analysis from which the surfactant/base molar ratio
was calculated. Different DNA helices to surfactant rods arrangement have been obtained in
the complexes ranged to 2:1 or 3:1 depending on the surfactant structure. This research could
be the basis for new drug-delivery applications of thin films.
(a)
(b)
(c)
(d)
Figure caption: Representative optical polarized micrographs of cationic surfactant-DNA complexes:
(a) CTAB-DNA; (b) MTAB-DNA, (c) ALA-DNA and (d) LAM-DNA.
The scale bar in (a) correspond to 50m.
Acknowledgements: This work was supported by CSIC trough a JAE-DOC2010-097 contract cofinanced by FSE 2007-2013. Financial support by CTQ2010-14897 from MINECO (Spain) and
2009SGR1331 from Generalitat de Catalunya is acknowledged. M.Carmen Morán acknowledges the
support of the MICINN (Ramon y Cajal contract RyC 2009-04683). Imma Carrera is acknowledged for
technical assistance and Jaume Calles for IQAC SAXS-WAXS Service and the Microanalysis Service
from IQAC.
[1] Morán, M. C.; Miguel, M. G.; Lindman, B., Langmuir 2007, 23, 6478-6481.
[2] Morán, M. C.; Miguel, M. G.; Lindman, B., Soft Matter 2010, 6, 3143-3156.
[3] Morán, M. C.; Infante M. R.; Miguel, M. G.; Lindman, B., Pons R., Langmuir 2010, 26, 1060610613.
89
O2.6
Micellar Shape Transition in an Imidazolium based-surfactant
Pedro Rodríguez-Dafonte1,*, María Figueira-González1, Vitor Francisco1, Luis García-Río1,
Eduardo F. Marques2, and Mercedes Parajó1
1
Centro Singular de Investigación en Química Biológica y Materiales Moleculares, Department of
Physical Chemistry, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain
2
Centro de Investigacǜão em Química, Department of Chemistry and Biochemistry, Faculty of Sciences,
University of Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal
*
[email protected]
The self-aggregation behavior of an ionic liquid, the double-chained surfactant 1,3didecyl-2-methylimidazolium chloride ([C10C10mim]Cl), in aqueous solution has been
investigated with a number of different experimental techniques. Two critical micelle
concentration values (cmc1 and cmc2) are obtained from these techniques. The cmc1 value
corresponds to the formation of spherical micelles and cmc2 to the transition from spherical to
cylindrical micelles. Finally, at an even higher concentration of ionic liquid, a third structural
evolution is detected, from cylindrical micelles to bilayer aggregates.
Conductivity measurements of [C10C10mim]Cl in aqueous solutions were performed
at different temperatures. The specific conductivity () plotted as a function of surfactant
concentration show two slope changes that are assigned to two different critical micelle
concentrations. The values of the fraction of surfactant counterions bound to the micelle ()
were obtained.
The structural change in the shape of the aggregates was confirmed by diffusionordered NMR spectroscopy (DOSY), from the self-diffusion coefficients for surfactant unimer
and aggregates. Furthermore, a third evolution from cylindrical micelles to bilayer aggregates
is proposed from the analysis of diffusion coefficients at high surfactant concentration (> 0.2
M).
Isothermal Titration Calorimetry (ITC), at temperatures between 278.15 K and
318.15 K, was used in order to obtain the corresponding standard thermodynamic parameters
of micellization.
N
N
2
N
cmc1
N
0
N
N
'H (kJ/mol)
Monomers
SphericalMicelles
-2
-4
-6
-8
-10
0
0.2
0.4
0.6
0.8
[C10 C10 mimCl] /mM
Figure caption: Enthalpogram of C10C10mimCl in water, T=288.15 K
90
O2.7
Binding of cationic single-chain/dimeric surfactants to bovine serum albumin.
Influence of the number of hydrophobic chains and the presence of aromatic
rings on protein-surfactant interactions
María Luisa Moyá*, Victoria I. Martín, Alfredo Maestre and Amalia Rodríguez,
Department of Physical Chemistry, University of Seville, C/Profesor García González 1, 41012 Sevilla.
*
[email protected]
Proteins are important in living organisms and take part in many life processes. They can
bind a wide variety of ligands such as bilirubin, fatty acids, hematin, metal ions, drugs and
surfactants. Interactions of proteins with surfactants have been extensively studied because their
mixtures have important applications in biosciences, foods and cosmetics, drug delivery, detergents
and biotechnological processes [1]. It has been established that the developing protein–surfactant
interaction may alter the original functional properties of the protein. This means that not only the
solubility or the aggregation properties, but also the conformational parameters of the protein may
be modified. The interaction between bovine serum albumin, BSA, and the single-chain surfactants
N-benzyl-N,N-dimethyl-N-(1-dodecyl)ammonium bromide (PH12) and N-cyclohexylmethyl- N,Ndimethyl-N-(1-dodecyl)ammonium bromide (CH12) and their two dimeric counterparts N,N'-(1,3phenylenebis(methylene))bis(N,N-dimethyl-N-(1-dodecyl)ammonium dibromide (12PH12) and
N,N'-(cyclohexane-1,3-diylbis(methylene))bis(N,N-dimethyl-N-(1-dodecyl)ammonium dibromide
(12CH12) have been investigated by surface tension, fluorescence, circular dichroism, zeta
potential and atomic force microscopy. The results obtained permit the examination of how an
increase in the number of hydrophobic chains and the substitution of a cyclohexyl ring by a phenyl
ring, either in the head group of single-chain surfactants or in the spacer of dimeric surfactants,
affect BSA-surfactant interactions. Comparison of fluorescence results with those obtained by zeta
potential measurements shows differences in the binding sites of the surfactants with and without
aromatic rings to the protein.
(a)
(b)
(c)
(d)
Figure caption:-AFM topographic image of BSA-surfactant solutions, at pH=7 phosphate buffer, adsorbed on
MgCl2 modified and non modified mica surface. a)Pure BSA (1 g/L); b)12CH12 0.01 M ; c)12CH12 5x10-5 M
+ BSA 1 g dm-3; d)12CH12 0.01 M+ BSA 1 g/L.
Acknowledgments. This work was financed by the DGCYT (grant CTQ2009-07478), the European Union and
Consejería de Innovación, Ciencia y Empresa de la Junta de Andalucía (FQM-274 and P07-FQM-03056).
[1] Mishra, M.; Muthuprasanna, P.; Prabha, K. S.; Rani, P. S.; Babu, I. A. S.; Chandiran, I. S.; Arunachalam,
G.; Shalini, S. Int. J. PharmTech. Res. 2009, 1, 13541365.
SOFT COLLOIDS. SOFT NANOTECHNOLOGY. BIOINSPIRED SYSTEMS
91
O3.1
Monoolein-based liposomes for siRNA delivery
Ana C. N. Oliveira1,2, Thomas Martens3,4, Koen Raemdonck3, Andreia C. Gomes1,
Kevin Braeckmans3,4, M. E. C. D. Real Oliveira2,*
1
Center of Molecular and Environmental Biology, University of Minho, 4710-057 Braga, Portugal
2
Center of Physics, University of Minho, 4710-057 Braga, Portugal
3
Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmacy, Ghent University,
Harelbekestraat 72, 9000 Ghent, Belgium
4
Centre for Nano- and Biophotonics, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
*
[email protected]
Gene silencing by introducing small interfering RNAs (siRNAs) into cells is a promising
therapeutic strategy for the treatment of various pathologies. In this study we propose monoolein (MO)based liposomes, already validated for plasmid DNA delivery [1-3], as potential vehicles for siRNA
delivery. It was previously shown that the inclusion of MO in liposome formulations results in
nanoparticles with different structures depending on the DODAB:MO lipid molar fractions [4], which
influences the in vitro performance of the lipidic carriers [2, 3]. In the present work, four formulations
composed by dioctadecyldimethylammonium bromide (DODAB) or chloride (DODAC) and MO, at
different cationic:neutral lipid molar ratios (2:1 and 1:2), were prepared and evaluated in order to assess
their potential as in vitro siRNA nanocarriers. MO-based lipoplexes were found to be smaller than 150
nm and are highly positively charged, which favorably contributed to the high internalization as
quantified by flow cytometry and confirmed by confocal microscopy (Figure 1). Cellular uptake
experiments showed that internalization mainly happens through endocytosis, although a small fraction
might internalize through direct fusion with the plasma membrane. DODAC:MO lipoplexes were more
cytotoxic at higher charge ratios than their DODAB:MO counterparts, while the presence of more MO
did not increase the toxicity of the formulations. The most efficient formulation in cellular transfection
was DODAB:MO (2:1). This work shows the potential of using MO in siRNA delivery systems, and
reinforces the importance of the selection of cationic lipids with the adequate counter ions to produce
optimized particles for the intended use.
Figure caption: - Intracellular distribution of Cy5-labeled siRNA-lipoplexes after 4 h incubation with H1299 cells.
Red – siRNA-labeled lipoplexes; Green – endo/lysosomal compartments; Blue – cell nucleus.
Acknowledgements: This work was supported by FEDER through POFC – COMPETE and by national funds from
FCT through the project PEst-C/BIA/UI4050/2011 (CBMA) and PEst-C/FIS/UI0607/2011 (CFUM) and also funding
through projects PTDC/QUI/69795/2006 and SFRH/BD/46968/2009.
[1] Real Oliveira, M. E.C.D. et al. Use of Monoolein as a New Auxiliary Lipid in Lipofection, in International Patent
WO2010/020935, W.I.P. Organization, 2010. p. 1-27.
[2] Neves Silva, J.; Oliveira, A.; Casal, M.; Gomes, A.; Coutinho, P.; Coutinho, O.; Real Oliveira, M.E.C.D.,
Biochim. Biophys. Acta 2011, 1808, 2440-2449.
[3] Neves Silva, J.; Oliveira, A.; Gomes, C.; Real Oliveira, M. E. C. D., Development of
Dioctadecyldimethylammonium Bromide/Monoolein Liposomes for Gene Delivery. In Cell Interaction; Dr.
Sivakumar Gowder (Ed.), InTech, 2012, Chapter X, pp 1-28
[4] Oliveira, I.; Neves Silva, J.; Feitosa, E.; Marques, E.; Castanheira, E.; Real Oliveira, M. E. C. D., J. Colloid
Interface Sci. 2012, 374, 206-217.
92
O3.2
The cooperative interaction between hydrophobically modified inulin
and DDAB
J. Morros1,*, M. R. Infante1, M. G. Miguel2, B. Lindman2, R. Pons1
1
Institut de Química Avançada de Catalunya (IQAC-CSIC),Barcelona, Spain..
2
Departamento de Química da FCTUC, Coimbra, Portugal.
*
[email protected]
As petroleum feedstock decreases, the development of new renewable bio-based and
efficient chemicals has attracted more and more interest. Recently, a natural polydisperse
polysaccharide named inulin has gained considerable attention. This polysaccharide extracted
from chicory roots consists mainly of ß(2-1)-fructosyl furanose units, and has unique
properties due to its linear structure and its rather low molecular weight range in comparison
to other polysaccharides such as cellulose and starch.
This relatively small polymer has focused special interest when several hydrophobic
chains are attached on its backbone [1]. This hydrophobically modified inulin (HMI) is able to
stabilize many dipersed systems such as o/w emulsions, solid dispersions or films by steric
stabilization mechanisms [2]. Additionally, it possesses other important properties like surface
activity comparable to those of molecular surfactants or thermo-reversible associative
behaviour in aqueous solutions. Also, the hydrophobic groups grafted onto the polyfructose
backbone tend to aggregate in order to limit their contact with the solvent leading to the
formation of stable core-shell soft nanoparticles [3].
In the present work, we explore the interaction of these macromolecular structures
with a well-known vesicle forming cationic surfactant, didodecyldimethylammonium bromide
(DDAB). Initially, one could expect that HMI would stabilize vesicles by the already
described steric stabilization mechanisms, but surprisingly this is not the case. Helped by
characterization techniques, we have elucidated the nature of these polymer-surfactant
interactions by proposing interaction models for surface tension, zero-shear viscosity and
SAXS profiles. Here, we present our results with several synthesized HMIs [4] together with
pristine inulin (without hydrophobic modifications) and Inutec®SP1 (commercial HMI) for
comparative reasons, and we propose some possible applications for these interesting mixed
micelles formed by DDAB and HMI.
Acknowledgements: This research was financially supported by a Bilateral Project (P2007PT0050), a
COST project (COST-STSM-D36-05462), Mineco (CTQ2010-14897 and MAT2012-38047-C02-02)
and Generalitat de Catalunya (CTQ2009-SGR1331). Technical support provided by J. Caelles and I.
Carrera for SAXS measurements and Surface Tension measurements, respectively, is especially
acknowledged. And thank you for the selflessly material support of Beneo BBC in this research.
[1] Stevens, C. V.; Meriggi, A; Peristeropoulou, M; et al., Biomacromolecules 2001, 2, 1256–1259.
[2] Tadros, T. F.; Vandamme, A.; Levecke, B.; et al., Adv. Colloid Interface Sci. 2004, 108, 207-226.
[3] Morros, J.; Infante, M. R.; Pons, R., Soft Matter 2012, 8, 11353-11362.
[4] Morros, J.; Levecke, B.; Infante, M. R. Carbohydrate Polymers 2010, 82, 1168-1173.
93
O3.3
Polymeric nano-emulsions obtained by low-energy methods and their use for
nanoparticle templating
M. Homs, G. Calderó* and C. Solans
Department of Chemical and Biomolecular Nanotechnology, Colloid and Interfacial Chemistry group,
Institute of Advanced Chemistry of Catalonia (IQAC-CSIC) and Centro de Investigaciones Biomédica en
Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain.
*
[email protected]
Nano-emulsions are emulsions with droplet size in the range of 20-200 nm [1]. They
are commonly prepared by high-energy methods (e.g. applying external energy input).
However, they can be also obtained by low-energy methods (e.g. using the internal chemical
energy of the components), which produce generally, smaller and more uniform droplets than
high-energy methods [1-3]. Nano-emulsions prepared by low-energy methods can be
advantageous for the preparation of polymeric nanoparticles. However, some parameters as
the effect of polymer nature and its concentration as well as the use of partially water soluble
solvents on nano-emulsion size and stability remain to be understood. The aim of this work
was to study the effect of composition parameters on the stability and characteristics of the
polymeric nano-emulsions and on the nanoparticles obtained using these nano-emulsions as
templates. Polymeric oil-in-water (O/W) nano-emulsions were prepared in water/nonionic
surfactant/[polymer in ethylacetate] systems by stepwise addition of water to the remaining
components at 25ºC (phase inversion composition, PIC, method). Nano-emulsions with a
water content of 90 wt% and different oil-surfactant (O/S) weight ratios were selected for
these studies. The mean hydrodynamic radius of droplets was in the range of 10-100 nm
depending on the polymer concentration and the O/S ratio. Stability studies showed that no
sedimentation or creaming was produced as assessed
by light transmittance/backscattering determinations.
Polymeric nanoparticles prepared from nanoemulsions by the solvent evaporation method [4]
revealed, as expected, mean sizes slightly lower than
those of the corresponding template nano-emulsions
due to the solvent evaporation. The results obtained
together with the biocompatibility of the components
selected make these nanoparticles of interest for
biomedical applications.
Figure caption: Visual aspect of an (O/W) nano-emulsion
and schematic representation of the nanodroplets
[1] Solans, C.; Izquierdo, P.; Nolla, J.; Azemar, N.; García-Celma, M. J. Curr. Opin. Colloid Interface
Sci., 2005, 10, 102-110.
[2] Tadros, Th.; Izquierdo, P.; Esquena, J.; Solans, C. Adv. Colloid Interface Sci., 2004, 108-109, 303318.
[3] Solans, C.; Solè, I. Curr. Opin. Colloid Interface Sci., 2012, 17, 246-254.
[4] Calderó, G.; García-Celma, M. J.; Solans, C. J. Colloid Interface Sci., 2011, 353, 406-411.
94
O3.4
Stable capsules formed by liposomes coated by the layer-by-layer method
Ramón G. Rubio1,*, Marta Ruano1 and Francisco Ortega1
1
Department of Physical Chemistry, Faculty of Chemistry, Complutense University, 28040-Madrid,
Spain.
*
[email protected]
Nano- and microcapsules are important as delivery systems as well as microreactors.
[1] It has been frequent to make the by using a particle as template, coating it with polymers,
and finally dissolving the template. In the case of inorganic templates the last step implies to
work under chemically aggressive conditions (e.g. use of HF for silica particles). In the case of
polymer templates it cannot be ensured that all the polymer chains have diffused out of the
capsule.[2] In this communications we describe a simple method to coat liposomes (neutral or
charged) with polymers and/or particles using the layer-by-layer method. Figure 1 illustrates
the coating procedure.
Figure caption: Scheme of the coating process of a liposome using the layer-by-layer method. PAH:
poly(diallyl dimethyl ammonium) chloride. PSS: sodium poly(styrene sulfonate).
Different pairs of polyelectrolytes (PAH, PSS, PGA, PLL) and also charged latex
particles have been used for building the multilayers. Mixtures of phospholipids (DOPC,
DPPC) and a cationic (DODAB) have allowed us to use both cationic liposomes
(DOPC+DODAB) over a broad surface charge density range, and zwitterionic liposomes. The
number of layers and the nature of the polymers determine the diffusion through the wall of
the capsule, as well as its stability. Capsules with up to ten polymer layers have been produced
that remained stable for months, and resisted centrifugation. The diffusion of a dye through
the capsule wall has been studied.
Acknowledgements: This work has been supported by MINECO under grant FIS2012-38231-C02-01, by
COST Action CM1101, and by ESA under grants FASES and PASTA.
[1] Caruso, F. L, J. Amer. Chem. Soc. 1998, 120, 1
[2] Sukhorukov, G. D.; Donath, E.; Davis, S. Polym. Adv. Technol. 1998, 9, 8
95
O3.5
Serine-based catanionic liposomes as potential nanocarriers for molecular
delivery
Sandra G. Silva, David Félix, M. Luísa C. do Vale, Eduardo F. Marques*
Centro de Investigação em Química (UP), Department of Chemistry and Biochemistry, Faculty of
Science, University of Porto, Rua do Campo Alegre s/n, P-4169-007, Porto, Portugal.
*
[email protected]
The use of amino acids for the synthesis of surfactants with potential liposome-forming
properties opens the route to the design of novel biofriendly liposomes that can aim at the
controlled delivery of drugs, proteins and nucleic acids [1]. These liposomes can be based inter alia
on single-surfactant systems, mixed surfactant/lipid systems or catanionic surfactant mixtures. In
the latter case, the liposomes often possess several advantageous features, such as enhanced
chemical and colloidal stability, as well as the possibility of charge control [2,3].
In recent years, we have addressed the synthesis and physicochemical characterization of
a variety of ionic amino acid-based surfactants [4,5]. Herein, we report the phase behavior and
microstructure of serine-based catanionic mixtures composed by single-chained cationic (C12,
C16) and double-chained anionic (C8-8, C12-12) surfactants. Synthesis of the compounds has been
performed according to a previously reported methodology [5]. Phase maps for the C12/C12-12
and C16/C8-8 mixtures are available, where regions of liposome formation can be identified.
Characterization of aggregate morphology, zeta potential and stability as a function of the
cationic/anionic surfactant mixing ratio, and total surfactant concentration, has been performed by
DSC, tensiometry, video-enhanced light microscopy (VELM), dynamic light scattering, cryo-SEM
and cryo-TEM. A
rationalization of the
structural
evolution
between aggregates as
function of mixture
composition
is
presented, on the basis
of geometric packing
and
electrostatic
effects.
Figure caption: A – Cryo-SEM and B – VELM micrographs of 16Ser/8-8Ser liposomes;
C – Surface tension curves for the neat surfactants and two catanionic mixtures.
Acknowledgements: Thanks are due to the Portuguese Science Foundation (FCT) and FEDER-Compete for financial
support through PTDC/QUI-QUI/115212/2009, REDE/1517/RMN/2005 and Pest/C-QUI/UI0081/2011. S.G.S. also
acknowledges FCT for PhD grant SFRH/BD/61193/2009.
[1] Colomer, A.; Pinazo, A.; Manresa, M. A.; Vinardell, M. P.; Infante, M. R.; Pérez, L. J. Med. Chem. 2011, 54, 9891002.
[2] Marques E. F., Surfactant Vesicles, in Encyclopedia of Surface and Colloid Science, 2nd ed., Taylor & Francis
2010, 1-19.
[3] Silva, B. F. B.; Marques, E. F.; Olsson, U., Soft Matter, 2011, 7, 225-236.
[4] Brito, R. O.; Silva, S. G.; Fernandes, R. M. F.; Marques, E. F.; Rodriguez-Borges, J. E.; Vale, M. L. C., Colloids
Surf. B 2011, 86, 65-70.
[5] Silva, S. G.; Rodríguez-Borges, J. E.; Marques, E. F.; do Vale, M. L. C., Tetrahedron 2009, 65, 4156.
96
O3.6
Soft Particles for Tunable Nanophotonics
Ana Maldonado-Valdivia1, Benjamín Sierra-Martín1, Antonio Fernández-Barbero1,*
1
Group of Complex Fluids Physics and NanoLab,
University of Almería, 04120 Almería, Spain.
*
[email protected]
Metal nanoparticles and tailored surfaces exhibit optical properties which differ
remarkably from those from bulk materials. One of them is the localized surface plasmon
resonance. This phenomenon becomes apparent when an external electromagnetic field
incident on a metal element (nanoparticles, nanovoids, …) induces electron cloud
delocalization. Net charge difference on surfaces acts as restoring force, producing in the
simplest case dipolar oscillation. Optical response is originated from the strong localized
metal absorption when the frequency of the electromagnetic fields becomes resonant with the
coherent electron motion. One of the most challenging problems concerning the photonics of
nanoparticles and surfaces is the possibility of modulating the optical properties through
external inputs. In this context, merging of metal and smart-soft-polymer technology to make
hybrid systems leads to very successful results. In this talk, tunable optical surfaces based on
soft-particles and soft-hybrid-particles photonic nanovoids are presented.
Acknowledgements: This work has been funded by the Spanish Ministerio de Economía y
Competitividad/FEDER (project MAT2011-28385), Andalusian Government/FEDER (Project P010FQM 06104) and EU-COST-Action CM1101.
COLLOIDS AND ENERGY
97
O4.1
A rheological study of magnetic fluids based on highly viscoelastic solvents
J. P. Segovia-Gutiérrez*, R. Hidalgo-Álvarez and J. de Vicente
Department of Applied Physics, Faculty of Sciences, University
of Granada, C/ Fuentenueva s/n, 18071-Granada, Spain.
*
[email protected]
Wide range application of magnetic field-controllable (smart) materials is
impeded by several limitations. Most, if not all of these limitations are currently
associated with the fluids themselves, as opposed to the device design and
manufacturing [1]. Undoubtedly, one of the most important challenge concerns
particle sedimentation/aggregation and colloidal stability. In order to tackle this
challenge and enhance the rheological properties, a large number of approaches and
strategies have been followed in the past by using highly bidisperse fluids, ferrofluidbased colloids, two-phase emulsions and thixotropic physical gels [2]. A detailed
experimental study is described in this work on the impact of polymer-colloid
interactions in magnetorheological performance. To this end, a mixture [3] is
investigated that provide a highly non-Newtonian character to the dispersing medium.
Viscoelastic fluid
Viscoelastic fluid + CI 5 vol%
Viscoelastic fluid+ CI 5 vol% + H0=259 kA/m
2
K (Pa·s)
10
1
10
0
10
0
200
400
600
800
1000
-1
Shear Rate (s )
Figure caption: Shear viscosity as a function of the shear rate for three different situations. CI means
Carbonyl Iron and H0 represents the external magnetic field applied on the normal direction to the flow.
Acknowledgements: This work was supported by the MICINN MAT 2010-15101 project (Spain), the
European Regional Develop-ment Fund (ERDF) and the Junta de Andalucía P09-FQM-4938, P10-FQM5977, P10-RNM-6630 and P11-FQM-7074 projects (Spain). J.P. S.-G. acknowledges financial support
by the ”Ministerio de Educación: Becas del Programa de Formación del Profesorado Universitario
(FPU)” (AP2008-02138). J. de V. and R. H.-A. thank the financial support received from CEI-Biotic
20F12/16.
[1] Klingenberg, D. J., AIChE Journal 2001, 47, 246-249.
[2] de Vicente, J.; López-López, M. T.; González-Caballero, F.; Durán J. D. G., J. Rheol. 2003, 47,
1093-1109.
[3] Stokes J. R., Swirling flow of viscoelastic fluids. Research Collections (UMER), 1998.
COLLOIDS AND ENERGY
98
O4.2
Band gap engineering with subnanometric metal (0) clusters:
catalytic, electrocatalytic & photocatalytic applications
M .A. López-Quintela1,*, N. Vilar-Vidal1,2, D. Buceta3, M. C. Blanco1 and J. Rivas2
1
Laboratory of Magnetism and Nanotechnology (Nanomag), Technological Research Institute,
University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain
2
INL-International Iberian Nanotechnology Laboratory. 4715-330 Braga. Portugal.
3
Chemistry Department. Brookhaven National Laboratory 11973, Upton, NY, USA.
*
[email protected]
Metal clusters formed by a small number of metal (0) atoms represent a novel state of
matter, located between the classical bulk (or nanoparticle) behaviour and the different behaviour
of the corresponding atoms. In the last years we have developed simple, efficient and scalable soft
chemical routes for the production of metal (0) clusters of Au, Ag, Pt, and Cu, based on the use of
kinetic control. Such techniques allow the production of relative monodisperse clusters, Mn, in the
range 1< n< 50 (i.e. with sizes < 1-2nm), without using strong ligand agents, which can inhibit
many of their interesting properties.
Different catalytic studies with metal clusters have shown that these tiny compounds open
up new horizons and opportunities of research concerning the development of a completely new
family of novel catalytic materials, able to cover a broad range of green reactions related with: 1)
the substitution of oxidants by oxygen in green chemistry, including the partial and total oxidation
by molecular oxygen of alcohols, olefins and thiols at room temperature and aerobic conditions,
etc.; 2) the electrocatalysis in fuel cells, including hydrogen and alcohol electrooxidation, as well as
the oxygen reduction reaction, and 3) the photocatalytic conversion of solar light for driving
chemical reactions, with especial attention to the light driven production of hydrogen by water
splitting and detection and photodecomposition of contaminants (see figure below). A summary of
the most recent results in this area of catalysis with atom-level resolution, using a common
framework for -until now- almost unrelated different catalysis fields, will be provided in this talk.
Figure caption: Selective Pb2+sensoring and its photocatalytic UV-elimination by Cu13 clusters (left).
Self-explained energy diagram of the observed sensing and selectivity (right).
Acknowledgements: We want to acknowledge the financial support of the MCI and Xunta de Galicia,
Spain (MAT2010-20442; Grupos Ref.Comp. 2010/41, respectively).
SURFACES AND INTERFACES
99
O5.1
NMR self-diffusion studies on the binding and exchange dynamics between
block copolymers and carbon nanotubes
Ricardo Fernandes1,2, Michael Shtein3,, Ilan Pri Bar3, Oren Regev3, István Furó2, and
Eduardo F. Marques1,*
1
Centro de Investigação em Química, Department of Chemistry and Biochemistry, Faculty of Science,
University of Porto, Rua do Campo Alegre, s/n, P-4169-007 Porto, Portugal.
2
Division of Applied Physical Chemistry, Department of Chemistry, KTH Royal Institute of Technology,
SE-10044 Stockholm, Sweden.
3
Department of Chemical Engineering and the Ilse Katz Institute for Nanotechnology, Ben-Gurion
University of the Negev, 84105 Beer-Sheva, Israel
*
[email protected]
Carbon nanotubes (CNTs) are emerging materials with a wealth of applications in
different areas, ranging from molecular devices and sensors, to nanocomposites and drug delivery.
However, pristine CNTs tend to bundle into strongly bound aggregates due to van der Waals
interactions. This is a drawback, since major applications often require individually dispersed
CNTs. One possibility to overcome this issue is by the use of non-covalent dispersants (surfactants,
polymers or biomolecules), which are able to exfoliate and stabilize CNTs in aqueous solution.
Despite active research in the field, non-covalent dispersion is still poorly understood at molecular
level [1].
In what concerns polymers as dispersants, two main qualitative models on the polymerCNT interaction are available. In one, the polymers coat the CNT in a tight contact referred to as
wrapping. In the other, a loose adsorption is proposed, in which a weaker interaction between the
polymer and the CNT takes place, so that the bound polymer remains almost like in its natural state
in a good solvent, i.e. in a random coil.[2]
In this work, we have studied by 1H NMR diffusometry the exchange dynamics between
the CNT surface and the bulk of triblock copolymers Pluronic® F127, F87 and F68 (of general
structure (PEO)m(PPO)n(PEO)m, where m=65 and n=100 for F127; m=61 and n=41 for F87; m=76
and n=29 for F68) and single walled nanotubes (SWNT). A non-monoexponential 1H echo decay is
observed for all polymers, that changes character upon change in the diffusion time , which
indicates a situation where the exchange time lies on the experimental time scale (). The initial
fast decay corresponds to the “freely”-diffusing polymer in the bulk, while the slow decay is
associated with CNT-bound polymer. Thus, for instance, the self-diffusion coefficient of F127 in
CNT-adsorbed state is found to be of the order of 2.2 × 10-12 m2.s-1, ca 30-fold smaller than that
obtained for the unbound polymer in water (5.9 × 10-11 m2.s-1). The possibility of lateral diffusion of
the polymer coil on the CNT surface being at stake has been systematically investigated. For all
polymers studied, one observes that the major polymer fraction is in the free-state, while a small
fraction is adsorbed onto the nanotube, with a characteristic average residence time.[3] A
correlation between the polymer residence time and the relative PEO/PPO block size will be
presented. Overall, the results seem to support the “loose adsorption” model for polymer-CNT
interaction.
Acknowledgements: Thanks are due to the Portuguese Science Foundation (FCT) and FEDER-Compete for financial
support through project PTDC/QUI-QUI/115212/2009 and Centro de Investigação em Química (CIQ-UP) through
project Pest/C-QUI/UI0081/2011. RF also acknowledges FCT for the Ph.D. grant SFRH/BD/72612/2010. The
Swedish Research Council VR is also kindly acknowledged.
[1] Wang, H. Curr. Opin. Colloid Interface Sci. 2009, 14, 364-371.
[2] Granite, M.; Radulescu, A.; Pyckhout-Hintzen, W.; Cohen, Y. Langmuir 2011, 27, 751-759.
[3] Frise, A. E.; Pages, G.; Shtein, M.; Pri Bar, I.; Regev, O.; Furó, I. J. Phys. Chem. B 2012, 116, 2635-2642.
100
O5.2
Probing in-vitro digestion of interfacial protein structures in a single droplet
Julia Maldonado-Valderrama1,*, Juan A. Holgado Terriza2, Amelia Torcello-Gómez1 and
Miguel A. Cabrerizo-Vílchez1
1
Applied Physics Department. Campus de Fuentenueva sn, 18071. University of Granada, Spain.
2
Department of Sofware Engineering, C/Periodista Daniel
Saucedo Aranda, sn, 18071, University of Granada, Spain.
*
[email protected]
This study has been designed to investigate the effects of gastrointestinal digestion on
protein covered interfaces. We have used a new device, fully designed and assembled at the
University of Granada: the OCTOPUS, which provides a customised static sequential in vitro
digestion process in a single droplet. The evolution of the interfacial tension throughout the whole
simulated gastrointestinal transit is measured in-situ and the mechanical properties of the interfacial
layer (interfacial dilatational modulus) after each digestion stage. The in-vitro digestion model used
here focuses on pepsinolysis and lipolysis of two dairy proteins: -lactoglobulin (BLG) and casein (BCS) adsorbed at the olive oil–water interface. The results show different susceptibilities of
interfacial layers of BLG and BCS to pepsinolysis; while pepsinolysis of adsorbed BLG weakens
the interfacial network, pepsinolysis of adsorbed BCS strengthens it as measured by the dilatational
moduli. These numbers provide an interfacial scenario for previous findings on emulsification of
these proteins, which was found to improve BLG pepsinolysis but somehow protected BCS from
pepsinolysis in the stomach. The desorption profiles provide quantification of the extent of lipid
digestion in subsequent simulated intestinal fluid containing lipase. The extent of lipid hydrolysis
was found to be similar in BLG and BCS covered interfaces and comparable to that in the absence
of coverage (pure oil–water interface) indicating that proteins do not comprise a barrier to lipolysis.
This is attributed to the similar interfacial properties of the interfaces reaching the duodenum
despite the structural differences between native BCS and BLG, thus demonstrating the impact of
the transit through the gut on lipolysis. This research allows identification of the interfacial
mechanisms affecting enzymatic hydrolysis of proteins and lipolysis. The results can be exploited
in tailoring novel food matrices with improved functional properties such as decreased digestibility,
controlled energy intake and low allergenicity.
Figure caption: Detail of the exchange procedure. Interfacial tension following in-vitro digestion of BLG
adsorbed at the olive oil-water interface.
Acknowledgements: This work has been sponsored by the EU-FP7-PERG07-GA-2010-268315-ColloDi
and projects JCI-2009-03823, MAT2010-20370 and MAT2011-23339 (MICINN), P08-FQM-4325 and
P09-FQM-4698 (Junta de Andalucía) and CEI-Biotic 20F12/16 and Microproyecto2013(UGR).
[1] Maldonado-Valderrama, J.; Holgado-Terriza, J. A.; Torcello-Gómez, A.; Cabrerizo-Vílchez, M. A.,
Soft Matter, 2013, 9, 1043-1053.
101
O5.3
Effect of porosity and surface material in the transport of ions across
nanoporous alumina membranes
V. Romero1, V. Vega2, J. García2, R. Zierold3, K. Nielsch3, V. M. Prida2, B. Hernando2,
J. Benavente1,*
1
Dpto. Física Aplicada I, Facultad Ciencias, Universidad Málaga, E-29071-Málaga, Spain.
2
Dpto. de Física, Facultad de Ciencias, Universidad de Oviedo, E-33007-Oviedo, Spain.
3
Institut für Angewandte Physik, Jungiusstrasse 11, D-20355 Hamburg, Germany.
*
[email protected]
Nanoporous Anodic Alumina Membranes (NPAMs) synthesized via electrochemical
anodization of aluminium are formed by self-ordered structures with parallel aligned and well
defined pores keeping honeycomb structure geometry [1]. The excellent chemical and thermal
stability of NPAMs favor their use in separation processes, mainly when heavy metal or
corrosive products are involved, while their practically ideal porous structure allows them to
be considered as model systems for the study of mass and ions transport [2]. Moreover,
NPAMs are also employed in biosensor construction and drug-delivery applications, but
problems associated to surface hydrophobicity and the lack of biocompatibility are factors of
significant importance, although they might be over-passed by surface coating with adequate
materials [3].
The objective of this work is to establish the effect of both inter-pore distance/porosity
and surface nature in the transport of ions though NPAMs. For these reasons four nanoporous
membranes were chosen: i) two NPAMs with similar pore radii (~ 10 nm) but different
porosity (10 % (AL-Sf) and 37% (ANP)) and suppliers; ii) two NPAMs with similar pore
radii and porosity (~ 6 nm and 3 %, respectively) but modified surfaces by ADL deposition of
Al2O3 (AL-Sf/Al2O3) or SiO2 (AL-Sf/SiO2) nanoparticles coating layers. Membrane potentials
measurements were performed using NaCl solutions at different concentrations (0.002 M to
0.1 M) for all the NPAMs. The differences among them give significant information on the
effect of pore size, porosity and pore/membrane surface nature on ions diffusion coefficients
(D+ and D-) across the nanopores and the membrane effective charge (Xef) as it can be seen in
Table 1.
Table 1: Effective fixed charge (Xef), average porosity 4!and pore radii <rp> and ionic diffusion
coefficients (D+ and D-).
membrane
Al-Sf
ANP
Al-Sf/Al2O3
Al-Sf/SiO2
Xef (M)
20.0x10-3
0.9x10-3
24.0 x10-3
3.0x10-3
11
10
6
6
rp!nm
10
37
3
3
4! (%)
D+ (m2/s)
2.1x10-10
1.0x10-9
2.0x10-10
7.2x10-10
2
-9
-9
-9
D- (m /s)
1.3x10
1.9x10
1.2x10
1.4x10-9
Acknowledgements: To CICYT (projects CTD2011-27770 (FEDER funds) and MAT2010-20798-C0504) for financial support. V. Romero also thanks to CICYT for her FPU grant.
[1] Eftekhari, A. Nanostructured Materials in Electrochemistry, Wiley-VCH, Weinheim, 2008.
[2] Romero, V.; Vega, V.; García, J.; Prida, V. M.; Hernando, B.; Benavente, J. J. Colloids Interface
Sci. 2012, 376, 40-46.
[3] Losic, D.; Cole, M. A.; Dollmann, B.; Vasilev, K.; Griesser, H. J. Nanotechnology 2008, 19, 245704.
102
O5.4
Bulk and interfacial Microrheology
Francisco Ortega1,*, Laura J. Bonales1, Armando Maestro1 , Nuria Mancebo1, Fernando
Martínez-Pedrero1, José E. Fernandez-Rubio1, Raquel Chuliá, Alma J. Mendoza1,
Ramón G. Rubio1
1
Departamento de Química Física I, Universidad Complutense de Madrid, Ciudad Universitaria s/n
Madrid, Spain
*
[email protected]
Micro and nanoreology [1,2] encompass a family of methods that uses micro- and
nanoparticles as mechanical probes of the rheological behavior of soft materials.
Microrheology presents several advantages over conventional mechanical rheology: smaller
size samples (aμL), use in heterogeneous samples (i.e. simultaneous measurement of several
environments), use in situ (e.g. cells), high throughput screening capability and very small
perturbation applied (in passive microrheology the thermal energy aKBT). The fact that the
applied stress is very small is of great importance when dealing with interfacial systems which
are very fragile soft materials.
We will discuss the experimental techniques [1,2] and the different procedures [3]
used to extract the complex shear modulus from the microrheological experiments. In this
discussion we will present results from two different 3D systems, agarose gel solutions and
pluronic solutions, and several monolayers (quasi-2D systems) of surfactants and polymers.
COST Action CM1101 and by ESA under grants FASES and PASTA.
[1] Waigh, T. A. Rep. Prog. Phys. 2005, 68, 685.
[2] Mason, T. G.; Weitz, D. A. Phys. Rev. Lett. 1995, 74, 1250
[3] Mason, T. G. Rheol. Acta, 2000, 39, 371.
103
O5.5
Segregation of silica particles with different size using driven receding contact
lines
Carmen L. Moraila-Martínez*, Miguel A. Cabrerizo-Vílchez and
Miguel A. Rodríguez-Valverde
Biocolloid and Fluid Physics Group, Department of Applied Physics, University of Granada, Campus of
Fuentenueva, E-18071 Granada, Spain.
*
[email protected]
The formation of solute deposits during the evaporation of sessile drops containing
complex liquids (solid particles, polymeric dispersions, emulsions) is recognized as a
multivariable process. The diversity in the deposit morphology is due to the complex
mechanisms behind the transport of particles during drop evaporation. It is known [1] that
small particles may be readily arranged at the vicinity of contact lines rather than larger
particles due to the wedge-like shape of the solid-liquid-air interfacial region (in hydrophilic
substrates). Although segregation effects in coatings are undesirable in many industrial and
scientific processes, the discrimination of particles with different size on a substrate can be
also fruitful [2].
The obscure contact line dynamics, the competition of inwards and outwards flows
within the evaporating drop and the increasing concentration of particles in bulk may hinder
the actual mechanisms that lead or mitigate the ring-like deposit formation. Recently, we have
developed a new methodology [3] to mimic the contact line dynamics of evaporating drops at
shorter times using a nonlinear suction from the drop bulk. With this methodology, referred to
as Controlled Shrinking Sessile Drop (CSSD), we are able to decouple the sustained
evaporation from the contact line motion, as Bodiguel et al. reported [4]. Unlike drop
evaporation, particle concentration in bulk remains constant for a CSSD experiment.
In this work, we studied the size dependent nano/microparticle separation near the
contact region of driven receding contact lines without macroscopic evaporation. We probed
the behavior of monomodal suspensions and binary mixtures of silica particles on a polymer
substrate with the CSSD methodology. To explore the particle segregation in ring-like
deposits, the electrostatic interactions (substrate-particle and particle-particle) were minimized
and the substrate receding contact angle was fixed. The height and width of the ring-like
deposits increased as the particle size whereas the ring diameter decreased as the particle size.
With the CSSD technique, smaller particles are able to penetrate further into the edge of the
drop. With these results, the application of the CSSD methodology with particle suspensions
may become a simple colloidal-assembly strategy.
Acknowledgements: This work was supported by the "Ministerio Español de Ciencia e Innovación"
(project MAT2011-23339) and the "Junta de Andalucía" (projects P08-FQM-4325 and P09-FQM-4698).
[1] Perelaer, J.; Smith, P. J.; Hendriks, C. E.; van den Berg, A. M. J.; Schubert, U. S. Soft Matter, 2008,
4, 1072–1078.
[2] Wong, T.-S.; Chen, T.-H.; Shen, X.; Ho, C.-M. Anal. Chem., 2011, 83, 1871–1873.
[3] Moraila-Martinez, C. L.; Cabrerizo-Vilchez, M. A.; Rodriguez-Valverde, M. A. Soft Matter, 2013, 9,
1664–1673.
[4] Bodiguel, H.; Doumenc, F.; Guerrier, B. Eur. Phys. J. Spec. Top., 2009,166, 29-32
104
O5.6
Ions-Induced Nanostructuration of Hydrophobic Polymer Surfaces
Carlos Drummond1,*, Igor Siretanu2, Delfi Bastos and Jean-Paul Chapel1
1
2
Centre de Recherche Paul Pascal, UPR8641 CNRS. Avenue Schweitzer, 33600 Pessac Cedex, France
Physics of Complex Fluids, MESA Institute for Nanotechnology, University of Twente, Post Office Box
217, 7500 AE Enschede, The Netherlands.
3
Biocolloid and Fluid Physics Group. Department of Applied Physics, University of Granada. Av.
Fuentenueva S/N, 18071 Granada, Spain
*
[email protected]
When hydrophobic surfaces are in contact with water in ambient conditions a layer of
reduced density is present at the interface, preventing the intimate contact between the two
phases. Reducing the extent of this layer by degassing the water promote ionic adsorption on
the hydrophobic. This process can induce long-lasting deformation of hydrophobic glassy
polymer films, a process called ion-induced polymer nanostructuration, IPN [1]. The selfassembled structure spontaneously relaxes back to the original flat morphology after few
weeks at room temperature. This instability and the self-assembled structure are controlled by
the hydrophobic surface charge, which is determined by the composition of the aqueous
phase, and by the amount of gas dissolved. We have found that this process is ion-specific;
larger surface modification is observed in the presence of water ions, hydrophobic and
amphiphilic ions. Surface structuration is also observed in the presence of certain salts of
lithium [2]. This effect can be easily adjusted to modify different hydrophobic polymeric
substrates at the submicrometer level, opening pathways for producing controlled patterns at
the nanoscale in a single simple waterborne step [3].
Figure caption: 1μmx1μm height tapping mode AFM micrographs taken in air of 300 nm thick 250 kDa
polystyrene films as prepared (spin-coated) (a); after exposure to a non degassed (b) and degassed (c)
solution of nitric acid in double distilled water at pH 1.5 and room temperature. A typical height profile
for each condition is presented. The presence of asperities of regular nanometric size is clearly observed
on the surface exposed to the degassed solution for 5 minutes. On the contrary, no modification was
detected when an identical film was exposed to the same solution under identical conditions before
removing the dissolved gases.
[1] Siretanu, I.; Chapel, J. P.; Drummond, C. ACSNano 2011, 5, 2939-47
[2] Siretanu, I.; Chapel, J. P.; Bastos-González, D.; Drummond, C. JPCB (Submitted)
[3] Siretanu, I.; Chapel, J. P.; Drummond, C. Macromolecules 2012, 45, 1001-05
105
O5.7
Quantum Dots onto Polymer and Surfactant self-assembled Films:
A Quartz Crystal Microbalance Study
T. Alejo*, M. D. Merchán and M. M. Velázquez
Departamento de Química Física, Facultad de Ciencias Químicas,
Universidad de Salamanca. 37008 Salamanca, Spain.
*
[email protected]
The study of the adsorption of nanomaterials onto surfaces has attracted extensive
interest considering the importance of the interactions of nanoparticles with polymeric or
biological templates. Thin polymer and surfactant films are used for applications as
microelectronic devices, solar cells, sensors, biomaterials or as adhesives, lubrication and
membranes. For nanocomposite material applications it is necessary to control the
incorporation of nanoparticles into the polymer films, the surface chemistry, spatial patterning
and physical properties. Quantum dots (QDs) nanocrystals are particularly interesting for its
applications in bioanalytics and optoelectronics [1]. Thus, in previous work we have studied
the properties of Langmuir and Langmuir-Blodgett monolayers prepared with the polymer
PMAO and Gemini surfactant 18-2-18 and QDs [2-3]. In this sense, Quartz Crystal
Microbalance with Dissipation monitoring (QCM-D) technique allow us to investigate the
kinetic self-assembly process of the molecules in an attempt to gain insight into the role of the
interaction between the organic molecules and nanoparticles. Moreover, it allows us to
measure the mass of the films adsorbed and its mechanical properties.
Firstly, the polymer and surfactant adsorption onto the SiO2 crystal sensor was
analyzed, showing a different amount of material adsorbed at the end of the process for the
polymer, the surfactant and their mixtures. Moreover, the dissipation factor (D) pointed to an
energetic adsorption in the polymer with shorter times. Meanwhile, in the surfactant and
polymer/surfactant mixtures the adsorption process showed a higher entropic contribution.
The dissipation factor values indicate than the polymer present a planar conformation of their
molecules at the interface while the surfactant and surfactant-PMAO mixtures give a higher
packing of molecules with their hydrocarbon chains oriented perpendicularly to the interface.
The analysis of the adsorption kinetics curves agrees with a bimodal adsorption process, in
which the first characteristic time is ascribed to a fast adsorption process of the molecules to
the surface of the sensor, meanwhile the second time corresponds to a reorganization process
of the molecules, corresponding to the slowest process with times of thousand of seconds.
From our results it is possible to conclude that the PMAO and Gemini surfactant increase the
QDs coverage compared with QDs films where the nanoparticles are directly adsorbed onto
the SiO2 sensor, leading to a greater coverage when the nanoparticles are adsorbed onto
polymer/surfactant mixtures.
Acknowledgements: The authors thank financial support from ERDF and MEC (MAT 2010/19727).
T.A. wishes to thank European Social Fund and Junta de Castilla y León for the FPI grant. The authors
want to thank especially to Drs J.A. Pérez-Hernández for the AFM measurements and C.L.P.U.
(University of Salamanca) for the AFM facility.
[1] Somers, R. C.; Bawendi, M. G.; Nocera, D. G. Chem. Soc. Rev., 2007, 36, 579-591.
[2] Alejo, T.; Merchán, M. D.; Velázquez, M. M.; Pérez-Hernández, J. A. Mater. Chem. Phys., 2012, 138, 286294.
[3] Alejo, T.; Merchán, M. D.; Velázquez, M. M. Thin Solid Films, 2011, 519, 5689-5695.
106
O5.8
Sudden Field Induced Sublimation In 2D Colloidal Crystallites
F. Martínez-Pedrero1,2,*, J. E. Fernandez- Rubio2, R. G. Rubio2 and F. Ortega2
1
CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
Universidad Complutense, Facultad de Química, Departamento de Química Física I,
Ciudad Universitaria, Madrid, Spain.
*
[email protected]
2
Colloidal particles absorbed at liquid interfaces are of interest in condensed-matter
physics in relation to a wide range of phenomena, including mechanism of ordering and selfassembly, vitrification, melt or sublimation processes in two dimensions (2D) [1]. In the
sublimation processes crystallites of finite size melt into a liquid or sublimate into a gas at a
steady rate from the perimeter, while the interior retains its crystalline order. Only below a
characteristic size, a metastable disordered phase seems to appear causing the rapid
vaporization of the system [2]. Here, we study the kinetics of sublimation in 2D crystallites
that occurs when dipolar repulsion is suddenly implemented between the constituent particles.
Contrary to these usual thermal processes, we found that in the field induced sublimation the
particles melt simultaneously through the entire crystal, at least for relatively high dipolar
interactions and tiny crystallites. A scaling behavior suggests a universal sublimation
mechanism for these small planar crystals in processes induced by strong enough repulsive
interactions. A second mechanism does not yet understood appears above a characteristic size,
which depends on the implemented repulsion between the particles.
Figure caption: Paramagnetic polystyrene colloidal beads of average diameter 3.9 m confined to the
water/air interface at 22°C. In the absence of the magnetic field the particles reversibly aggregate
through van der Waals and attractive capillary forces, forming ordered clusters through the field of view.
By implementing a strong enough magnetic repulsion, as compared with the attractive interactions
between the particles, a complete phase transition occurs and the mono-crystals rapidly go from an
ordered to a disordered state.
COST Action CM1101 and by ESA under grants FASES and PASTA. Research by F.M.P. has been
supported by a PICATA fellowship from the Moncloa Campus of International Excellence (UCMUPM).
[1] Bonales, L. J.; Martínez-Pedrero, F.; Rubio, M. A.; Rubio, R. G.; Ortega F., Langmuir 2012, 28,
16555-16566.
[2] Savage, J. R.; Blair D. W.; Levine A. J.; Guyer R. A.; Dinsmore A. D., Science 2006, 314, 795-798.
MODELING AND SIMULATIONS
107
O6.1
Stochastic diffusion of isotropic and liquid crystal phases of rodlike colloidal
particles: Monte Carlo and Brownian Dynamics meet
Alessandro Patti1,* and Alejandro Cuetos2
1
Institute of Advanced Chemistry of Catalonia (IQAC-CSIC) and CIBER de Bioingeniería, Biomateriales
y Nanomedicina (CIBER-BBN), Jordi Girona 18-26 - 08034 Barcelona, Spain.
2
Department of Physical, Chemical and Natural Systems,
Universidad Pablo Olavide, 41013 Sevilla, Spain.
*
[email protected]
Motivated by the growing interest on applying stochastic algorithms to investigate
the dynamics of equilibrium [1] and out-of-equilibrium [2] colloidal fluids, and by recent
attempts to mimic the Brownian Dynamics (BD) with Monte Carlo (MC) simulations [3,4],
we study the diffusion of merely repulsive and freely rotating colloidal rods in the isotropic,
nematic and smectic liquid crystal phases, to probe the agreement between Brownian and MC
dynamics under the most general conditions. By properly rescaling the MC time step, being
related to any elementary move via the corresponding self-diffusion coefficient, with the
acceptance rate of simultaneous trial displacements and rotations, we demonstrate the
existence of a unique Monte Carlo time scale that allows for a direct comparison between MC
and BD simulations. To estimate the validity of our theoretical approach, we compare the
mean square displacement of rods, their orientational autocorrelation function, and the selfintermediate scattering function, as obtained from Brownian dynamics and MC simulations.
The agreement between the results of these two approaches, even under the condition of
heterogeneous dynamics generally observed in liquid crystalline phases, is excellent [5].
Acknowledgements: A. P. acknowledges a Juan de la Cierva Grant No. JCI-2010-06943 from the
Spanish Ministry of Science and Innovation (MICINN) and a Beatriu de Pinós Grant No. 2009-BPB00058 from AGAUR. A. C. acknowledges funding from the Operative Programme FEDER-Andalucía
2007–2013 through Project No. P09-FQM-4938 and from MICINN through Project No. MAT201129464.
[1] Patti, A.; El Masri, D.; van Roij, R.; Dijkstra, M. Phys. Rev. Lett., 2009, 103, 248304.
[2] Berthier, L.; Kob, W. J. Phys.: Condens. Matter, 2007, 19, 205130.
[3] Sanz, E.; Marenduzzo, D. J. Chem. Phys., 2010, 132, 194102.
[4] Romano, F.; De Michele, C.; Marenduzzo, D.; Sanz, E. J. Chem. Phys., 2011, 135, 124106.
[5] Patti, A.; Cuetos, A. Phys. Rev. E. 2012, 86, 011403.
108
O6.2
Coarse-grained Monte Carlo simulations of thermo-responsive polyelectrolyte
nanogels
Manuel Quesada-Pérez1,*, José. A. Maroto-Centeno1 and Alberto Martín-Molina2
1
2
University of Jaén, Department of Physics (Spain).
University of Granada, Department of Applied Physics (Spain).
*
[email protected]
The classical formalism of gel swelling is not useful for networks of a few
nanometers when they are considered from a colloidal perspective because it is not possible to
consider the electric double layer around the polyelectrolyte network. In spite of this
limitation, coarse-grained simulations had not been applied to temperature-sensitive
polyelectrolyte nanogels yet, as far as we know. In this work, we have simulated thermoresponsive nanogels within the bead-spring model of polyelectrolyte and a solvent-mediated
hydrophobic interaction potential that captures the swelling behavior of real microgels[1].
Regarding the thermal response, our results qualitatively agree with those previously
published for macroscopic gels[2]. Charge profiles reveal that shrunken charged nanogels
form a hollow sphere, with the charged monomeric units concentrated on the inner and outer
surfaces, and some counterions accumulated in the inner space (see figure). Thus they really
behave as closed containers. Additionally, simulations show that the surface electrostatic
potential increases when temperature-sensitive nanogels shrink upon heating.
Counterion profiles were also calculated from a very simple Poisson-Boltzmann (PB)
cell model. Its predictions about the charge profile outside the nanogel, the fraction of
counterions inside and the surface electrostatic potential are in fair agreement with simulation
data. Thus, the PB cell model can provide useful information about the electric double layer of
thermo-responsive micro- and nanogels.
Figure caption: Cross section of a snapshot of a collapsed nanogel.
Acknowledgements: i) ‘Ministerio de Ciencia e Innovación, Plan Nacional de Investigación, Desarrollo e
Innovación Tecnológica (I+D+i)’, Projects MAT2012-36270-C04-04 and -02. ii) ‘Consejería de
Innovación, Ciencia y Empresa de la Junta de Andalucía’, Project P09-FQM-4698.
[1] Quesada-Pérez, M.; Ramos, J.; Forcada, J.; Martín-Molina, A.; J. Chem. Phys. 2012, 136, 244903.
[2] Quesada-Pérez, M.; Maroto-Centeno, J.A.; Martín-Molina, A.; Macromolecules 2012, 45, 8872.
109
O6.3
Effective electrostatic interactions arising in core-shell charged microgel
suspensions with added
A. Moncho-Jordá1,*, J. A. Anta2 and J. Callejas-Fernández1
1
Biocolloid and Fluid Physics Research Group, Departamento de Física Aplicada, Facultad de
Ciencias, Universidad de Granada, Campus Fuentenueva S/N, 18071 Granada, Spain.
2
Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, Carretera de
Utrera, Km 1, 41013. Sevilla, Spain.
*
[email protected]
The mixture formed by charged (ionic) microgels in the presence of 1:1 added salt,
with explicit consideration of a core-shell structure of the microgel particles, is studied [1]. By
solving numerically the three-component Ornstein-Zernike integral equations, the counterand coion penetration inside the microgel network and the resulting effective microgelmicrogel electrostatic interaction are calculated. This is done in the limit of very low microgel
concentration, so that the resulting pair-wise effective potential is not affected by many-body
particle-particle interactions. The ion-ion, microgel-ion and microgel-microgel correlations are
all treated within the Hypernetted-Chain (HNC) approximation. The results obtained clearly
show that the addition of salt to the microgel suspension has a deep impact on the screening of
the bare charge of the particles, confirming an already well-known result: the strong reduction
of the effective charge of the microgel occurring even for diluted electrolyte concentrations
[2]. We show that this effect becomes more important as we increase the shell size of the
particle, and derive a semi-empirical model for the effective charge as a function of the
electrolyte concentration and the shell extension. The resulting microgel-microgel effective
pair potential is analysed as a function of the shell extension and salt concentration. In all
cases the interaction is a soft potential when particles overlap. For non-overlapping distances,
our theoretical results indicate that microgel particles can be regarded as hard spherical
colloids bearing an effective charge given by the net charge inside the particle, and the
microgel-microgel interaction shows a Yukawa-like behaviour as a function of the
interparticle distance. It is also observed that increasing the bare-charge of the microgel
induces a strong microgel-counterion coupling in the limit of very low electrolyte
concentrations, which can not be justified using linearized theories. This leads to a even more
important adsorption of counterions inside the microgel network, and to a reduction of the
microgel-microgel effective repulsion.
Acknowledgements: The authors thank the MCINN (project MAT2009-13155-C04-02) and the Spanish
Ministerio de Economía y Competitividad (project MAT2012-36270-C04-02) for financial support.
[1] Moncho-Jordá, A.; Anta, J. A.; Callejas-Fernández, J., J. Chem. Phys. 2013, (accepted for
publication)
[2] Fernández-Nieves, A.; Wyss, H. M.; Mattsson, J.; Weitz, D. A., Microgel Suspensions:
Fundamentals and Applications. Wiley-VCH, Weinheim, 2011.
110
O6.4
Non-random adsorption of polyelectrolytes in regularly charged surfaces. From
single chain to multichain deposition
Sandra C. C. Nunes*, T. Firmino and A. A. C. C. Pais
Chemistry Department, University of Coimbra, Coimbra, Portugal.
*
[email protected]
The adsorption of polyelectrolyte chains onto different types of substrates is of great
relevance in biological and technological applications, making it the subject of many theoretical
and simulation studies. Different aspects ranging from molecular recognition to multilayer
deposition have been addressed. Despite the different works devoted to the broad topic of
polyelectrolyte adsorption, far less attention has been paid to the study of the factors controlling the
spatial distribution of these chains into homogeneous surfaces.
In the present study, Monte Carlo simulations were used to explore the conformation and
spatial distribution of uniformly charged polyelectrolytes adsorbing onto homogeneously
oppositely charged surfaces. A simple model was adopted, in which polyelectrolytes are
represented by spring-bead chains and the charged surface is taken to be a hard planar wall with
embedded positively charged fixed hard spheres. Variations were imposed in the surface area,
surface charge density and in the number and length of polyelectrolyte chains. The surface charge
in the different systems range from partially neutralized to reversed by backbone deposition.
Due to restrictions stemming from the interaction with the surface, polyelectrolytes
present, upon adsorption, a conformation different from that in the bulk. This was characterized by
the gyration radius, and by the number and length of tails, loops and trains. The spatial distribution
of the chains in surfaces was inspected resorting to positioning density maps and to metric
approaches based on proximity profiles.
Results indicate non-trivial effects on chain conformation upon adsorption and also nontrivial deposition patterns. As the surface area increases, the polyelectrolyte evolves from distended
conformations, only partially adsorbed, to a higher degree of adsorption in which compact
conformations are followed by more distended ones. However, high surface charge densities
impose, always, some degree of compaction, irrespective of the available space. Moreover for a
small number of surface charges, surfaces of lower charge density are able to adsorb more chain
segments.
Furthermore, it was found that the potential field created by these regularly charged
surfaces is non-uniform, thus promoting a preferential occupancy of some regions. These are
selected by a balance between the available space, maximization of the polyelectrolyte/surface
electrostatic interaction and minimization of the backbone bending penalty.
When exploring surface coverage with multiple chains, for a particular surface area,
adsorption occurs, tendentially, with a minimal effect upon the bulk conformation, in
configurations in which chain ends play a major role in the organization of the backbones upon
deposition. Moreover, adsorption into the most favorable regions of the surface overrides, to a large
degree, interchain repulsion.
Acknowledgements: This work was supported by FEDER funds through the COMPETE program - Programa
Operacional Factores de Competitividade - and by National funds through Fundação para a Ciência e
Tecnologia (FCT) under the Project PTDC/QUI-QUI/101442/2008 (COMPETE: FCOMP-01-0124-FEDER010831). Sandra C. C. Nunes gratefully acknowledges the post-doctoral research grant
SFRH/BPD/71683/2010 assigned by the Fundação para a Ciência e Tecnologia (FCT).
111
O6.5
A molecular insight on new vesicular systems formed by self-assembly of sterols
and quaternary ammonium surfactants
J. Faraudo1,*, L. Ferrer-Tasies1,2, E. Moreno-Calvo1,2, M. Cano-Sarabia1,2, M. Aguilella-Arzo3,
A. Angelova4, S. Lesieur4, S. Ricart1, N. Ventosa1,2, J. Veciana1,2
1
Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Esfera UAB; Campus UAB s/n;
E-08193 Cerdanyola del Vallès, Spain
2
CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN)
3
Biophysics Group, Department of Physics, Universitat Jaume I, E-12080 Castelló, Spain
4
Equipe Physico-chimie de Systèmes Polyphasés, UMR CNRS 8612, Univ Paris-Sud, 92296
Châtenay-Malabry, France.
*[email protected]
Thermodynamically stable nanovesicular structures are of high interest for academia and
industry in a wide variety of application fields, ranging from nanomaterials preparation to
nanomedicine.
In this contribution, we discuss a novel nanovesicular system, that we have called
quatsome [1], which has outstanding stability with time and temperature.. A quatsome is made by a
closed self-assembled bilayer of an amphiphilic bimolecular building-block. This building block is
made by the self-assembly of a quaternary ammonium surfactant and a sterol molecule (for
example a CTAB and a colesterol). As pure species, these surfactants (e.g. CTAB) form micelles
and insoluble cholesterol forms crystals in water. However, our molecular dynamic simulations
reveal a synergy between CTAB and cholesterol molecules, which makes them self-assemble into
bimolecular amphiphiles and then into bilayers in the presence of water. These bilayers have the
same structure of those formed by double tailed unimolecular amphiphiles.
In addition to MD simulations, we will also discuss quasi-elastic light scattering (QELS),
cryogenic transmission electron microscopy (cryo-TEM) and turbidity (optical density)
measurements of Quatsomes.
Figure caption: Illustration of a Quatsome. Left: scheme showing the bimolecular assembly formed by a CTAB
surfactant and a cholesterol molecule. The colored areas illustrate the shapes of the individual molecules (note
that the global bimolecular self-assembled entity has a shape appropriate for vesicular self-assembly). Center:
Cryo-TEM image of Quatsomes, an scheme of the supramolecular organization is also shown (right).
[1] Ferrer-Tasies, L.; Moreno-Calvo, E.; Cano-Sarabia, M.; Aguilella-Arzo, M.; Angelova, A.; Lesieur, S.;
Ricart, S.; Faraudo, J.; Ventosa, N.; Veciana, J., Langmuir (Submited).
112
O6.6
Internal and free energy in a pair of like-charged colloids. Confined and bulk
fluids
Alejandro Cuetos1,*, Juan A. Anta1 and Antonio Puertas2
1
Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013
Seville, Spain.
2
Departamento de Física Aplicada, University of Almería, 04120 Almería, Spain
*[email protected]
The effective interaction between two colloidal particles in a bath of monovalent coand counterions is studied by means of lattice Monte Carlo simulations with the primitive
model. The internal electrostatic energy as a function of the colloid distance is studied fixing
the position of the colloids. The free energy of the whole system is obtained introducing a bias
parabolic potential, that allows us to sample efficiently small separations between the colloidal
particles. This method has been applied to confined and non-confined situations. In the nonconfined case, for small charges,both the internal and free energy increase when the colloids
approach each other, resulting in an effective repulsion driven by the electrostatic repulsion.
When the colloidal charge is large enough, on the other hand, the colloid-ion coupling is
strong enough to form double layers. The internal energy in this case decreases upon
approaching the colloids because more ions enter the double layer. This attractive contribution
to the interaction between the colloids is stronger for larger charges and larger ionic
concentrations. However, the total free energy increases due to the loss of ionic entropy, and
resulting finally in a repulsive interaction potential driven by the entropic contributions. For
fluids with strong confinement in one of the dimensions of the simulations box, similar results
have been found. Although there are numerical differences with the bulk case, the qualitative
behavior is basically the same. In the range of charge studied and in a bath of monovalent
ions, attraction between like charged colloids has not been found. The overall behavior is
captured by the DLVO theory qualitatively, and a comparison is made with the functional
form predicted by the theory, showing moderate agreement.
BIOTECHNOLOGICAL APPLICATIONS
113
O7.1
Multiplexed Plasmon Sensor for Rapid Label-free Analyte Detection
Rubén Ahijado-Guzmán1, Christina Rosman1, Janak Prasad1,2, Andreas Neiser1,
Andreas Henkel1, Jonathan Edgar1, and Carsten Sönnichsen1,*
1
Institute of Physical Chemistry, University of Mainz, Duesbergweg 10-14, D-55128 Mainz
2
Graduate School Materials Science in Mainz, Staudingerweg 9, D-55128 Mainz
*
[email protected]
Here we present a new experimental method for the detection (qualitative and
quantitative) of multiple analytes simultaneously
in complex biological samples by using
randomly deposited gold nanorods in a
microfluidic flow cell. Through the use of four
distinct proteins as targets, we demonstrate the
feasibility of the concept. Our technique has the
potential to simplify multiplexed detection and
reduce the costs of each sensor to negligible
dimensions. Using our engineered gold nanorods
as a plasmonic nanosensor, only a few
microliters of sample are needed for the fast
detection with the detection limit down to 1
nanomolar. In addition, we show the reusability
our sensors for multiple assays. Our technique
can also be potentially upscaled for detection of
several hundreds of analytes, which makes it
ideal platform for rapid detection of some kinds
of low abundant proteins at a fairly reasonable
cost.
Figure caption: Sensor fabrication strategy and detection method. a, To fabricate a mapped or position
encoded sensor, aptamer coated nanoparticles 1…i were deposited consecutively (recording their
positions after each step) in a microfluidic flow cell. b, an unmapped sensor is produced by mixing all
particles 1…i before deposition. Hence, position encoding is not available. c, To detect an analyte in a
solution, it is injected into the flow cell (in both cases), the targets bind specifically to their
corresponding aptamer coated nanoparticles and induce shifts 'Ores in their plasmon resonances.
Acknowledgements: This work was financially supported by the ERC grant 259640 (“SingleSense”). J.
P. was financially supported by the graduate school of excellence Materials Science in Mainz.
114
O7.2
Development of DODAB:MO Liposomes for Gene Delivery
J. P. Neves Silva1, A. C. N. Oliveira2, A. F. C. Gomes2 and M. E. C. D. Real Oliveira1,*
1
CFUM (Centre of Physics of the University of Minho), Department of Physics, University of Minho,
Campus of Gualtar, 4710-057 Braga, Portugal.
2
CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho,
Campus of Gualtar, 4710-057 Braga, Portugal.
*
[email protected]
The artificial introduction of nucleic acids (NA) into mammalian cells (transfection) has
become, in recent years, a well-established procedure in basic and applied research, which allowed
the study of gene function and regulation [1]. The advances in this area have made possible the use
of these methods for gene-based medicines, which constitute alternative therapeutic approaches.
One of the most prominent methods is lipofection that uses cationic liposome/NA complexes (a.k.a.
lipoplexes) for the complexation, transport and release of therapeutic sequences into target cells.
Although yielding lower transfection efficiencies compared with viral gene delivery, lipofection
vectors have been chosen for medical applications due to their low mutational or toxicological risk.
Dioctadecyldimethylammonium Bromide (DODAB)/Monoolein (MO) liposomes have
recently been described as a new promising alternative to common transfection reagents, due to the
pioneering application of MO as helper lipid in lipoplex formulations. MO is not only responsible
for the fluidification of DODAB’s gel lamellar phase at physiological temperature, but also for the
formation on inverted bicontinuous cubic structures at MO’s molar fractions above 0.5 [2]. This
behavior, which was already reported in the absence of NA [2], becomes essential to modulate and
optimize
pDNA/DODAB/MO
physicochemical
properties
for
optimal in vivo application [1]. Indeed,
variation of lipoplex properties have
shown to affect the interaction with
different extracellular components and
their cell uptake and trafficking [1,3].
The
biocompatibility
of
pDNA/DODAB/MO lipoplexes has
also been reported to increase with
MO presence in the formulation,
supporting the use of this surfactant as
new helper lipid in lipofection [1,2,3].
Figure caption: Schematical phase diagram of structural organization pDNA/DODAB:MO lipoplexes.
Acknowledgements: FCT for funding through PTDC/QUI/69795/2006, SFRH/BD/46968/2008, PEstC/BIA/UI4050/2011 (CBMA) and PEst-C/FIS/UI0607/2011 (CFUM) projects. FEDER for funding through
POFC – COMPETE.
[1] Silva, J. P. N., A. C. N. Oliveira, A. C. Gomes, and M. E. C. D. R. Oliveira, Development of DODAB-MO
Liposomes for Gene Delivery. In Cell Interaction; S. Gowder, Editions InTech, Rijeka (Croatia), 2012,
pp. 245-272.
[2] Oliveira, I. M. S. C., J. P. N. Silva, E. Feitosa, E. F. Marques, E. M. S. Castanheira, and M. E. C. D. R.
Oliveira, J. Colloid Interface Sci. 2012, 374, 206-217.
[3] Silva, J. P. N., A. C. N. Oliveira, M. P. P. A. Casal, A. F. C. Gomes, P. J. G. Coutinho, O. M. F. P.
Coutinho, and M. E. C. D. R. Oliveira, Biochim. Biophys. Acta 2011, 1808, 2440-2449.
115
O7.3
Using AFM to study the complexation of DNA and anionic lipid mediated by
Ca2+ at the air-water interface
Germán Luque-Caballero*, Alberto Martín-Molina and Julia Maldonado-Valderrama
Applied Physics Department. Campus de Fuentenueva sn, 18071. University of Granada, Spain.
*
[email protected]
Langmuir monolayers constitute at present a novel approach to study interaction
between lipids and DNA mimicking interactions in membranes with biotechnological
applications. Particularly, we have studied the DNA binding to negatively charged
phospholipid monolayers mediated by Ca2+ evaluating interfacial adsorption and aggregation
phenomena at the air/water interface. To this end, we tracked the changes in the surface
pressure-area isotherms induced by the presence of both Ca2+ and DNA in the subphase which
is displaced to higher areas at low surface coverage. Gibbs elasticity of these monolayers
shows also a dramatic decrease caused by the complexation with DNA in the presence of Ca2+
and suggests additional rearrangements occurring in the monolayer. Finally, LangmuirBlodgett transfer to solid supports enables visualization of the system by means of atomic
force microscopy (AFM). As a result we demonstrate that the presence of DNA in the
monolayer affects drastically the mesostructure forming interfacial aggregates whose size and
morphology can be modulated by the surface pressure. The results presented here offer a new
perspective into the characterization of anionic lipoplexes by the use of LB-AFM to follow the
interfacial aggregation process and to characterize the morphologies of the different
aggregates observed. These results can contribute to improve the function and stability of lipid
vectors for gene therapy purposes.
Figure caption: A) DPPC/DPPS 4 :1 surface pressure-area isotherms. B) AFM images of
phospholipid/Ca2+/DNA interfacial aggregates in a Langmuir-Blodgett monolayer transferred
at = 25 mN/m.
Acknowledgements: This work has been sponsored by Junta de Andalucía-P09-FQM-4698. Other
projects are acknowldeged: EU-FP7-PERG07-GA-2010-268315-ColloDi, JCI-2009-03823, MAT201020370 and CEI-Biotic 20F12/16 and Microproyecto2013 (UGR).
[1] Luque-Caballero, G.; Martín-Molina, A.; Sánchez-Treviño, A. Y.; Rodríguez-Valverde, M. A.;
Cabrerizo-Vílchez, M. A.; Maldonado-Valderrama, J. Submitted.
116
O7.4
Gene Transfer Mediated by Bis-Quaternary Gemini Surfactants Depends on
Complex Architecture
A. M. Cardoso1,*, C. M. Morais1, S. G. Silva2, M. L. do Vale2, E. Marques2,
M. C. Pedroso de Lima1,3 and A. S. Jurado1,3
1
CNC - Centre for Neuroscience and Cell Biology, University of Coimbra, Portugal
Centro de Investigação em Química, Department of Chemistry and Biochemistry, University of Porto,
Portugal
3
Department of Life Sciences, University of Coimbra, Portugal
*
[email protected]
2
The conformational flexibility provided by the spacer and by the double hydrocarbon
chains to cationic gemini surfactants has been shown to confer them properties of successful nonviral gene delivery systems, with low toxicity and high nucleic acid protection ability. In this work,
a
family
of
gemini
surfactants,
represented
by
the
general
structure
[CmH2m+1(CH3)2N+(CH2)sN+(CH3)2CmH2m+1]2Br, was used to prepare cationic gene carriers. An
exhaustive study on the transfection efficiency and cytotoxicity mediated by the complexes formed
by each gemini surfactant, either per se or in combination with helper lipids (cholesterol and
DOPE), was performed, and their ability to protect the cargo was determined. A physico-chemical
characterization of the complexes was addressed to evaluate which properties would be responsible
for the vector performance. Large (>3 μm) complexes revealed the highest efficiency to deliver
plasmid DNA to HeLa cells, regardless of their surface charge. The occurrence of a phase
transition in gemini surfactant dispersions close to physiological temperature and the presence of
structural irregularities in surfactant/DNA complexes showed to be correlated with transfection
efficiency. On the other hand, only complexes highly fluid at 37ºC exerted high cytotoxicity. Our
proposal is that the structural architecture of the complexes guides their membrane interactions and
the nature and extent of these interactions underlie the biological activities of the complexes [1].
Therefore, a biophysical study of DNA vector architectural structure represents a step forward
towards the rational design of efficient gene delivery systems.
A.
B
Figure caption: The presence of a phase transition around 37 ºC in gemini surfactant dispersions (A) correlates with the
transfection efficiency of the corresponding DNA complexes (B).
Acknowledgements: The authors acknowledge Prof. G. Rasteiro, University of Coimbra, for the opportunity to use
the zeta sizer device. This work was supported by the grants PTDC/QUI-BIQ/103001/2008, PTDC/DTPFTO/0265/2012 and PEst-C/SAU/LA0001/2011 funded by FCT and FEDER/COMPETE. A.M.C., C.M.M and S.G.S.
are recipients of fellowships from the FCT (SFRH/BD/63288/2009, SFRH/BD/79077/2011 and
SFRH/BD/61193/2009, respectively).
[1] Cardoso, A. M. S. et al., Biochim. Biophys. Acta, 2012, 1818, 877–88.
POSTERS SPECIAL SESSIONS
119
PSS01
Luminiscent/Magnetic Liposomes with RGD-conjugate peptide for theranostic
applications
M. A. Busquets1,2,*, E. Escribano2,3, J. Queralt2,4, M. Sangrà1, M. Gallardo1,2, and J. Estelrich1,2
1
Departament de Fisicoquímica. 2Departament de Farmàcia i Tecnologia Farmacèutica.
Departament de Fisiologia Humana. Facultat de Farmàcia. Universitat de Barcelona. Avda Joan
XXIII, s/n. 08028 Barcelona.
4
Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, C/ Martí i Franquès 1,
08028 Barcelona.
*
[email protected]
3
Theranostic nanoparticles have gained increased attention in the last decade because
of their potential application in both therapy and diagnosis [1]. Among these particles,
magnetoliposomes (MLs) are of particular interest due, in addition, to their lack of toxicity
and biodegradability [2]. Bearing in mind the utility of these nanostructures, we have
developed a kind of liposomes loading a biocompatible ferrofluid [3, 4] and bearing on the
surface a fluorescent probe and polyethylene glycol (PEG) to assure the biological stability.
Some of the terminal ends of the PEG chains were derivatized with the tripeptide RGD. The
RGD sequence is known to serve as a recognition motiv for some antigens over-expressed on
tumor cells surface and on activated platelets. Finally, a drug can be encapsulated in the
aqueous inner (if hydrophilic) or inserted in the bilayer (if hydrophobic), and the theranostic
system is completed (Figure 1). Depending on the applications to perform, the system can be
modified. We have determined
the physichochemical properties
of
the
nanoparticles
(hydrodynamic
diameter,
potential
and
magnetization
among others) and we have
observed their uptake by cells
visualized by fluorescent signal.
On another hand, we have
checked the pharmacological
effect in inflammation model in
vivo studies. Finally, we have
demonstrated the application of
the nanoparticles as magnetic
resonance
imaging
contrast
agents.
Figure caption: Multifunctional magnetoliposomes.
Acknowledgements: This work was supported by the grant MAT2012-36270-C04-03 from the Spanish
Ministerio de Economía y Competitividad.
[1] Janib, S. M.; Moses, A. S.; MacKay, J. A. Adv. Drug Deliv. Res. 2010, 62, 1052-1063.
[2] Soenen, S. J.; Hodenius, M.; De Cuyper, M. Nanomedicine 2009, 4, 177-191.
[3] García-Jimeno, S.; Escribano, E.; Queralt, J.; Estelrich, J. Int J Pharm 2011, 405, 181-187.
[4] García-Jimeno, S.; Estelrich, J. Coll Surf A 2013, 420, 74-81.
120
PSS02
Interfacial activity comparison between bare, homogeneous and Janus gold
nanoparticles
M. A. Fernandez-Rodriguez1,*, M. A. Rodriguez-Valverde1, M. A. Cabrerizo-Vilchez1,
Y. Song2, S. Chen2, A. Sánchez-Iglesias3, L. Liz-Marzán3 and R. Hidalgo-Alvarez1
1
Biocolloid and Fluid Physics Group, Applied Physics Dept., Faculty of Sciences, University of
Granada, 18071 Granada (Spain).
2
Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, CA
95064 (USA).
3
CIC biomaGUNE, 20009 San Sebastián (Spain).
*
[email protected]
The interfacial activity of gold nanoparticles can be modified with the use of capping
ligands. The interfacial activity was characterized for bare gold nanoparticles (3 nm diameter),
hexanethiol-functionalized gold nanoparticles (2 nm-core diameter) and Janus gold
nanoparticles (2 nm-core diameter) composed of two regions of different hydrophilic
character: hexanethiol and 2-(2-mercapto-ethoxy)ethanol) [1,2]. THF was used as an
extension agent and the compression isotherms of each studied nanoparticle at the water-air
and water-decane interfaces were performed using the pendant drop technique [3] for different
particle concentrations (Fig. 1). The particles were aggregated at the water-air and waterdecane interfaces in sizes of hundreds of nanometers up to micrometers.
Figure caption: Water-decane interfaces with 1.66·1012 (left) and 33·1012 (right) Janus gold nanoparticles
deposited at the interface.
Acknowledgements: This study was supported by the ``Ministry of Science and Innovation'' (project
MAT2011-23339) by the ``Junta de Andalucía'' (projects P08-FQM-4325 and P10-FQM-5977), and by
US National Science Foundation (DMR-0804049). Authors thank to Dr. J.A. Holgado-Terriza,
programmer of the software Dinaten used for surface tension measurements.
[1] Pradhan S.; Xu L.; and Chen S., Janus nanoparticles by interfacial engineering, Adv. Funct. Mater.
2007, 17, 2385-2392.
[2] Pradhan S.; Brown L.; Konopelski J.; and Chen S., Janus nanoparticles: reaction dynamics and noesy
characterization, J. Nanopart. Res. 2009, 11, 1895-1903.
[3] Torcello-Gómez A.; Maldonado-Valderrama J.; Gálvez-Ruiz M. J.; Martín-Rodríguez A.; CabrerizoVílchez M. A.; Vicente J., Surface rheology of sorbitan tristearate and -lactoglobulin: Shear and
dilatational behavior, J. Non-Newton Fluid 2011, 166, 713-722.
121
PSS03
Growth of metal sulfides on polymer beads: a starting point for nanocapsules
Márcia C. Neves1,*, Mariana M. Silva1, Diogo Lopes1, Tito Trindade1
1
CICECO and Chemistry Department, University of Aveiro, 3810-193 Aveiro, Portugal
*
[email protected]
The preparation of hollow inorganic capsules of defined shape, composition and with
tailored properties is of great scientific and technological interest. Inorganic hollow capsules
have a void that can act as storage space to encapsulate various substances. These materials
have great impact in various technologies, including the encapsulation and controlled release
of drugs.
As an extension of the single source route to produce nanomaterials,[1] we have
developed a technique to perform nanocoatings of metal chalcogenides on diverse types of
inorganic substrates.[2,3] In this method, metal alkyldithiocarbamate complexes are used as
single-molecule precursors and at mild temperatures, in order to modify in situ the surface of
substrates by the respective metal chalcogenide. Here, we communicate our results on the
adaptation of this method to the use of synthetic polymer beads as substrates for the
attainment of polymer/metal sulfide nanocomposites and in which the polymer can be used as
a sacrificial template. Therefore these composite structures were investigated as precursors to
produce hollow capsules that carry an organic dye, regarded as a drug model, whose release
behavior was monitored in diverse experimental conditions.
Acknowledgements: M.C. Neves thanks Fundação para a Ciência e Tecnologia (FCT) for the grant
SFRH/BPD/35046/2007. The authors acknowledge FCT (Pest-C/CTM/LA0011/2011), FSE and POPH
for funding.
[1] Trindade, T.; O’Brien, P., Adv. Mater., 1996, 8, 161-163.
[2] Monteiro O.C.; Esteves, A.C.C.; Trindade, T.; Chem. Mater. 2002, 14, 2900-2904
[3] Neves, M. C.; Monteiro, O. C.; Hempelmann, R.; Silva, A. M. S.; Trindade, T.; Eur. J. Inorg. Chem.,
2008, 4380-4386
122
PSS04
Synthesis and modification of metal nanoparticles in organic medium for
plasmonic applications
Lakshminarayana Polavarapu1,*, and Luis M. Liz-Marzán1,2,3
1
BioNanoPlasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia, Spain
2
3
Departamento de Química Física, Universidade de Vigo, 36310 Vigo, Spain.
*
[email protected]
Metal nanoparticles, in particular gold and silver nanoparticles have received
significant attention in nanotechnology research because of their ability to manipulate the
light1 by means of strong surface plasmon resonances, which makes them suitable candidates
for enhanced optical sensing of chemical and biological species for detection, diagnosis,
plasma enhanced solar cells and catalysis.[1,2] The plasmonic properties of Au and Ag NPs
strongly depend on their size and shape [3] and therefore controlling the morphology and
monodispersity of NPs is very important for practical applications. Although significant
progress has been made in the synthesis of metal NPs in polar organic solvents, little has been
advanced toward shape-controlled synthesis in non-polar solvents. The preparation of NPs in
organic medium has several advantages such as monodispersity, large scale synthesis, organic
catalysis and many more. In this communication, we present an overview of the synthesis of
plasmonic NPs of different shapes in organic medium. We present in particular our recent
results on the simple synthesis of nearly monodisperse single crystalline Ag nanocubes in
organic medium by using oleylamine as both reducing and capping agent [4]. Mechanistic
studies based on the time dependent evolution of Ag NPs revealed that oxidative etching of
multiply twinned Ag NPs that formed in the initial stages resulted in single crystalline Ag
nanocubes. We have further demonstrated the galvanic replacement reaction with HAuCl4 in
organic medium to prepare hydrophobic hollow Au-Ag nanocages with tunable localized
surface plasmon resonances. The SERS enhancing properties of such nanocages will be
presented.
Metal NPs prepared in organic medium: (a) Ag nanoparticles, (b) Ag nanocubes, (c) Ag-Au nanocages.
Acknowledgements: Funding is acknowledged from the European Research Council through the
Advanced Grant #267867 (PLASMAQUO).
[1] Alvarez-Puebla, R. A.; Liz-Marzán, L. M.; García de Abajo, F. J. J. Phys. Chem. Lett. 2010, 1, 2428.
[2] Polavarapu, L.; Liz-Marzán, L. M. Phys. Chem. Chem. Phys. 2013. 15, 5288.
[3] Cao, Y. W. C.; Jin, R. C.; Mirkin, C. A. Science 2002, 297, 1536.
[4] Polavarapu, L.; Liz-Marzan, L. M. Nanoscale 2013. DOI: 10.1039/C3NR01244A.
123
PSS05
Metallic Janus particles
D. Rodríguez-Fernández1,2,*, J. Pérez-Juste2, I. Pastoriza-Santos2, and L. M. Liz-Marzán1,2,3
1
Center for Cooperative Research in Biomaterials (CIC BiomaGUNE), Paseo de Miramón 182, 20009,
San Sebastián, Spain.
2
Departamento de Química Física, Universidad de Vigo, 36310 Vigo, Spain.
3
Ikerbaske, Basque Foundation for Science, 48011 Bilbao, Spain
*
[email protected]
The fabrication of particles with multiple surface compositions and functionalities or
patchy particles has become a hot topic due to their interesting properties and potential
applications in a wide variety of fields. Janus particles belong to a special type of patchy
particles that exhibit only one patch that covers half of a sphere. The use of a metallic
component provides these particles with new properties making them interesting for
applications in catalysis, optical imaging or surface enhanced Raman scattering (SERS)
spectroscopy, among others.[1]
In this communication we describe the main synthetic approaches to obtain metallic
Janus particles, their properties and applications. We focus on asymmetric particles with a
gold patch such as semishells, semicapsules or Janus stars, interesting from the optical point of
view, due to the presence of localized surface plasmon resonances.[2]
Acknowledgements: This work was funded by the European Commission FP7 project Nanodirect (No.
CP-213948) and the European Research Council Advanced Grant PLASMAQUO (No. 267867). D.R.-F.
acknowledges the Spanish Miniserio de Educación Cultura y Deporte for an F.P.U. scholarship.
[1] Rodríguez-Fernández, D.; Liz-Marzán, L. M.; Part. Part. Syst. Charact. 2013, 30, 46–60
[2] Rodríguez-Fernández, D.; Pérez-Juste, J.; Pastoriza-Santos, I.; Liz-Marzán, L. M.; ChemistryOpen
2012, 1, 90–95
124
PSS06
Oil-in-Water microemulsions for the synthesis of CeO2, CuO, and CuO/CeO2
nanoparticles and their use as photocatalysts
Margarita Sánchez-Domínguez1,*, Andrea V. Vela-Gonzalez1, Kelly Pemartin2, Conxita
Solans2, Sergio A. Pérez-García1, César C. Leyva-Porras1 and Isaías Juárez-Ramírez3
1
Centro de Investigación en Materiales Avanzados (CIMAV), Unidad Monterrey, GENES-Group of
Embedded Nanomaterials for Energy Scavenging, Alianza Norte 202, Parque de Investigación e
Innovación Tecnológica, 66600 Apodaca, N.L., México.
2
Instituto de Química Avanzada de Cataluña, Consejo Superior de Investigaciones Científicas (IQACCSIC) and CIBER en Biotecnología, Biomateriales y Nanomedicina (CIBER-BBN), Jordi Girona 18-26,
08034 Barcelona, Spain.
3
Departamento de Ecomateriales y Energía, Instituto de Ingeniería Civil, Facultad de Ingeniería Civil,
Universidad Autónoma de Nuevo León, Cd. Universitaria, 66451 San Nicolás de los Garza, N.L. México
*
[email protected]
Introducing different metals into CeO2 affects its characteristics, and in particular the
oxygen vacancies, which in turn determine some of its properties such as oxygen storage
capacities, which are important for several applications. A method based on oil-in-water
(O/W) microemulsions as confined reaction media was recently developed for the preparation
of metallic and metal oxide nanoparticles [1, 2]. The advantage of this new approach is the use
of water as a continuous phase, more environmentally friendly than organic solvents generally
used in the traditional water-in-oil (W/O) microemulsion method. In this study, the synthesis
of a hybrid oxide material based on Cerium (Ce) and Copper (Cu) using the O/W
microemulsion reaction method has been explored; the pure oxides (CeO2 and CuO) were
synthesized and characterized as well for comparison purposes. The nanoparticles were
characterized by X-Ray Diffraction (XRD), High Resolution Transmission Electron
Microscopy (HRTEM), Scanning Electron Microscopy (SEM), BET, TGA/DSC, XPS and
diffuse reflectance spectroscopy. Cu/Ce molar ratio from 5/95 to 30/70, resulted in mixed
Cu/Ce oxide in which Cu appear to be either incorporated in the crystal structure of cubic
CeO2, or very well dispersed. At Cu/Ce molar ratio (50/50), an excess CuO phase was also
obtained. The bandgap of the materials was determined as a function of copper content and it
was found that it decreased as Cu content increased. Although the use of individual materials
CeO2 and CuO as photocatalysts has been reported in the literature, and mixed CeO2/CuO
materials have been synthesized by several methods and used as catalysts in reactions such as
the Water Gas Shift, this mixed oxide has not been evaluated as photocatalyst. Therefore, and
given the dependence of the bandgap on the composition of the mixed oxide, the synthesized
materials were evaluated as photocatalysts for the degradation of an organic dye as model
contaminant.
Acknowledgements: We are grateful to CONACYT for financial support (CB project No. 166649 and
Proyecto de Redes Temáticas No. 194451). We also acknowledge Josué A. Aguilar, Alberto Toxqui and
Nayeli Pineda (CIMAV, S.C.) for their technical assistance.
[1] Sánchez-Domínguez, M.; Boutonnet, M.; Solans, C. J. Nanoparticle Research 2009, 11, 1823-1827
[2] Sánchez-Domínguez, M.; Pemartin, K.; Boutonnet, M. Curr. Opin. Colloid Interface Sci. 2012, 17,
297-305.
125
PSS07
Preparation of organic solvent resistant nanocarriers from O/W nano-emulsions
as templates
Silvia Vílchez-Maldonado, Ricardo Molina, Jordi Esquena and Gabriela Calderó*
Instituto de Química Avanzada de Cataluña (IQAC), Consejo Superior de Investigaciones Científicas
(CSIC). Jordi Girona 18-26, 08034 Barcelona, (Spain) and Centro de Investigación Biomédica en Red
en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN)
*
[email protected]
The study of nanoparticles has experienced a significant increase due to their wide
application fields and the new developments in several areas such as medicine, biotechnology,
engineering, etc. A well-known method to prepare nanoparticles is the use of nano-emulsions
as templates and subsequent solvent evaporation [1]. Among the nano-emulsion preparation
methods, the low energy emulsification methods are of special interest due to the energy
savings that they involve [2]. The main objective of this work is the preparation of
nanocarriers, resistant to organic solvents, using oil in water (O/W) nano-emulsions as
templates. For this purpose, the influence of the incorporation of a sunscreen (2-Ethylhexyl 4dimethylaminobenzoate) and/or a crosslinking agent (hexamethylene diisocyanate) in the oil
phase of a model O/W nano-emulsion, obtained in a previously studied water/Solutol
HS15/(7% ethylcellulose in ethyl acetate) system at 25ºC [3], was investigated. The
oil/surfactant ratio of the model nano-emulsion was 70/30 and the water content 90wt%. It
was found that the incorporation of the sunscreen and crosslinking agents do not produce
significant changes in droplet size (hydrodynamic diameter around 180 nm), surface charge
(about -20 mV) and nano-emulsion stability, as revealed by dynamic light scattering (DLS),
Zeta potential and light backscattering measurements. The nanoparticle dispersions were
obtained from the nano-emulsions by the solvent evaporation method and showed similar
features, concerning surface charge and stability, to the template nano-emulsions. As
expected, the nanoparticle sizes (around 50-60 nm, as observed by TEM) were much smaller
than the template nano-emulsions. Moreover, the results revealed that despite of the addition
of the sunscreen and the crosslinking agent, the shape and size of the nanoparticles did not
show remarkable changes. The nanoparticle analysis by high performance liquid
chromatography (HPLC) evidenced that the sunscreen agent was successfully incorporated
into the nanoparticles. Further, nanoparticles containing diisocyanate were heated at a
temperature of 50 ºC during 24 hours to trigger the crosslinking reaction. The resistance of
these nanoparticles to organic solvents was assessed by nanoparticle size measurements as a
function of time in mixtures of nanoparticle dispersions with ethanol at different ratios. The
data obtained indicate that the ethylcellulose nanoparticles, which are soluble in ethanol, were
resistant to this solvent after crosslinking with hexamethylene diisocyanate at any nanoparticle
dispersion/EtOH ratio. These results confirm that the selected O/W nano-emulsion is an
appropriate template to prepare polymeric nanocarriers and that crosslinking of the
nanoparticles endows them with organic solvent resistant features.
[1] Desgoullies, S. et al. Langmuir, 2003, 19, 9504-9510.
[2] Solans, C., Solé, I. Opin. Colloid Interface Sci., 2012, 17, 246–254.
[3] Calderó, G. García-Celma, M. J. and Solans, C. J. Colloid Interface Sci., 2011, 353, 406-411.
126
PSS08
Interaction between a zwitterionic thiophene based conjugated polyelectrolyte
and surfactants in aqueous solution
Telma Costa1,*, Diego de Azevedo1, Matti Knaapila,2 Artur Valente1, Mario Kraft3,
Ullrich Scherf3 and Hugh D. Burrows1
1
Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-535
Coimbra, Portugal.
2
Physics Department, Institute for Energy Technology, P.O. Box 40, 2027 Kjeller, Norway
3
Makromolekulare Chemie, Bergische Universität Wuppertal, D-42097 Wuppertal, Germany.
*
[email protected]
Conjugated polyelectrolytes (CPEs) are advanced materials, which find use in a
broad range of applications, such as chemical and biological sensing, charge injection or
transport layers, light emitting devices, photovoltaic systems and two photon absorbers.[1]
Here, we present the photophysical characterization of a zwitterionic water-soluble
polythiophene derivative (P3DEBAHT) in aqueous and in dioxane:water solutions.
Zwitterionic CPEs in which the conjugated polymers carry both positively and negatively
charged groups can avoid the problem of counter-ions adversely affecting optoelectronic or
other properties.[2, 3]
Additionally, the interaction between P3DEBAHT polyelectrolyte and different
surfactants was studied using absorption, fluorescence, conductivity and small-angle X-ray
scattering (SAXS). The formation of CPE/surfactant complexes is extremely important in
terms of modulation of CPE properties and development of new Förster resonance energy
transfer systems for sensing or light harvesting. Cationic, anionic and zwitterionic surfactants
were able to modulate the photophysical properties of the P3DEBAHT. Above their critical
micelle concentration, the CPE displays an increase in its fluorescence quantum yield and a
blue shift of the maximum emission wavelength. In contrast, the presence of pentaethylene
glycol monododecyl ether, a nonionic surfactant, and the water soluble poly(vinyl alcohol) did
not have any effect on P3DEBAHT emission properties. This fact emphasizes the importance
of electrostatic interactions on the self-assembly between zwitterionic CPE and surfactants.
Conductivity and SAXS measurements were also performed to follow changes in the ionic
part of the system and characterize the size and the shape of the self-assemble structures
formed.
Acknowledgements: The authors thank FCT, the Portuguese agency for scientific research, which has
supported this work through a Postdoctoral Grant to TC (SFRH/BPD/47181/2008). The research leading
to the SAXS data has received funding from the European Community's Seventh Framework Programme
(FP7/2007-2013) CALIPSO under grant agreement nº 312284.
[1] Liu, B.; Bazan, G. C. Conjugated Polyelectrolytes. Fundamentals and Applications in Emerging
Technologies, Wiley-VCH: Weinheim, 2013.
[2] Fang, J., Wallikewitz, B. H.; Gao, F.; Tu, G.; Müller, C.; Pace, G.; Friend, R. H.; Huck, W. T. S., J.
Am. Chem. Soc. 2011, 133, 683-685.
[3] Scherf, U., U. Angew. Chem. Int. Ed. 2011, 50, 5016–5017.
127
PSS09
Ionization by pH and anionic surfactant binding gives the same thickening
effects of crosslinked polyacrylic acid derivatives
Cláudia M. G. Duarte1,*, Luís Alves1, Filipe E. Antunes1,*, Björn Lindman1, Björn Klotz2,
Axel Böttcher2 & Hans-Martin Haake2
2
1
Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
BASF Personal Care and Nutrition GmbH, 40589 Duesseldorf, Germany
*[email protected]
Physical properties of aqueous solutions of hydrophobically modified cross-linked
polyacrylates change quite extensively, as the polymer is charged up. A study is carried out
concerning the similarities between two polymer ionization processes, i. e. by pH increment
and anionic surfactant addition. The two processes charge the polymer by distinctly different
mechanisms. At sufficiently high pH the carboxylic groups of the polymer are all virtually
ionized and the polymer is, therefore, fully charged. The effective repulsion among the
charged groups due to the entropy of the counterions promotes an increased stiffness as well
as an expansion of the polymer particle. We investigate here how the ionization and swelling
will be if, instead of high pH, the polymer is placed at low pH conditions but associated to
ionic surfactants. Surfactants associate to the polymer both in a non-cooperative way by the
binding of individual surfactant molecules and in a cooperative way as micelles since the
polymer promotes surfactant self-assembly. This binding leads to a highly charged polymersurfactant complex and leads to an osmotic swelling as well. The swelling and the gelation
were monitored by rheology and dynamic light scattering, of polymer solutions at different
pH’s and by adding ionic surfactants at low pH. The results show that ionization by
surfactants and by pH lead to approximately the same gelation degree, as can be seen by
similar viscosity values. Both processes result in dramatic viscosity increases, up to 8 orders
of magnitude. More hydrophobic surfactants, with longer alkyl chain, are shown to be more
efficient as enhancers of swelling and gelation. The network that is formed at high pH or at
sufficiently high concentration of surfactant can be weakened or even disrupted if monovalent
or divalent salts are added, demonstrating the role of counterion entropy.
128
PSS10
The influence of the combination of Fe(III) ions with BPEI and LPEI in DNA
condensation: Physico-chemical characterization and in vitro cytotoxicity testing
A. F. Jorge1,*, M. C Morán2, M. P. Vinardell2, R. S. Dias1 and A. A. C. C. Pais1
1
2
Department of Chemistry, University of Coimbra, 3004-535 Coimbra
Department of Physiology, University of Barcelona, 08028 Barcelona, Spain
*
[email protected]
Eƥcient DNA condensation, as well as low toxicity, is required for an eƥcient gene
delivery vehicle. To this end, we combined polyethylenimine (PEI) and Fe (III) ions probing
different charge ratios N/P and Fe(III)/P. Fe(III) proved to enhance the DNA condensation and
also decondensation when combined with PEI 1. In the present work, LPEI (2.5 and 25 kDa)
and BPEI (1.2 and 10 kDa) were used in conjunction with Fe(III) to investigate the influence
of the architecture and charge of the polycation on the ternary system. The degree of binding
(UV and agarose gel electrophoresis), size and zeta potential were measured. Also,
cytotoxicity and hemolysis studies were conducted to evaluate the influence of PEIs and
Fe(III) ions, alone and complexed with DNA, on 3T3 and HeLa cells. The results show that, in
the absence of Fe(III) ions, the polycations present different abilities to condense DNA. The
addition of Fe(III) ions tend to equalize the charge ratios for DNA condensation, and a more
pronounced compaction enhancement is obtained with the polycations with a lower Mw. The
DNA-BPEI-Fe(III) system tends to form larger aggregates than DNA-LPEI-Fe(III), but at low
concentrations of Fe(III), DNA-PEI-Fe(III) determines similar or even smaller sizes than the
DNA-PEI counterparts. The addition of Fe(III) alters the zeta potential of the complexes from
ca. -30 mV at N/P 2.5 to +10 mV when Fe/P 7 is added. Finally, the impact of the substitution
of PEI chains by Fe (III) ions on cells was analyzed. The results show a decrease in the
cytotoxicity of the complexes with DNA-PEI-Fe(III), when compared to PEI-DNA complexes
in the same degree of compaction.
Acknowledgements: This work was supported by FEDER Funds through the COMPETE Program “
Programa Operacional Factores de Competitividade (FCOMP-01-0124-FEDER-010831) “ and by
National Funds through Fundação para a Ciência e Tecnologia (FCT) under Project: PTDC/QUIQUI/101442/2008. A. F. Jorge gratefully acknowledges the PhD grant SFRH / BD / 66748 / 2009
assigned by the Fundação para a Ciência e Tecnologia
[1] Jorge A.F.; Dias, R.S..; Pais A.C.C., Biomacromolecules 2012, 13, 3151-61.
129
PSS11
Characterization of Water/Sodium Dodecyl Sulphate/Propanol/Allylbenzene
Micellar Systems
Monzer Fanun*
Colloids and Surface Research Center, Al-Quds University, East Jerusalem 51000, Palestine
*
[email protected]
Water/n-propanol/sodium dodecyl sulphate/ allylbenzene micellar systems were
formulated. The ratio (w/w) of n-propanol/surfactant equals 2/1. The extent of the micellar
region as function of temperature was determined. The micellar systems were characterized by
the volumetric parameters, density, excess volume, ultrasonic velocity and isentropic
compressibility. The micellar densities increase with the increase in the water volume fraction.
Excess volumes of the sodium dodecyl sulphate decrease for water volume fraction below 0.3,
stabilize for water volume fractions between 0.2 and 0.5 then increase for water volume
fraction above 0.5. Excess volumes of the studied micellar systems increase with temperature.
Ultrasonic velocities increase with the increase in water volume fraction up to 0.8 then
decreases. Ultrasonic velocities increase with temperature for water volume fractions below
0.8 and increase for water volume fractions above 0.8. Isentropic compressibilities decrease
with the water volume fraction up to 0.8 then increases. Isentropic compressibilities increase
with temperature for water volume fractions below 0.8 and decrease for water volume
fractions above 0.8. Structural transitions from water-in-oil to bicontineous to oil-in-water
occur along the micellar phase. The particle hydrodynamic diameter of the oil-in-water
micellar systems was found to decrease with temperature. In the diluted region nanoemulsion
systems were observed. The results presented in this study recommend performing
allylbenzene isomerization reactions at water volume fractions above 0.95 or at surfactant
contents slightly above the critical micelle concentration and at high temperatures
130
PSS12
Influence of humic acids as colloidal systems on the stability of xenobiotics
J. C. Mejuto1,*, J. Morales1, O. Moldes1, J. A. Manso2
1
Physical Chemistry Department, University of Vigo, 32004 Ourense, Spain.
2
Cancer Research Center, 37007 Salamanca, Spain.
*
[email protected]
In solution, humic substances can form complexes with environmental pollutants [13]. It is well known their nature as colloids and their behaviour in solution is quite similar to
the micellar aggregates [4]. On the other hand, the pesticides carbofuran and carbofuranderivatives are widely used in agriculture as systemic insecticide with plenty of adverse
effects [5]. An inhibition of the alkaline hydrolysis of 3-hydroxy-carbofuran and 3-ketocarbofuran in the presence of colloidal aggregates derived of humic acids (one type of humic
substances) has been observed. The results were rationalized in terms of micellar pseudophase
model. These inhibitions represent an increase of half-life time of these xenobiotics. However,
non-significant effect upon the carbofuran stability in basic media was found in presence of
humic acids.
Figure caption: Pseudophase model upon the basic hydrolysis of carbofuran and carbofuran-derivatives
in humic aggregates.
Acknowledgements: The authors thank the Xunta de Galicia (10PXIB383187PR) for financial support.
Jorge Morales thanks the University of Vigo for a research-training grant (P.P. 0022 122I 641.03).
[1] LeBoeuf, E. J.; Weber Jr., W. J., Environ. Sci. Technol. 2000, 34, 3632–3640.
[2] Zhou, P.; Yan, H.; Gu, B., Chemosphere 2005, 58, 1327-1337.
[3] Prosen, H.; Zupancic-Kralj, L., Environ. Pollut. 2005 133, 517–529.
[4] Astray, G.; Garcia-Río, L.; Lodeiro, C.; Mejuto, J. C.; Moldes, O.; Morales, J.; Moyano F., Int. J.
Chem. Kinet. 2010, 42, 316-322.
[5] Krol, J.; Romano, J.; Block, E., Am. Chem. Soc., Div. Environ. Chem. 2001, 41, 649-656.
131
PSS13
Drug Delivery Systems based on diacyl arginine surfactants: preparation,
characterization and evaluation of their biological activity
L. Pérez1,*, L. Tavano1, M. R. Infante1, A. Pinazo1, M. A. Manresa2, M. P. Vinardell3,
M. Mitjans3
1
Department de Tecnologia Química i de Tensioactius, Institut de Química Avançada de Catalunya, CSIC.
Jordi Girona 18, 08034 Barcelona, Spain; 2Laboratori de Microbiologia, Facultat de Farmàcia,
Universitat de Barcelona. Av. Joan XIII s/n, 08028 Barcelona, Spain;3Departament de Fisiologia,
Facultat de Farmàcia, Universitat de Barcelona. Av. Joan XIII s/n, 08028 Barcelona, Spain
*[email protected]
In the last years our group has prepared new diacyl cationic surfactants based on the
amino acid arginine, with different structures (gemini, and glycerolipid), characterized by relevant
nontoxic and antimicrobial properties as well as rapid biodegradability. In addition, these
surfactants from arginine are extraordinarily active in reducing surface tension. Cationic colloidal
systems composed by these arginine based surfactants and membrane additive compounds have
been characterized by means of size distribution and zeta-potential measurements.
Gemini surfactants with the shortest spacer chain
(C6(LA)2) formed micelles, while aqueous solutions of pure
gemini surfactants with longer spacer (C9(LA)2 and C12(LA)2)
made up very big aggregates. The addition of phospholipids
or cholesterol changed drastically the aggregation behaviour.
In the case of C6(LA)2, the incorporation of additives gave
rise to the formation of cationic vesicles. For C9(LA)2 and
C12(LA)2, this type of additives promoted the formation of
smaller aggregates. We also evaluated the hemolysis and the
antimicrobial activity of these systems. The capability of
disrupting the erythrocyte’s membrane depends on the
hydrophobicity of the molecules and the size of aggregates in
the solution. The alkyl spacer chain and the presence of
additives also play an important role on the antimicrobial
activity, and, in general, the interaction with bacteria and
erythrocytes is affected by the same parameters.
Figure caption: Chemical structure of gemini (a) and glycerolipid (b) arginine-based surfactants.
The diacyl-glycerol arginine cationic lipids form stable cationic liposomes by themselves.
These cationic formulations can encapsulate two different drugs (Ciprofloxacine and 5-Fluorouracil
(5-FU)) and the percentage of encapsulated drug depends on the physicochemical properties of the
vesicles as well as on the type of drug. The capacity of the systems to vehiculate different
molecules was evaluated performing their in vitro drug release profiles. Cationic liposomes
without drug have antimicrobial activity and the activity of the encapsulated ciprofloxacine is
similar or higher to those of the free drug. These results suggest that our formulations represent a
great innovation in the pharmaceutical field, due to their dual pharmacological function: one related
to the nature of the vehiculated drug and one related to the innate antibacterial properties of the
surfactant-based carriers.
Acknowledgement: Financial support from MINECO CTQ2010-14897 and MAT2012-38047-CO2-02 is gratefully
acknowledged. Also financial support from Generalitat de Catalunya 2009SGR1331 is gratefully acknowledged.
132
PSS14
Study of the stability of polyethylenimine-decorated liposomes
Gerardo Prieto1,*, Juan Sabín1, Carmen Vázquez-Vázquez2, Federico Bordi3 and
Félix Sarmiento1
1
Biophysics and Interfaces Group, Departamento de Física Aplicada, Facultade de Física,Universidade
de Santiago de Compostela, Santiago de Compostela, Spain
2
Colloid Chemistry Group. Departamento de Química Física, Universidade de Vigo, Vigo, Spain.
3
Dipartimento di Fisica, Università di Roma “La Sapienza” and CNR-IPCF, Rome, Italy.
*
[email protected]
The study of the interaction of a cationic polymer as Polyethylenimine (PEI) with
phospholipid membranes is of special relevance for gene therapy because the PEI is a
potential non-viral vector to transfer DNA in living cells [1]. We have study the stability of
different PEI-decorated liposomes as a function of the headgroup of the lipid, the size of the
initial liposomes, pH, temperature and the charge ratio Rr. Results were analyzed using the
interaction potential proposed by Velegol and Thwar [2], that takes into account the effect of
the nonuniform distribution of the electric charge on the surface of the polyelectrolyte
decorated liposomes. The strong buffer capacity of the PEI alters the dependence of the zeta
potential of the complex with the PEI concentration. We have demonstrated that using the
proper buffer and the proper initial liposome size, a double charge inversion of the PEIdecorated liposomes built up with zwitterionic and anionic lipids can be observed. In such
cases, the complexes present a very rich
stability behavior with three different
ranges of PEI concentration where the
system is stable and two ranges where a
phase separation occurs. In “stable
regions” the aggregation leads to the rapid
formation of finite-size stable clusters
whose final size depends on the molar
charge ratio (Rr) between the polymer and
the liposome the pH and the temperature.
In the “unstable regions” the aggregates
keep growing until they eventually
flocculate [3].
Figure caption: Different ranges of pH studied depending on the zeta potential of
PEI and DOPC liposomes
Acknowledgements: This work was supported by the Spanish "Ministerio de Economía y
Competitividad" (Project MAT2011-26330). J. S. is supported by the “Ángeles Alvariño” Program of
the "Xunta de Galicia".
[1] Lungwitz, U.; Breunig, M.; Blunk, T.; Gopferich, A., Eur. J. Pharm. Biopharm. 2005, 60, 247-266.
[2] Velegol, D.; Thwar, P. K., Langmuir 2001, 17, 7687-7693.
[3] Sabín, J.; Vázquez-Vázquez, C.; Prieto, G.; Bordi F.; Sarmiento, F., Langmuir 2012, 28, 1053410542.
133
PSS15
Novel serine-based gemini surfactants for gene delivery:
physicochemical and compaction studies
Sandra G. Silva, Isabel S. Oliveira, M. Luísa C. do Vale and Eduardo F. Marques*
University of Porto (Portugal)
*
[email protected]
There is a growing need to develop delivery systems that protect and deliver biomolecules
effectively to the target cells. In this sense, surfactants are a class of compounds widely used in
pharmaceutical industry due to its high versatility and interfacial activity. Amino acid-based
surfactants usually have low cytotoxicity, are biocompatible and generally readily biodegradable.
For these reasons they are of great interest for biological applications, inter alia as non-viral drug
delivery vehicles [1].
Herein, we have developed and studied the aqueous phase behavior and aggregate
structure of three novel series of gemini amino acid-based surfactant derived from serine, in which
spacers based either on amide, amine or ester bonds were introduced between two amino acid
carboxylic acid groups. [2] The compounds have 12 carbons in each tail and in the spacer, with
general formula (12Ser)2COO12 (ester bond), (12Ser)2CON12 (amide bond) and (12Ser)2N12
(amine bond). The interfacial properties and self-assembly in water is explored through
conductivity and surface tension measurements. The aggregates formed in solution have been
characterized by video-enhanced high contrast light microscopy, dynamic light scattering and cryoSEM, with focus on spontaneously formed liposomes. The interaction and the compaction process
of these liposomes with DNA, at different charge ratios, have been further studied by means of
dynamic light scattering measurements, fluorescence microscopy and cryo-SEM.
Figure caption: General molecular structures of serine-based gemini surfactants and respective videoenhanced light microscopy images of spontaneously formed liposomes. Bar: 20 μm.
Acknowledgements: We kindly acknowledge the Portuguese Science Foundation (FCT) and FEDERCompete for financial support through projects PTDC/QUI-QUI/115212/2009 and Pest/CQUI/UI0081/2011.
[1] Yang, P.; Singh, J.; Wettig, S.; Foldvari, M.; Verral, R. E.; Badea, I., Euro. J. Pharm. Biopharm.
2010, 75, 311-320
[2] Silva, S. G.; Alves, C.; Cardoso, A. M. S.; Jurado, A. S.; Lima, M. C. P.; Vale, M. L. C.; Marques, E.
F., Euro. J. Org. Chem. 2013, 1758-1769
134
PSS16
Effect of the electrostatic interactions in the nanoparticle patterning using
driven evaporating menisci
Diego Noguera-Marín1,*, Carmen L. Moraila-Martinez1, Miguel Cabrerizo-Vilchez1 and
Miguel A. Rodriguez-Valverde1
1
Department of Applied physics, Campus Fuentenueva s/n, University of Granada, Spain.
*
[email protected]
Understanding the mechanisms that control the coating or patterning of nanoparticles over
a substrate [1, 2] is actually of great importance. These patterns may be achieved by drying of
particle suspensions, being the evaporation the leading mechanism [3]. There are, however, other
factors that can alter the particle deposition such as the wettability properties (substrate receding
contact angle, hysteresis, contrast between substrate and particle), velocity of contact line, solute
concentration or pairwise electrical interactions [4]. In this work we focused on the role of the
electrical interactions in the particle deposition on substrates [5]. We performed this study using
evaporating menisci formed between two vertical substrates but with driven contact lines, such as
reported by Bodiguel et al. [6]. The meniscus configuration is highly useful due to its similarities
with the industrial technique known as dip coating [7]. The substrates used were glass slides and
PMMA sheets (Goodfellow) and as nanoparticles we also chose glass (40nm, Attendbio) and
PMMA (90nm, Microparticles). Electrical interactions were tuned by varying the medium pH with
low-ionic strength buffer solutions. We found that the particle-particle and substrate-particle
electrostatic interactions were determinant for the final patterning (Figure). However, the substrate
receding contact angle (wedge-shape region), rather than the wettability contrast between substrate
and particle, could counterbalance the effects produced by the substrate-particle repulsion.
Figure caption: Deposits of glass nanoparticles over glass slides at different pH (different electrical charge).
Acknowledgements: This work was supported by the “Misisterio Español de Ciencia e Innovación” (projet
MAT2011-23339) and the “Junta de Andalucía” (projects P08-FQM-4325 and P09-FQM-4698).
[1] Joannopoulos, J. D.; Villeneuve, P. R.; Fan, S., Nature 1997, 386, 143-149
[2] Maenosono, S.; Dushkin, C. D.; Saita, S.; Yamaguchi, Y. Langmuir 1999 15 , 957-965
[3] Deegan, R. D.; Bakajin, O.; Dupont, T. F.; Huber, G.; Nagel, S. R.; Witten, T. A.
Nature 1997, 389, 827–829.
[4] Bhardwaj, R.; Fang, X.; Somasundaran, D.; Attinger D., Langmuir 2010, 26, 7833–7842.
[5]Moraila-Maríez, C.L.; Cabrerizo-Vilchez, M.A.; Rodruíguez-Valverde, M.A., Soft Matter 2013 9,16641673.
[6] Bodiguel, H.; Doumenec, F.; Guerrier, B., Langmuir 2010, 26 , 10758–10763
[7] Diao, J. J.; Sun, J. W.; Hutchison, J. B.; Reeves, M. E., Appl. Phys. Lett.2005, 87, 103113.
135
PSS17
Surface enhanced Raman scattering microscopy with substrates fabricated by
Au &Ag “nano-inks”
Sergey M. Novikov1,*, Lakshminarayana Polavarapu1, and Luis M. Liz-Marzán1,2
1
Bionanoplasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia-San
Sebastián, Spain
2
*[email protected]
Light interaction with nanostructured materials and nanostructures gives rise to various
fascinating optical phenomena occurring at nanoscale. One of the most remarkable effects in light
scattering by metal nanostructures is the strong up to several orders of magnitude and spatially localized
on the nanometer scale field intensity enhancement (FE). The FE occurs due to the resonantly excited
collective electron oscillations, known as localized surface plasmons (LSPs) [1]. The LSPs have a strong
sensitivity to the geometry, material, surrounding medium and configuration of metal nanostructures [2,
3]. The FE are extremely important for the practical applications as sensors, micro-optical devices, and
plays a major role in surface enhanced Raman scattering (SERS). One of the applications of SERS is the
detection of low molecular concentrations down to a single molecule [4]. Therefore, an important
research direction is the design of SERS substrates exhibiting strong, reproducible and robust FE effects.
On the other hand, the important requirements to SERS substrates are fast, simple and low-cost
fabrication, large and homogeneous sample areas. In this work we report about the fabrication and
characterization of uniform and efficient SERS substrates prepared by using Au & Ag nanoparticle inks
by solution process. Oleylamine capped gold and silver nanoparticles were prepared by two-phase
synthesis, which can be purified and concentrated into viscous solutions similar to printable “inks”.
Using such metal nanoparticle ‘‘nano-inks’’, we have demonstrated their applications for large scale
fabrication of efficient SERS substrates [5, 6]. These samples were examined using different methods:
UV-visible spectroscopy, atomic force and scaning electron microscopy, X-ray photoelectron
spectroscopy, and SERS. Using UV-visible spectroscopy we estimated the position of LSPs. By SEM
and AFM were examined the particle size, thickness of layer, and uniformity of surface coverage of
substrates. SERS was observed with excitation wavelengths of 532 nm and 785 nm using thiolated and
nonthiolated Raman probes such as Rhodamine 6G (R6G) and napthalenethiol, homogenously adsorbed
on such substrates. The concentration of molecules used in the experiments was below 10-8 M. The
obtained Raman images show the homogeneity of the fabricated structures. This results illustrate the
great opportunity of these structures as "ideal" SERS substrates. They are easy, fast and cheap to
fabricate, cover large, homogeneous areas with controlled position of LSPs and allow to detect low
molecular concentrations. Finally, the high reproducibility of the results renders these structures very
promising for sensing and biological applications
Acknowledgements: This work has been funded by the ERC through Advanced Grant Plasmaquo
[1] Giannini, V.; Fernández-Domínguez, A. I.; Heck, S. C.; Maier, S.A. Chem. Rev. 2011, 111, 3888.
[2] Novikov S. M, Evlyukhin A. B., Kuznetsov, A. I. Beermann J., Chichkov B. N. and Bozhevolnyi S. I., J. Opt. Soc.
Am. B., 2012, 29, 185.
[3] Beermann, J., Novikov S. M, Albrektsen O., Nielsen M. G and Bozhevolnyi S. I., J. Opt. Soc. Am. B. 2009, 26,
2370.
[4] K. Kneipp, Y. Wang, H. Kneipp, L. T. Perelman, I. Itzkan, R. R. Dasar, and M. S. Feld, , Phys. Rev. Lett. 1997,
78, 1667.
[5] Polavarapu L. and Liz-Marzán L. M., Phys. Chem. Chem. Phys., 2013 (In press)
[6] Sánchez-Iglesiasa A., Aldeanueva-Potela P., Nia W., Pérez-Justea J., Pastoriza-Santosa I., Alvarez-Pueblaa R.A.,
Mbenkumb B.N., Liz-Marzán L.M., Nonotoday, 2010, 5, 1, 21.
136
PSS18
Surface behavior of binary systems consisting of E1(70-87) peptide from HGV-C
virus and various phospholipids
M. Pujol*, A. Ortiz, M. Muñoz-Juncosa, J. Prat, V. Girona and M. A. Alsina
Physical-Chemistry Departament. Faculty of Pharmacy. University of Barcelona. IN2UB. Associate Unit
to CSIC: Protein and Peptides: physico-chemical studies.
Av. Joan XXIII s/n. Building A, Esc E, 3r. 08028 Barcelona
*[email protected]
The infection mechanism of viruses with capsid, such as GBV-C and HIV, is cell
penetration through a fusion process with the membrane. The binding of a virion to the target cell is
achieved by an anchoring of virus structural proteins to the surface of the cell membrane through
some conserved fragments, called fusion peptides (FP). The FP penetrates into the host membrane
providing a very close contact between the lipid bilayers of the virus and the cell, leading to their
fusion. A line of research was developed on the protective effect of GBV-C virus against the
development of AIDS in patients co-infected by HIV and GBV-C [1]. In recent years, our group
has been performing in vitro physical and chemical studies with different peptide sequences of
GBV-C and HIV-1 FP to ascertain their possible interactions [2, 3]. On the other hand, the role that
membrane lipids play in the fusion process of enveloped viruses such as FP HIV-1 is known [4, 5].
E1(70-87) peptide is an 18 amino-acid sequence from E1 structural protein of Hepatitis G virus
(GBV-C) which has been demonstrated as an effective inhibitor of HIV-1 leakage in vitro. In this
work, information on thermodynamic and packing properties for interactions between E1(70-87)
and phospholipids (DMPC, DPPC, DMPG, DPPG and DOPG) was derived from surface-pressure
(S-A) measurements and analysis. Brewster angle microscopy (BAM) images supported
conclusions on peptide arrangements at the air/water interface (Figure). We also provided
fluorescence microscopy images from supported mixed monolayers (LB films) to know about the
HIV-1 FP inhibition.
Figure caption: Surface-pressure area isotherm of E1(70-87) peptide on Hepes buffered subphase (pH 7.4) at 23qC
and BAM images at different compression pressures. Inset: compressional modulus vs. monolayer pressure.
Acknowledgements: This work was funded by Grant CTQ2009-13969-C02/01/BQU from the Ministerio de
Ciencia y Tecnología (Spain). The group was a consolidated research group from the Generalitat de Catalunya
(2009SGR560).
[1] Yuxian He et al. J. Biol. Chem. 2008, 283, 11126–11134.
[2] Sánchez-Martín, M.J. et al. Biochim. Biophys. Acta 2011, 1808, 2178-2188.
[3] Sánchez-Martin, M.J. Et al. J. Phys. Chem. B 2010, 114, 448-456.
[4] Bitler, A et al. Ultramicroscopy 2010,110, 694-700.
[5] Franquelim, H.G. et al. J. Am. Chem. Soc. 2008, 130, 6215-6223.
137
PSS19
Oligomer, protofibrillar and fibrillar aggregates from recombinant Human
Lysozyme: surface properties and cytotoxic effect
Eva D. Ruiz1, Guadalupe Burboa2, Josué Juárez1* Pablo Taboada3, Victor Mosquera3, and
Miguel A. Valdes1
1
Departamento de Física, Universidad de Sonora, Hermosillo, Sonora México.
Departamento de Investigación y Posgrado en Alimentos, Universidad de Sonora, Hermosillo, Sonora
México.
3
Departamento de Física de la Materia Condensada, Universidad de Santiago de Compostela, Santiago
de Compostela, A Coruña, España.
*[email protected]
2
Proteins represent one of the most versatile and important macromolecules in living
system playing important roles in different metabolic pathways for the maintenance of life.
The correct biological function of proteins depends of their self-assembly into well-defined
highly ordered structures (native state) [1]. On the other hand, protein misfolding and
abnormal assembly are related in over 30 human disorders, including Alzheirmer´s disease,
type II diabetes mellitus, transmissible spongiform encephalopathy, and so on. The pathology
of these human disorders is very likely correlated with self-assembly of amyloidogenic
peptides into various forms of aggregates such as oligomers, protofibrils, fibrils and senile
plaques [2]. Herein we monitorized the amyloid fibril formation of recombinant Human
Lysozyme (rHL) by enhanced fluorescence of ThT, DLS, surface tension measurements, FTIR
and AFM. Human lysozyme (HL) is a bacteriolytic enzyme, widely distributed in a variety of
tissues and body fluids, as the liver, articular cartilage plasma, saliva, tears and milk. HL has
been related in the formation of amyloid deposits in autosomal hereditary systemic
amyloidosis [3]. In this regards, we evaluated the toxicity of different rHL aggregates
(oligomers, protofibrils, and fibrils) over ARPE-19 cell line.
a
b
c
Figure caption: AFM image of rLH at different incubation time (a) 0 min, (b) 120 min and (c) 600 min
[1] Liu, L.; Zhang, L.; Niu, L.; Xu, M.; Yang, Y.; Wang, C.; ACS Nano 2011 , 5, 6001-6007.
[2] Adamcik, J.; Mezzenga, R.; Macromolecules 2012 , 45, 1137-1150.
[3] Dumoulin, M.; Johnson, R.J.K.; Bellotti, V.; Dobson, C.M.; Protein Reviews 2007 , 6, 285-308.
138
PSS20
On the initial-gap dependence of magnetorheological performance under
squeezing flow
J. A. Ruiz-López*, R. Hidalgo-Álvarez and J. de Vicente
Department of Applied Physics, Faculty of Sciences, University of Granada,
C/ Fuentenueva s/n, 18071-Granada, Spain
*
[email protected]
Magnetorheological (MR) fluids are field-responsive colloidal suspensions whose
mechanical properties change in the presence of a magnetic field. A typical MR fluid could be
characterized by its yield stress (i.e. the minimum stress value required for the suspension to
flow). Devices involving MR fluids definitely require a high yield stress and it has been
reported in the past to be enhanced by non-shearing flows [1]. The dependence of MR fluids
on typical parameters such as the iron particle concentration, the magnetic field strength or the
medium viscosity were investigated in a previous work and explained in terms of continuous
media theories [2, 3]. A strong depedence on the initial gap in parallel plates compression
experiments were found.
The initial gap dependence was previously investigated for electrorheological fluids
[4]. However, the squeeze flow behavior of MR fluids is different to ER fluids. Importantly, in
the latter, the electric field strength changes during the compression test (not in a MR fluid
experiment with non-magnetizable plates) and therefore it is not possible to split the electric
field strength and the initial gap dependences. Experiments with different initial gaps were
done and the wetting properties were tuned in order to investigate the surface tension effect.
Surface tension affects the resulting normal force acting on the plates especially at large initial
gap separations. Polytetrafluoroethylene coated surfaces were used to correct for this effect.
Finally, particle-level simulations were also carried out to be compared with experiments and
continuous media theories.
Acknowledgements: This work was supported by MICINN MAT 2010-15101 project (Spain), by the
European Regional Development Fund (ERDF) and by Junta de Andalucía P10-FQM-5977, P10-RNM6630 and P11-FQM-7074 projects (Spain). J.A.R.-L. acknowledges financial support by the “Ministerio
de Educación: Becas del Programa de Formación del Profesorado Universitario (FPU)” (AP2010-2144).
[1] Havelka, K. O; Pialet, J. W., CHEMTECH 1996, 36, 36-45.
[2] de Vicente, J.; Ruiz-López, J. A.; Andablo-Reyes, E.; Segovia-Gutiérrez, J. P.; Hidalgo-Álvarez, R.,
J. Rheol. 2011, 55, 753-779.
[3] Ruiz-López, J. A.; Hidalgo-Álvarez, R.; de Vicente, J., Rheol. Acta 2012, 51(7), 595-602.
[4] Tian, Y.; Wen, S.; Meng, Y., Phys. Rev. E 2003, 67, 051501.
139
PSS21
How chirality may affect to the self-aggregation pattern of lysine-based cationic
gemini lipids and their interaction with plasmid DNA?
Ribbon-type and Cluster-type lipoplexes
Ana L. Barrán-Berdón1,*, Mónica Muñoz-Úbeda1, Clara Aicart-Ramos2, Lourdes Pérez3,
Alberto Martín-Molina4, Pablo Castro-Hartmann5, Emilio Aicart1 and Elena Junquera1
1
Grupo Química Coloidal y Supramolecular, Dpto. Química Física I y 2Dpto. Bioquímica y Biología
Molecular I, Fac. Ciencias Químicas, Universidad Complutense de Madrid, Spain; 3Dpto. Tecnología
Química y Tensioactivos, IQAC-CSIC, Barcelona, Spain; 4Grupo de Física de Fluidos y Biocoloides,
Dpto. Física Aplicada, Universidad de Granada, Spain; 4Servei de Microscòpia, Universitat Autònoma
de Barcelona, Bellaterra, Spain.
*
[email protected]
Liposomes formed by several molar fractions of cationic lysine-derived lipid C6(LL)2
and the zwitterionic lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) were
mixed with plasmid pEGFP-C3 (pDNA) or linear double-stranded calf thymus DNA (ctDNA)
at different charge ratios to form lipoplexes. Lipoplex characterization was carried out by both
experimental (electrophoretic mobility/zeta potential, small angle X-ray scattering (SAXS),
cryogenic transmission electron microscopy (cryo-TEM) and negatively stained transmission
electron microscopy (NS-TEM)), and theoretical approaches. The electrochemical study
confirms that, in the presence of the mixed lipids and in contrast with what has usually been
found for linear DNA, the plasmid DNA is compacted with a large number of its Na+
counterions, thus yielding a much lower effective negative charge (q-pDNA) than that for
ctDNA (q-ctDNA), as reported recently by us >1@ for other lipoplexes. This finding is revealed
as crucial for an optimum and efficient lipoplex preparation, since a lower effective negative
charge implies a lower quantity of cationic lipid and, accordingly, a potential lower
cytotoxicity. TEM experiments reveal a rich variety of multilamellar nanostructures, from
ribbon-type (typically present for chiral lipids) to cluster-type structures (usually found in
cationic lipid/DOPE systems), the composition of the mixed liposome playing an important
role in the final morphology of the lipoplex. SAXS diffractograms confirm the existence of
these two types of multilamellar structures through a deconvolution process of the first peak of
diffractograms into two overlapping bands. On the other hand, the theoretical complexation
model that works with the renormalized charges of liposomes, DNA, and lipoplexes indicates
that when the surface charge of a liposome is large enough, an increase in the
cationic/zwitterionic lipid ratio does not imply an enhancement in the DNA complexation,
which confirms the crucial role played by the zwitterionic helper lipid >2@.
[1] Muñoz-Úbeda, M.; Misra, S; Barrán-Berdón, A. L.; Aicart-Ramos, C; Sierra, B.; Biswas, J;
Kondaiah , P; Junquera, E; Bhattacharya, S; Aicart, E, J. Am. Chem. Soc., 2011, 133, 18014-18017
[2] Barrán-Berdón, A. L.; Muñoz-Úbeda, M.; Aicart-Ramos, C.; Pérez, L.; Infante, M. R.; CastroHartmann, P.; Molina-Martin, A.; Aicart, E.; Junquera, E., Soft Matter, 2012, 8, 3368-3380.
140
PSS22
Lipid-poloxamer nanoemulsions as potential biological carriers
L. García-Jara1, A. Martín-Rodríguez1, J. A. Marchal-Corrales2, Gema Jimenez2,
J. M. Peula-García3,*
2
1
Biocolloids and Fluids Physics Group, Dpt. of Applied Physics, University of Granada, Spain.
Biopathology and Regenerative Medicine Institute (IBIMER), Biomedical Research Centre, University
of Granada, Spain.
3
Dpt. of Applied Physics II, University of Málaga, Spain.
*
[email protected]
The main objective of this work is the formulation of nanoemulsions able to transport
hydrophobic drugs. The prepared capsules of the nanoemulsion have a surfactant shell with
different poloxamers and lecithin, and a core of olive oil. The preparation method is based on
a high-pressure homogenized emulsion, which is one of the most efficient devices for particle
and droplet size reduction. The chemico-physical characterization of the nanocapsules played
a major role. In this way, the colloidal stability of the nanoemulsion is an important parameter
in order to preserve their biomedical properties. It has been demonstrated that this property
can be precisely controlled by the chemical structure of the shell interface. The presence of
hydrophilic polymers as poloxamers in the surface influences the colloidal stability of the
system improving an anomalous stabilization mechanism that maintains the integrity of these
nanocapsules with increasing salt concentration. In addition, the “in vitro” uptake process of
the nanocapsules was studied using two different human tumoral cell lines by fluorescence
microscopy and flow cytometry experiments, in order to know the influence of the surface
chemical structure in this process.
Figure caption: Study of the stability of the different formulated nanoparticles as a function of the time.
Acknowledgements: The authors thank the financial support given by the projects MAT2010-20370
(European FEDER support included, MICINN, Spain), and P07-FQM2496, P10-CTS-6270 and P07FQM3099 (Junta de Andalucía, Spain).
141
PSS23
DODAC:MO:DC-Chol/CHEMS lipoplexes for gene delivery
Odete Gonçalves1,2, Hugo Carvalho1,2, João P. N. Silva2, Andreia C. Gomes2 and
M. E. C. D. Real Oliveira1,*
1
Centre of Physics (CFUM), Department of Physics, University of Minho, Campus of Gualtar, 4710-057
Braga, Portugal.
2
Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho,
Campus of Gualtar,4710-057 Braga, Portugal
*
[email protected]
Dioctadecyldimethylammonium Bromide or Chloride (DODAX, X representing Bror Cl- counter ions):1-monooleoyl-rac-glycerol (MO) liposomes have recently been described
as new promising alternative to common transfection reagents, due to the pioneering
application of Monoolein (MO)as helper lipid in lipoplex structures [1-3]. This work was
focused on the development and characterization of lipoplexes based on DODAC:MO
liposomes with the inclusion of a cholesterol derivative 3
[N-(N’,N’dimethylaminoethane)carbamoyl cholesterol (DC-Chol) or Cholesteryl hemisuccinate
(CHEMS) in order to improve transfection efficiency. MO, a neutral lipid which tends to form
inverted bicontinuous cubic mesophases, seems to function well as a helper lipid since it
affects the physicochemical properties of the lipoplexes and interferes with lipoplex-cell
interactions. DC-Chol is a synthetic cationic molecule derivate from cholesterol. It is
frequently used in liposome formulations due to its biocompatibility, the stability it confers to
lipid membranes and the ability to enhance transfection efficiency [4]. CHEMS is another
cholesterol derivative, known to increase the fusogenic capacity of lipoplexes when the
environmental pH is below the pKa (pH 5.8) by forming a hexagonal phase [5].
The results show that the inclusion of DC-Chol does not significantly affect the
physicochemical properties (namely size, stability and surface charge) of the nanoparticles but
seems to potentiate transfection efficiency and decrease citotoxicity depending on the molar
ratio of each component in the liposomal formulation. DODAC:MO:CHEMS lipoplexes are
expected to further improve transfection efficiency due to a higher capacity to fuse with
biological membranes in acidic environments such as those found in endosomal pathways and
in tumors and inflammatory tissues.
Acknowledgments: This work was supported by FEDER through POFC – COMPETE and by national
funds from FCT through the project PEst-C/BIA/UI4050/2011 (CBMA) and PEst-C/FIS/UI0607/2011
(CFUM). We acknowledge spin-off Nanodelivery-I&D in Bionanotechnology for access to specific
equipments.
[1] M. E. C. D. Real-Oliveira, et al. “Use of Monoolein as a New Auxiliary Lipid in Lipofection”,
International Patent n. WO2010/020935, W.I.P. Organization, 2010. p. 1-27.
[2] M. E. C. D. Real-Oliveira, et al. “Aplicação da Monooleína como Novo Lípido Adjuvante em
Lipofecção, in Portuguese Patent n. PT2011/104158, I.N.d.P. Industrial. 2011. p. 1-28.H.
[3] Neves Silva, J. P.; Oliveira, A. C. N.; Casal, M. P. P. A.; Gomes, A. C.; Coutinho, P. J. G.; Coutinho,
O. P.; Real Oliveira, M. E. C. D., Biochim. Biophys. Acta, 2011, 1808, 2440-2449.
[4] Balazs, D. A; Godbey, W. T., J. Drug Deliv. 2011, 2011, 326497.
[5] Hafez, I. M.; Ansell, S.; Cullis, P. R., Biophys. J. 2000, 79, 1438-1446.
142
PSS24
Development and characterization of fluorescent microspheres as a probe for
particle uptake assays by flow citometry
Cecilia Sóñora1, Ana Hernández1, Iris Miraballes-Martínez2,*
1
Cátedra de Inmunología, Facultad de Ciencias. Universidad de la República (UdelaR). URUGUAY
2
Laboratorio de Biotecnología, Polo Tecnológico de Pando, Facultad de Química,
Universidad de la República (UdelaR). URUGUAY
*
[email protected]
The internalization of microparticles by cells can occur by different mechanisms such as
endocytocis, pinocytosis or phagocytosis according to the cell type and the particle properties.The
particle uptake by cells can be evaluated by microscopy (optical or confocal) or flow cytometry.
Some of these methods use fluorescent probes >1,2@. The objective of this work was the 2- step
preparation >3,4@ of fluorescent microspheres, their characterization and evaluation as probe in
particle uptake assays by two different human phagocytic cells (dTHP-1 and monocytes) with flow
cytometry measurements for functionality assays.
The human monocytic leukemia cell line THP-1 (ATCC) was differentiated to
macrophage phenotype with 3 days incubation with 100 nM phorbol 12-myristate 13-acetate;
differentiated THP-1 (dTHP-1) exhibit a more potent phagocytic ability than non differentiated
cells>5@. Monocytes were purified from fresh peripheral blood according to standard procedures.
Monocytes or dTHP-1 cells were mixed with the microparticles in tissue cultures plates in
ratios from 1:100-1:1000 and incubated for two hours at 37°C and 4°C, in RPMI 1640 culture
medium. After incubation, cells were harvested and analyzed in a FACScalibur flow cytometer
(BD Biosciences). The increase in green fluorescence intensity (%'MFI) and the percentage of
fluorescent cells (ingesting cells) was evaluated in relation with basal condition (4°C). Free
particles did not interfere with the forward versus side scatter dotplots, and a gate was used for each
analysis to exclude debris and non monocytic cells.
25.2%, 37.3% and 48.4% of monocytes exhibited significant green fluorescence when
incubated with particles in the ratios 1:100, 1:500 and 1:1000 respectively. 31.8±8.9% ingesting
cells were observed in three independent experiments with dTHP-1 cells, with 412±96 %'MFI at
1:1000 cell:particle ratio. No significant difference was observed when the assay was done in
presence of human serum (opsonization effect).
Our results show that microparticles are efficiently internalized in a non-opsonized form
by two cellular types with different intrinsic phagocytic ability. The selected method of preparation
of the fluorescent microspheres allows to obtain this reagent which can be modified for different
assays in flow citometry
Acknowledgements: Comisión Sectorial de
República(UdelaR), URUGUAY.
Investigación Científica, (CSIC) Universidad de
la
>1@ Ambruso, D.R. Phagocyte function. In Phagocyte production and function following burn injury; Peterson,
V.A. and Ambruso, DR., Eds.; Austin, TX: RG Landes Company, 1994, pp 60- 92.
>2@ Nares, S.; Wahl, SM. Monocytes and macrophages, in Measuring immunity, MT Lotze and AW Thomson,
E. Elsevier AP; California, 2005; pp 299- 311.
>3@ Peula, J.M.; de las Nieves, F.J.- Colloids Surf. A: Physicochem. Eng. Aspects 1994, 90, 55-62
>4@ Hermanson, G.T.- Bioconjugate Techniques, Elsevier, 1996.
>5@ Daigneault M. et al. Plos One. 2010.5,1,e8668.
POSTERS
145
P01
Hybrid corrole-gold nanoparticles
Joana F. B. Barata*, Ana L. Daniel-da-Silva, M. Graça, P. M. S. Neves,
José A. S. Cavaleiro and Tito Trindade
Department of Chemistry – QOPNA and CICECO,
University of Aveiro, 3810-193 Aveiro, Portugal
*
[email protected]
Colloidal gold has been used in medicine for a long time; for example it has been
reported that the alchemist Paracelsus (1493-1541) prescribed its use in the form of Aurum
Potabile as a panacea for a number of diseases and, since the twenty century, it has been used
as a pharmaceutical formulation to relieve joint inflammation due to rheumatoid arthritis.
More recently, with the advent of nanomedicine, gold nanoparticles have found application in
new forms of diagnostic and therapeutic strategies. For example, gold nanoparticles have been
investigated as a drug delivery in new approaches for cancer treatment such as in
photodynamic therapy.[1] Photodynamic therapy (PDT) is a technique in which lightmediated activation of photosensitizing agents results in the generation of reactive oxygen
species which destroy target tissues by inducing apoptosis or necrosis of the malignant cells.
Tetrapyrrolic macrocycles play a central role as adequate photosensitizers for
PDT.[1] In this context, and comparatively to other macrocyclic systems such as porphyrins,
corrole compounds and their metal complexes have been less investigated. We have been
interested in developing new hybrid nanoparticles comprising corrole molecules coupled to
inorganic particles in order to evaluate the potentiality of these type of conjugates for PDT.[2]
In this communication, we will report the synthesis of hybrid corrole-Au nanoparticles
obtained from the in situ reduction of Au(III) in the presence of functionalized corroles. The
influence of the chemical functionalization of the corrole molecules on the final properties of
the materials has been investigated. As such, the hybrid nanostructures were characterized by
adequate techniques that include TEM, FTIR and XPS. Optical experiments have been
performed with these materials and the results will be discussed here in the context of their
usefulness in PDT.
Acknowledgements: Thanks are due to Fundação para a Ciência e a Tecnologia (FCT, Portugal),
European Union, QREN, FEDER and COMPETE for funding the QOPNA and CICECO research units
(project PEst-C/QUI/UI0062/2011 and Pest-C/CTM/LA0011/2011). J. F. B. Barata thanks FCT-MCTES
(Portugal) for her Post-Doctoral grant SFRH/BPD/63237/2009. A. L. Daniel-da-Silva thanks FCT, FSE
and POPH for funding. We thank the RNME (National Electronic Microscopy Network) for SEM
facilities.
[1] Jelveh, S.; Chithrani, D. B. Cancers 2011, 3, 1081-1110.
[2] Barata, J. F. B.; Daniel-da-Silva, A. L.; Neves, M. G. P. M. S.; Cavaleiro, J. A. S.; Trindade, T. RSC
Adv., 2013, 3, 274-280.
146
P02
Optimization of a nanostructured lipid carriers formulation for porphyrin
delivery based on factorial design
Liliana Damas1, Carla Vitorino1, João J. Sousa1, Marta Piñeiro2, Alberto A. C. C. Pais2,*
1
Centro de Estudos Farmacêuticos (CEF), Faculty of Pharmacy, University of Coimbra, Portugal
2
Department of Chemistry, University of Coimbra, Portugal
*
[email protected]
Nanostructured lipid carriers (NLC) have been studied in the last years for
administration through different pathways, playing an important role in drug delivery [1]. In
the present work, a central composite design
(Figure) was applied to optimize a
nanostructured lipid carriers formulation
composed of precirol, oleic acid and stabilized
by Tween 80®. NLC were produced by hot high
pressure homogenization, and evaluated as drug
carriers
for
porphyrins
(5,10,15,20tetraphenylporphyrin
and
meso-Tetra(4carboxyphenyl)porphine).
The
selected
independent variables, x1, x2 and x3 comprised
emulsifier concentration, liquid:solid lipid ratio,
and lipid phase concentration, respectively, while
the dependent variables or responses included
particle size, polydispersity index and zeta
potential.
Figure caption: Central composite design for a three factor experiment [2].
Experimental results of 15 formulations yielded mean particle size ranging from 105
to 534 nm, with a polydispersity index from 0.20 to 0.32, and zeta potential values ranging
from -16.9 to -34.5 mV. The liquid:solid lipid ratio constituted the most important parameter,
followed by the emulsifier concentration. Higher liquid:solid lipid ratios, as well as higher
emulsifier concentrations, induce a decrease in particle size. A positive coefficient indicated
that a higher lipid phase concentration leads to an increase in particle size, D. In summary,
using a second-order model we obtained:
D=182.7–33.7x1–82.8x2+42.1x3–4.2x1x2+4.4x2x3–7.8x1x3+20.8x12+43.0x22+17.5x32+4.6x1x2x3
and an optimal formulation was determined, with mean particle sizes ranging from 91 to 156
nm, with a polydispersity index from 0.29 to 0.31, and zeta potential values ranging from 31.7 to -37.3 mV. The NLC were able to incorporate the porphyrins under study, with no
significant changes in particle size and zeta potential, constituting promising carriers for these
compounds. The application of experimental design provided a deeper understanding of the
system, and also proved to be a useful tool for the optimization of the nanoparticle
formulation.
[1] Vitorino, C.; Carvalho, F. A.; Almeida, A. J.; Sousa, J. J.; Pais, A. A. Colloids Surf. B: Biointerfaces,
2011,84, 117.
[2] Adapted from Armstrong, N. Anthony - Pharmaceutical Experimental Design and Interpretation. 2nd
ed. USA: Taylor & Francis Group (2006). ISBN 0-415-29901-2.
147
P03
Chitosan or Alginate-coated iron oxide nanoparticles: A comparative study
J. Estelrich1,2,*, J. Castelló1, M. A. Gallardo1,2 and M. A. Busquets1,2
1
Departament de Fisicoquímica. Facultat de Farmàcia. Universitat de Barcelona. Avda Joan XXIII, s/n.
08028 Barcelona.
2
08028 Barcelona.
*
[email protected]
The preparation and characterization of stable aqueous suspensions of
superparamagnetic iron oxide nanoparticles stabilized with chitosan (CHI) or with alginate
(ALG) is reported. Both polymers present many relevant properties: nontoxicity,
biocompatibility and biodegradability which ensure their suitability for biomedical
applications [1, 2]. Synthesis of particles of iron oxide was carried out via a controlled coprecipitation method [3]. The obtained particles presented a diameter of approximately 12 nm,
a value that ensures superparamagnetic properties and their suitability for biomedical
applications. The optimal concentration of polymer needed for coating the nanoparticles was
determined by adsorption isotherms. When coated with polymers, a comparison between the
properties afforded by chitosan and alginate has been performed by measures of the
hydrodynamic ratio, -potential, content of polymer coating the particles by
thermogravimetry, high-resolution transmission electron microscopy, magnetic properties and,
finally, the stability in biologic media. Moreover, the effect of glutaraldehyde as a chitosan
crosslinking agent on the stability of the samples has been tested [4].
ALG-coated nanoparticles presented a mean value of 50-55 nm in diameter, whereas
the size of CHI-coated nanoparticles was 80-120 nm. The addition of glutaraldehyde 25% (wt
%) reduced considerably the size. Both types of particles showed similar values of saturation
magnetization (59.3 emu g-1 for ALG-coated nanoparticles, and 56.8 emu g-1 for the coated
with CHI). When nanoparticles were kept in contact with human multi-sera at 37oC,
significant differences between both types of nanoparticles were observed. ALG-coated
nanoparticles were stable up to nine days, but CHI-coated nanoparticles were stable only for
two days. Agglomeration and phase separation were the main effects observed.
Acknowledgements: This work was supported by the grant MAT2012-36270-C04-03 from the Spanish
Ministerio de Economía y Competitividad.
[1] Lee, K. Y. Mooney, J. Progr. Polym. Sci. 2012, 3, 106-126.
[2] Calero, N., Muñoz, J., Ramírez, P., Guerrero, A. Food Hydrocolloid 2010, 24, 659-666.
[3] Berger, P., Adelman, N. B., Beckman, K. J., Campbell, D. J., Ellis, A. B., Lisensky, G. C. J. Chem.
Ed. 1999, 76, 943-948.
[4] Monteiro, A. C., Airoldi, C. Int. J. Biol. Macromol. 1999, 26, 119-128.
148
P04
Broadband dielectric spectroscopy to study colloidal materials.
E. Galera-Cortés1, J. D. Solier1,*, J. Estelrich2 and R. Hidalgo-Álvarez3
1
Departamento de Física Aplicada, Universidad de Extremadura, Avda. de Elvas s/n, 06071 Badajoz,
Spain.
2
Departament de Fisicoquímica. Facultat de Farmàcia. Universitat de Barcelona. Avda Joan XXIII, s/n.
08028 Barcelona. Spain.
2
08028 Barcelona.
3
Departamento de Física Aplicada, Universidad de Granada, Campus Fuentenueva, 18071 Granada,
Spain.
*
[email protected]
Dielectric spectra of a aqueous colloidal suspension show several relaxations ranging
from DC to GHz frequencies, and the broadband dielectric spectroscopy (BDS) is the
experimental technique used to explore this range. This work shows how useful this technique
is in order to study the electric behaviour of latex and liposomes. The dielectric spectra of
latex show two relaxations. The low-frequency dielectric dispersion (LFDD) is owing to the
polarization of the electric double layer around the particles. This is reasonably well fitted by
the theoretical expressions given by two models: a simplified standard model (not including
anomalous conduction) and a generalized one (including anomalous conduction). The highfrequency dielectric dispersion Maxwell–Wagner (MW) is due to the ionic charges distributed
near the surfaces that separate phases with different dielectric constant and conductivity. This
relaxation is well adjusted by the theoretical expressions given by Maxwell–Wagner–
O’Konski theory. Additionally, it would be an option to include the effects of ion mobility in
the Stern layer in order for the values of the -potential (obtained from electrophoretic and
dielectric data) to be compatible with each other. On the other hand, in liposome suspension,
the dielectric permittivity spectra show two dispersion regions, for frequencies around 25 and
under 0.3 MHz. The first dispersion is attributed to rotational diffusion of zwitterionic
phospholipid molecules, and the second one is caused by diffusion of the counterion
atmosphere along the liposome surface. The lateral diffusion coefficient (Dlat) was obtained
from the dielectric relaxation time of zwitterionic phospholipids in the bilayer. These
measurements were performed for different pH values and salt concentrations (KBr), as well
as in two different physical phases of the phospholipid: liquid-crystalline and gel. It was
analyzed how these factors affect the lateral diffusion of dipolar phospholipids in the bilayer.
Therefore, broadband dielectric spectroscopy is a powerful tool to study the phenomena of
polarization, conduction, diffusion as well as the electrokinetic properties of a colloidal
suspension.
Acknowledgements: This work has been supported by the MICINN MAT 2010-15101 Project (Spain),
by the European Regional Development Fund (ERDF). R. Hidalgo-Álvarez thanks the financial support
received from CEI-Biotic 20F12/16 and P10-FQM-5977 Project (Spain). J. Estelrich thanks the financial
support received from MAT2012-36270-C04-03 Project (Spain).
149
P05
Cleaning of dried starch in stainless steel with surfactant solutions containing
micro- and nanoparticles
E. Jurado*, Jose M. Vicaria, Otilia Herrera-Márquez, A. Plaza
Departamento Ingeniería Química. Universidad de Granada.
Avda Fuentenueva s/n. 18071 – Granada (Spain)
*
[email protected]
The use of nanoparticles in detergent formulations can enhance their cleaning performance due
to mechanisms based on physico-chemical interactions with the substrate and the soil present in the
system, facilitating their removal. In this contribution we analyze the influence of the inclusion of silica
particles in cleaning of dried starch .The silica particles were supplied by Evonik Industries AG (HanauWolfgang, Germany), Their surface areas and sizes were 500 m2/g -50 μm, 200 m2/g – 12 nm and 380
m2/g-7 nm.
To evaluate the detergency, gelatinized starch was used to dirty spheres made with stainless
steel fibers. The dirty spheres were dried in oven at 60 °C for 12 h. The washing tests were performed in
the Bath-Substrate-Flow (BSF) device proposed by [1]. This device simulates a cleaning-in-place
system. Several samples are extracted in each experiment at different times. The total amount of soluble
carbohydrates in the cleaning solution was analyzed by the colorimetric assay of phenol-sulfuric acid.
Response surface methodology was used to analyze the experimental results. The variables assayed
were flow (30-60 L/h), pH (7-13), particle concentration (0.1-1 g/L Sipernat 50). The washing was made
for 45 min and 40ºC. The detergency (De (%)) was evaluated as De = Wbath·100 / Wstarch, where Wbath is
the amount of dirt in the washing bath and Wstarch the total starch added to the substrate at the beginning
of the cleaning process. [2]
The results indicate that the inclusion of nanopartícles had no influence on cleaning starch. The
most significant variables in the washing process were pH and flow. At pH 7-10, the detergency obtained
in the absence of surfactant was next to 0. At pH=13, the detergency was 15,4% with a flow rate of 30
L/h and 30,7% at 60 L/h. Experiments with the surfactant Findet 1214N/23 (ethoxylated fatty alcohol)
supplied by Kao Corporation, were also carried out. The detergency obtained in the tests conducted with
1 g/L of Findet 1214N/23 at pH 7-10 was next to 0 again. The detergency obtained in experiments that
contains 0,1 g/L of particles was similar to the experiments made without surfactant. However, the
detergency is reduced significantly with increasing concentration of particles (1 g/L) (23,3% at 30 L/h
and 34,5% at 60 L/h). This result suggests that the surfactant is adsorbed on the Sipernat particles and
there is a reduction of the cleaning efficiency. The adsorption of surfactant (Findet 1214N/23) by
microparticles made of hydrophilic silica (Sipernat 50) and nanoparticles made of fumed silica (Aerosil
200 and Aerosil 380) was measured by standard tests. The surfactant concentration assayed was 1 g/L
and the particle concentration was between 0.1-1 g/L. The surfactant concentration was measured using
the iodine-iodide colorimetric method [3]. It was observed to be adsorbed 52% of surfactant by Sipernat
50 and almost 20% by Aerosil 200 and Aerosil 380. This adsorption of the surfactant on the
nanoparticles interfere with the washing process, preventing the surfactant from acting on the soil
retained in the substrate.
Acknowledgements: The authors are grateful the financial support provided by Spanish and Andalusian Governments
through the projects CTM2010-16770 and P07-TEP-02603.
[1] Jurado, E.; Bravo, V.; Bailón, R.; Núnez, J.; Altmajer, D. Método BSF (Baño-Sustrato-Flujo) y dispositivo para la
evaluación de la eficacia detersiva y dispersante de tensioactivos, de coadyuvantes de la detergencia y de
composiciones de detergentes de superficies duras. Spanish Patent P2002/02364.
[2] Jurado, E., Bravo, V., Altmajer, D., Siqueira, R., Food Hydrocolloids 2011, 25, 647-653
[3] Jurado, E., Fernández-Serrano, M., Núñez, J., Luzón, G., Lechuga, M., Tenside surfactants detergents 2002, 39, nº
5, 154-159.
150
P06
Hybrid Magnetic Polymeric Nanoparticles Prepared via Miniemulsion
Polymerization
Chariya Kaewsaneha1,2, Pramuan Tangboriboonrat2, Duangporn Polpanich3,
and Abdelhamid Elaissari1,*
1
University of Lyon, F-69622, Lyon, France; University Lyon-1, Villeurbanne; CNRS, UMR 5007,
LAGEP- CPE; 43 bd 11 Novembre 1918, F-69622 Villeurbanne, France
2
Department of Chemistry, Faculty of Science, Mahidol University, Phyathai, Bangkok 10400, Thailand
3
National Nanotechnology Center (NANOTEC), Thailand Science Park, PathumThani 12120, Thailand
*
[email protected]
Magnetic polymeric nanoparticle (MPNP) and/or Janus magnetic nanoparticle
(JMNP) consisting of magnetic nanoparticles (MNPs) embedded in polymer matrix were
successfully prepared via the miniemulsion polymerization [1,2]. Since the particle nucleation
occurs primarily within the monomer droplet, not only the size of particle could be controlled
at the beginning but also its morphology was manipulated by using different types of initiator.
In this case, MNPs were prepared by the co-precipitation method and then were coated with
oleic acid before mixing with styrene and acrylic acid monomers. The MPNP with
homogeneous distribution of MNPs (41%) in the polymer matrix was obtained when using
potassium persulfate (KPS) as initiator and divinyl benzene as crosslinking agent (Figure A)
[2]. To obtain JMNP, an oil soluble initiator 2,2’-azobis(2-isobutyronitrile) was introduced
instead of KPS [3]. The controllable phase separation between the polymer matrix and the
encapsulated MNPs caused the stable spherical Janus particles containing MNPs (15%)
located on one side of polymer particle (Figure B). Both MPNPs and JMNPs could be easily
separated by an external magnet.
Figure caption: TEM images of MPNP (A) and JMNP (B) [2].
Acknowledgements: The authors thank and appreciate the research grant (RTA5480007) from The
Thailand Research Fund (TRF)/Commission on Higher Education to P.T., and the scholarship from TRF,
Mahidol University and French Government through the Royal Golden Jubilee Ph.D. Program (Grant
No. PHD/0174/2552) to the PhD student C.K.
[1] Charoenmark, L.; Polpanich, D.; Thiramanas, R.; Tangboriboonrat, P. Macromol Res, 2012, 20, 590.
[2] Kaewsaneha, C., Opaprakasit, P., Polpanich, D., Smanmoo, S., Tangboriboonrat, P. J. Colloid
Interface Sci., 2012, 377, 145-152.
[3] S. Braconnot, S., Eissa, M.M., Elaissari, A. Colloid. Polym. Sci. 2013, 291, 193-203.
151
P07
SERS Performance of Gold Nanostars
J. Langer1,*, A. Shiohara1, A. Sánchez-Iglesias1 and L. M. Liz-Marzán1,2
1
Bionanoplasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia-San
Sebastián, Spain.
2
*
[email protected]
Surface enhanced Raman scattering (SERS) can take place when a molecule is
adsorbed on a rough metallic surface or a plasmonic nanostructure and becomes more and
more popular as an analytical tool to detect very low concentrations of molecules. Plasmonic
Au nanoparticles (NP) offer a great potential for biosensing due to their low toxicity, chemical
inertness and plasmon tunability within the near-infrared (NIR) region, which is of advantage
for in vivo applications. Au NPs with sophisticated shapes and complex compositions have
been fabricated and intensively explored for SERS spectroscopy [1]. Very promising candidates for biomedical applications are star-shaped nanostructures [2-5] because of their surface
plasmon resonances, which can be tuned into the NIR region by controlling the branch aspect
ratio [3] and the strong electromagnetic field enhancement (hot spots) located at the tips [2].
In general, SERS depends strongly on a variety of factors, e.g. the matching of
plasmon excitation and Raman laser wavelength, the electronic nature and surface chemistry
of the analyte and aggregation state of the analyte-NP system. In order to stabilize, protect and
functionalize the NP surface, different polymer coatings or surfactants are used, which can
also affect the scattering properties.
In this contribution, we present a systematic and comparative study of the SERS
performance of polyvinylpyrrolidone (PVP), polyethylene glycol (SHPEG) and silver (Ag)
coated, citrate (cit) and sodium dodecyl sulfate (SDS) stabilized Au nanostars in aqueous
solution using dyes and thiols as analytes for two types of binding modes to the bare star
surface. The dye molecules astra blue (AB) and rhodamine 6G (R6G) interact with the
nanoparticles via electrostatic forces, whereas the thiolated molecules 1-naphthalenethiol
(1NAT), mercaptobenzoic acid (MBA), aminothiophenol (ATP) and benzenedithiol (BDT)
are covalently bound to Au.
Regardless of the coating type, the strongest SERS signal was observed for AB. PVP
coated nanostars show a very good SERS performance and stability with both dyes and thiols.
The SERS signals of R6G with PEG coated or SDS-Au nanostars are lower than for PVP
coating, and the detection of 1-NAT is not possible. Cit-Au nanostar colloids show high SERS
of MBA, ATP or BDT, but are not stable in solution and tend to fast aggregation. Ag coating
of the Au nanostar significantly enhances the AB SERS signal compared to the cit-Au
nanostar, but without further protection the stability remains problematic.
[1] Burda, C.; Chen, X.; Narayanan, R.; El-Sayed, M.; Chem. Rev. 2005, 105, 1025.
[2] Barbosa, S.; Agrawal, A.; Rodriguez-Lorenzo, L.; Pastoriza-Santos, I.; Alvarez-Puebla, R. A.;
Kornowski, A.; Weller, H.; Liz-Marzan, L. M.; Langmuir 2010, 26, 14943.
[3] Yuan, H.; Khoury, C.G.; Hwang, H.; Wilson, C.M.; Grant, G.A.; Vo-Dinh, T., Nanotechnology 2012,
23, 075102.
[4] Rodriguez-Lorenzo, L.; Krpetic, Z.; Barbosa, S.; Alvarez-Puebla, R.A.; Liz-Marzan, L. M.; Prior, I.
A.; Brust, M.; Integr. Biol. 2011, 3, 922.
[5] Schütz, M.; Steinigeweg, D.; Salehi, M., Kömpe, K., Schlücker, S.; Chem. Commun. 2011, 47, 4216.
152
P08
PS-PAA-Capped Gold Nanostars as SERS substrate for the detection of
hydrophobic molecules
Andrea La Porta1,*, Ana Sánchez-Iglesias1, Marek Grzelczak1 and Luis M. Liz-Marzán1
1
Bionanoplasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 DonostiaSan Sebastián, Spain.
*
[email protected]
Surface-Enhanced Raman Scattering (SERS) is a powerful tool to detect and analyze
very small amount of molecules on a metallic substrate. The key aspect of this technique is the
strong local enhancement of the incident electric field due to the Localized Surface Plasmon
Resonance (LSPR) of metal nanostructures. Star-shaped nanoparticles represent an interesting
option for SERS substrate because of the intense electric field enhancement present at the tips
and in the areas between two or more adjacent tips (hot spots). In this work, SERS spectra of
Oxazine 720 in PS-PAA capped gold nanostars (AuNSs) are presented. We investigated the
change in the SERS intensity for different analyte concentrations. The comparison between
Raman and SERS spectra shows that the analyte is able to go through the external polymeric
sphere and get closer to the AuNSs surface. Further treatments with tetrahydrofuran (THF)
vapour reveal a decrease in the signal intensity, this confirming the fact that Oxazine
molecules go far away from the AuNSs’ surface because of the concentration gradient.
Figure caption: Gold Nanostars: Invididual (a) and Assemblies (b).
153
P09
Comb-Like Acrylic-Based Polymer Latexes Containing Nano-Sized
Crystallisable Domains
E. Mehravar*, J. R. Leiza, and J. M. Asua
POLYMAT, University of the Basque Country UPV/EHU.
*
[email protected]
(Liquid) crystalline domains are known to impart improved mechanical properties for
solvent born systems [1]. However, little is known about the synthesis of these domains and
their properties in water borne acrylic-based latex particles [2]. These hard and tough domains
can be introduced to a polymer matrix by using crystallisable side-chains of the polymer
backbone obtained via copolymerization of monomers having long side chains with
conventional monomers (comb-like crystalline polymers) [3]. In this work the toughening of
the soft acrylic-based latex particles via introducing crystallizable units within the waterborne
latex particles was studied. The polymer latexes were synthesized via 2-step miniemulsion
copolymerization of a crystallizable long side chain acrylate monomer (stearyl acrylate, SA)
and short side chain (meth)acrylates (methyl methacrylate MMA, n-buthyl acrylate BA and
Acrylic acid AA) in different strategies. Thermal characterization and mechanical properties
of the films prepared from these latexes indicated that the monomer composition and also
copolymerization process conditions have significant effects on the crystallinity and the
mechanical properties of copolymer latexes. The heat of fusion and crystallinity of the
copolymer latexes synthesized with the same copolymerization process decrease with
increasing of short side chain (meth)acrylates concentration. The findings suggested that the
presence of PSA crystalline domains increases the mechanical properties of the latexes (Figure
1). Conversely, the PSA amorphous states decrease the glass transition temperature and
mechanical properties of the copolymer latexes [4].
a
b
Figure caption: The stress-strain behavior of latexes synthesized with different monomer composition
obtained from seed (poly stearyl acrylate) miniemulsion copolymerization of short side chain
(meth)acrylates (a) and the enlargement of elastic region (b).
[1] Chen, D. S.; Jones, F. N., J. Appl. Polym: Sci. 1988, 36, 141-163.
[2] Parker, H. Y.; Merritt, R. F.; Fu, Z.; Ibbitson, S. A.; Gore, R. H.; Wolfersberger, M. A., U. S. Patent
6,552,147, 2002.
[3] O'Leary, K.; Paul, D. R., Polymer 2006, 47, 1245-1258.
[4] Jordan Jr, E. F., J. Polym. Sci., Part A: Polym. Chem. 1971, 9, 3367–3378.
154
P10
Synthesis and photocatalytic properties of titanates nanotubes sensitized by
crystalline Ag2S nanoparticles
Márcia C. Neves1,*, A. J. Silvestre2, M. R. Nunes3, O. C. Monteiro4
1
Ciceco and Chemistry Department, University of Aveiro,3810-193 Aveiro, Portugal
2
Department of Physics and ICEMS, Instituto Superior de Engenharia de Lisboa,
1959-007 Lisboa, Portugal
3
CCMM, Department of Chemistry and Biochemistry, Faculty of Sciences,
University of Lisbon, 1749-016 Lisboa, Portugal
4
CQB, Department of Chemistry and Biochemistry, Faculty of Sciences,
University of Lisbon, 1749-016 Lisboa, Portugal
*
[email protected]
Nanostructured materials have become one of the most important research subjects,
being established a remarkable development in a wide assortment of scientific fields. Despite
all known successes, the control of the materials’ intrinsic properties is still difficult and
challenging. The synthesis of nanocomposite materials has been one of the most fruitful
methods for accomplish this propose: by combining several materials it is possible to prepare
new materials with improved and innovated properties. Titanate nanotubular structures (TNS)
are very interesting since they combine the properties and applications of conventional TiO2
nanoparticles (e.g., photocatalytic activity) with the properties of layered titanates (e.g., ionexchange facility) [1]. Nevertheless, the synthesis of TiO2-based materials either with a
broader range of light absorption and/or a lower charge recombination rate would be an
important step toward the development of higher efficient photoactive materials [2].
In this works a single source method is described to prepare nanocrystalline
Ag2S/TNS, aiming to obtain new nanostructured materials with improved optical and
photocatalytic properties. The TNS modification is based on the in situ nucleation of
crystalline Ag2S nanoparticles onto the TNS surface. The prepared materials were structural,
morphological and optical characterized. The application of these new photoactive materials
for pollutants catalytic photodegradation was investigated using the terephthalic acid as the
probe molecule to study the quantum yield of hydroxyl radical (•OH) production [3]. The
photocatalytic degradation of a model pollutant molecule, phenol, was also investigated and
the results will be discussed.
Acknowledgements: M.C. Neves thank Fundação para a Ciência e Tecnologia (FCT) for the grant
SFRH/BPD/35046/2007. Authors thank FCT for financial support PTDC/CTM-NAN/113021/2009,
PEst-OE/QUI/UI0612/2011, Ciência 2007 Programme, FSE and POPH.
[1] Bavykin, D.V.; Wlash, F.C.; Titanate and Titania Nanotubes, synhtesis, Properties and Applications.
RSC Nanoscience & Nanothecnology. RSC Publishing: Cambridge, 2010.
[2] Kaneko, M.; Okura, I.; Photocatalysis, Science and Technology, Biological and Medical Physics
Series. Kodansha, Springer:Japan, 2010.
[3] Ishibashi, K.; Fujishima, A.; Watanabe, T.; Hashimoto, K.; J. Photochem. Photobiol A 2000 134,
139-142.
155
P11
Highly organized plasmonic nanoparticles:
Uniform plasmonic structures as SERS platforms
Nicolas Pazos-Perez1,*, Moritz Tebbe1, Ramon Alverz-Puebla2 and Andreas Fey1
1
Department of Physical Chemistry II, University of Bayreuth, 95440, Bayreuth, Germany.
2
ICREA - Catalan Institution for Research and Advanced Studies, Spain
*
[email protected]
Surface enhance Raman scattering (SERS) spectroscopy is a powerful ultrasensitive
technique which allows detection down to single molecule levels. The production of active
SERS substrates is based on the generation of hot spots created by plasmonic nanoparticles.
However, the controlled formation of these hot spots is still a challenge in order to produce
homogeneous and reproducible SERS intensities over large areas. On the other hand,
plasmonic nanoparticles are still in the focus of interest because of their potential use in
microelectronics, optical devices, and biomedical applications or to develop new metamaterial
properties. Their individual electromagnetic response is highly dependent on the specific size,
shape, and surrounding environment of the particles. At the moment, there are different
methods which allow us to fine tune the control over these parameters and thus, the materials
properties. However, the control over the collective behaviour of these individual particles and
their incorporation into new technological devices, relay on the ability to form reproducible
organized structures at large scales.
In this work we report novel methods to produce highly organized structures made of
plasmonic nanoparticles in a macro-scale range using a completely lithography-free approach.
Monolayers, supercrystals, and periodic linear arrays with tuneable width and spacing
between lines, were created via spin coating, confinement controlled drying, and their
combinations [1-4].
Furthermore, these structures,
were effectively use for sensing using
surface-enhanced Raman scattering
(SERS) spectroscopy showing the good
reproducibility of these structures among
big areas. This fact, make them perfect
candidates as quantitative ultrasensitive
SERS substrates due to the controlled
formation of hot spots. Which provide
high and uniform SERS enhancement
over extended areas.
Figure caption: Scanning electron microscopy (SEM) images of different nanoparticles organizations.
[1] Pazos-Perez, N., et al. Soft Matter 2011, 9, 4093.
[2] Mueller, M., et al. Langmuir 2012, 28, 9168-9173.
[3] Schweikart, A., et al. Chemical Science 2010, 1, 174.
[3] Pazos-Perez, N., et al.Langmuir 2012, 28, 8909.
[4] Pazos-Perez, N., et al., Angew. Chem. Int. Ed., DOI: 10.1002/anie.20120701.
156
P12
Ferromagnetic anisotropic nanostructures for aqueous metal ions uptake
Paula C. Pinheiro1,*, Daniela S. Tavares1, Ana L. Daniel-da-Silva1, Cláudia B. Lopes1,
Eduarda Pereira1, João P. Araújo2, Célia T. Sousa2, Tito Trindade1
1
Department of Chemistry-CICECO or CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
2
IFIMUP and IN, Department of Physics, University of Porto,4169-007 Porto, Portugal
*[email protected]
Water contamination by trace non-essential metals is an eco-toxicological hazard of
prime interest that has raised the attention of the scientific community. Nanotechnology offers
potential solutions for this environmental problem and in fact a number of nanomaterials have
been recently investigated as effective sorbents for water remediation and chemical analysis
[1]. Recently, we have been interested in developing colloidal magnetic nanoparticles for
water purification technologies, the so-called eco-nanomagnets, that could act as sorbents and
have the ability for magnetic removal. So far, we have already shown that dithiocarbamate
functionalized magnetite particles are highly efficient sorbents for uptake vestigial mercury
(II) ions from water by applying a relatively weak external magnetic field [2].
In this communication, we would like to present the latest results achieved with the
extension of the work to ferromagnetic anisotropic 1D nanomaterials (e.g. Ni nanowires), and
show the possibility of using this 1D nanomaterials, as magnetic sorbents. Ferromagnetic Ni
nanowires with cross sections within the range 40-60 nm were prepared using anodic
aluminium oxide as the template [3]. Surface modification strategies were then investigated in
order to confer thiolate moieties to these particles. The materials were fully characterized for
their morphological and magnetic properties.
Finally, a series of experiments were carried out
aiming to inquire about the efficiency of these
nanostructures as magnetic sorbents for mercury
(II) in water. The context of application of these
nanomaterials will be discussed based on
performance comparative studies with other
ferromagnetic sorbents, such as functionalized
magnetite particles, and their potential impact
on the environment.
Figure caption: SEM image of ferromagnetic nickel nanowires
Acknowledgements: The authors thank Fundação para a Ciência e Tecnologia (PTDC/CTMNAN/120668/2010, Pest-C/CTM/LA0011/2011, Pest-C/MAR/LA0017/2011),), FSE and POPH for
funding.
[1] Hernandez-Ramirez, O.; Holmes, S. M., J. Mater. Chem. 2008, 18, 2751–2761.
[2] Girginova, P. I.; Daniel-da-Silva, A. L.; Lopes, C. B.; Figueira, P.; Otero, M.; Amaral, V. S.; Pereira,
E.; Trindade, T., J. Colloid Interface Sci. 2010, 345, 234–240.
[3] Proença, M. P.; Sousa, C. T.; Ventura, J.; Vazquez, M.; Araújo, J. P., Electrochim. Acta 2012, 72,
215-221.
157
P13
PAMAM dendrimers exerted oxidative damage and structural alterations in
green algae and cyanobacteria
Ismael Rodea-Palomares1,*, Soledad Gonzalo2, Francisco Leganés1, Eloy García-Calvo3,
Francisca Fernández-Piñas1, Roberto Rosal2,3
1
Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid.
E-28049, Madrid, Spain
2
Departamento de Ingeniería Química, Universidad de Alcalá,
E-28871, Alcalá de Henares, Madrid, Spain
3
Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico,
E-28805, Alcalá de Henares, Madrid, Spain
*
[email protected]
The commercial applications of engineered nanoparticles (ENPs) have widely expanded
over the last years covering from biomedicine to industrial applications, with a subsequent
potencial increased release into the environment in the near future. Poly(amido amine) (PAMAM)
dendrimers are "dense star" polymers characterized by a high degree of structural homogeneity, a
highly- functionalized terminal surface and a symmetric increase of molecular weight and surface
functional groups with their increase in complexity (generation, G). Currently, PAMAM
dendrimers have important applications as drug carriers, but they have interesting perspectives in
an industrial process that implies a future increase of PAMAM dendrimer production and
subsequent release to the environment.
Algae and cyanobacteria are ecologically relevant organisms which are at the base of
aquatic food webs and have essential roles in nutrient cycling therefore being especially well suited
to study possible ecological impacts of nanomaterials. In our research group we have applied a
multi-method approach to understand the toxic mechanism of action of nanomaterials to these
organisms. Within this approach, physicochemical properties of nanomaterials on relevant
biological media were studied and linked with the biological information from the organisms. The
biological characterization of the organisms’ response to ENPs includes techniques such as flow
citometry, confocal microscopy and TEM microscopy which allows to link toxicity and metabolic
impairments with physiological end-points and structural alterations.
In the present work, the toxicity and possible mechanism of action of native –NH2
terminated and -NH-C-(CH2OH)3 functionalized PAMAM dendrimers from the generations (G)
G2, G3 and G4 were evaluated. NH2 terminated PAMAM exhibited a generation dependent
toxicity to both cyanobacteria and green algae (being G4 the most toxic one). -NH-C-(CH2OH)3
surface functionalized PAMAM G2 and G3 were not toxic but G4 presented a toxicity similar to
that of native G4 -NH2. Toxicity of –NH2 terminated PAMAM seems to be linked with a strong
increase of intracellular reactive oxygen species (ROS). The ROS induction is generationdependent being faster as generation increases. The internalization of –NH2 terminated PAMAM
was evaluated by generating fluorescent PAMAM-Alexa Fluor 488 conjugates. The uptake kinetics
of PAMAM conjugates was also generation dependent and surprisingly fast with more than 70% of
the total dendrimer being internalized in 10 min. Interestingly membrane damage and cytoplasmic
content extrusion phenomenon were observed linked with high ROS induction and intracellular
accumulation of –NH2 dendrimers.
Acknowledgements- This work was funded by Comunidad de Madrid grants S-0505/AMB/0321 and S2009/AMB/1511 (Microambiente-CM) and by the Spanish Ministry of Science and Innovation [grant
CGL2010-15675, sub-programme BOS].
158
P14
Steric Hindrance Induces Cross-like Self-assembly of Gold Nanodumbbells
Ana Sánchez-Iglesias1, Marek Grzelczak 1,2, Hamed Heidari Mezerji,3 Sara Bals,3 Jorge
Pérez-Juste,4 Luis M. Liz-Marzán 1,2,4,*
1
CIC biomaGUNE, Spain; 2Ikerbasque, Basque Foundation for Science, Spain; 3University of Antwerp,
Belgium; 4Universidade de Vigo, Spain;
*
[email protected]
In the formation of colloidal molecules, directional interactions are crucial for
controlling the spatial distribution of the building blocks. Anisotropic nanoparticles facilitate
directional clustering via steric constraints imposed by each specific shape, thereby restricting
assembly along certain directions.[1] We show that the combination of patchiness (attraction)
and shape (steric hindrance) allows assembling gold nanodumbbell building blocks into crosslike dimers with well-controlled interparticle distance and relative orientation (see Figure
below).[2] Steric hindrance between interacting dumbbell-like particles opens up a new
synthetic approach toward low-symmetry plasmonic clusters, which may significantly
contribute to understand complex plasmonic phenomena.
Figure caption: Polystyrene-stabilized nanoparticles undergo gradual clustering upon addition of water to
organic solvent. Encapsulation of clusters inside the polymeric micelles induces the crosslike
morphology.
[1] Glotzer, S. C.; Solomon, M. J., Nat Mater 2007, 6, 557–562.
[2]
Nano Lett. 2012, 12, 4380–4384.
-
-
, L. M.,
159
P15
Noble metal nanoparticles coated with mesoporous materials
Marta N. Sanz-Ortiz1,* and Luis M. Liz-Marzán1,2,3
1
Bionanoplasmonics Laboratory, CIC biomaGUNE, 20009 Donostia-San Sebastián, Spain.
2
Ikerbasque, Basque Foundation for Science, 48011 Bilbao, Spain.
3
Departamento de Química Física,Universidade de Vigo, 36310 Vigo, Spain.
*[email protected]
Metal nanoparticles exhibit physical and chemical behaviors that might radically
differ from those of the material in bulk. The control of size effects allows the fine tailoring of
the nanoparticles characteristics and confers them with a great number of potential
applications in many different fields. However, metal nanoparticles tend to aggregate causing
a detriment of their properties. Here we present the synthesis of inorganic (mesoporous silica
and zeolite crystals) and organometallic (metal-organic frameworks) coatings on noble metal
nanoparticles of different shapes and sizes. The coating not only avoids the aggregation of the
metal nanoparticles but it also facilitates the incorporation of new functionalities in the
system. The large surface ratio of mesoporous materials, the capability of hosting different
chemical species inside their pores and the chemical tunability of their surface, make metal
nanoparticles coated with these compounds ideal candidates for applications such as catalysis,
drug delivery, sensing and molecular targeting.
Acknowledgements: The research leading to these results has received funding from the European
Union's Seventh Framework Programme (FP7/2007-2013 under grant agreement n° 312184).
160
P16
Formation of plasmonic heterostructures via covalent bond chemistry
Ana Belén Serrano-Montes1,*, Marek Grzelczak1 and Luis M. Liz-Marzán1
1
Bionanoplasmonics Laboratory, CIC biomaGUNE,
Paseo de Miramón 182, 20009 Donostia-San Sebastián, Spain.
*
[email protected]
Surface-Enhanced Raman Scattering (SERS) is a powerful technique for chemical
and biomedical sensing, which has become a very important application of the field of
plasmonics. Metal nanoparticles, as a plasmonic nanobjects, exhibit suitable properties for
SERS enhancement.Specifically, branched nanoparticles, such as gold nanostars, are better
candidates for SERS than regular spherical particles. [1]This is because the nanostar serves as
a nanoscale antenna that increases the extinction cross section and the electromagnetic field
enhancements of the tip plasmons. [2]It is well known that particle-aggregation gives rise to
higher enhancement factors as compared to single particles because of hot spot formation.
[3]However, this conventional method of generating hot spots is hard to control
experimentally. We have explored covalent bond chemistry for the formation of complex
heterostructures consisting of gold nanostars and nanospheres. The results show that these
structures are promising candidates for biosensing applications.
[1] Rodriguez-Lorenzo, L.; Alvarez-Puebla, R. A.; García de Abajo, F. J.; Liz-Marzán, L. M., J. Phys.
Chem. C. 2010, 114, 7336-7340.
[2] Haom, F.; Nehl, C. L.; Hafner, J. H.; Nordlander, P., Nano Lett. 2007, 7, 735-732.
[3] Esenturk, E. N.; Walker, A. R. H., J. Raman Spectrosc. 2009, 40, 86-91.
161
P17
Various Strategies of Gold Nanostar Synthesis for SERS Applications
Amane Shiohara1, and Luis M. Liz-Marzán1.2.3,*
1
CIC BiomaGUNE, Paseo Miramón 182, 20009 Donostia-San Sebastían, Guipúzcoa, Spain
2
3
Universidade de Vigo, 36310 Vigo, Spain
*
[email protected]
Gold nanoparticles have been considered as strong candidates as nano-carriers or
sensing devices for various applications due to their Surface Plasmon Resonance. Recently the
research on anisotropic gold nanoparticles has received increasing attention due to their
unique characteristics. Especially star shaped nanoparticles are known to have higher
efficiency in Surface Enhanced Raman Spectroscopy (SERS) or Photothermal therapy
compared to nanoparticles of spherical shape due to the high electromagnetic fields generated
at their tips. However, it is still a challenge to establish the synthesis that can be biocompatible
and also can produce high quality nanostars. Previously several nanostar syntheses have been
proposed including seed-less growth and seed-mediated growth [1-5]. Recently Vo-Dinh et al.
discovered that silver ions can also be used
as the growth control factor to produce gold
nanostars in a surfactant free system [5]. In
this study, different systems to produce gold
nanostars were studied in terms of
biocompatibility, stability and further surface
modification for biomedical applications
such as photothermal therapy or SERS
detection. For the further step, silver coating
on the gold nanostars synthesized using
silver ions as a growth control factor was
studied to tune the Plasmon resonance band
and to enhance the SERS signals.
Figure caption: TEM image and UV-Vis spectrum of the
gold nanostars synthesized by silver ion assisted method.
Acknowledgements: This work has been funded by the ERC through Advanced Grant Plasmaquo.
[1] Xie, J.; Lee, J. Y.; Wang, D. I. C., Chem. Mater 2007, 19, 2823-2830
[2] Moukarzel, W.; Fitremann, J.; Marty, J. D., Nanoscale, 2011, 3, 3285-3290
[3] Kumar, P. S.; Pastoriza-Santos, I.; Rodoríguez-Gonzáles, B.; García de Abajo, F. J.; Liz-Marzán, L.,
Nanotechnol, 2008, 19, 015606
[4] Pallavicini, P.; Chrico, G.; Collini, M.; Dacarro, G.; Dona, A.; D´Alfonso, L.; Falqui, A.; DiazFerrnandez, Y.; Freddi, S.; Garofalo, B.; Genovese, A.; Sironi, L.; Taglietti, A., Chem. Comm.,
2011, 47, 1315-1317
[5] Yuan, H.; Khoury, C. G.; Hwang, H.; Wilson, C. M.; Grant, G. A.; Vo-Dinh, T., Nanotechnol., 2012,
23, 075102
162
P18
A simple method to prepare sorbents based on magnetite coated with siliceous
hybrid shells for the removal of non-essential metal ions from waters
Daniela S. Tavares1,*, Ana L. Daniel-da-Silva2, Cláudia B. Lopes1, Nuno J. O. Silva2, Vítor S.
Amaral2, João Rocha2, Eduarda Pereira1, Tito Trindade2
2
1
Department of Chemistry-CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
Department of Chemistry and Physics-CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
*
[email protected]
The pollution arising from the presence of metals in waste and surface waters
presents a severe problem due to the scarcity of drinkable water, and even at low
concentrations, mercury and other non-essential metal ions have become a serious
environmental problem due to their toxicity, persistent character in the environment and bioaccumulation and bio-amplification along the food chain. Consequently, in the last decades,
finding an effective solution to this problem has required the attention of the scientific
community [1]. Advances in nanoscale science and engineering are providing opportunities to
develop more cost effective and environmentally acceptable water purification processes [2].
This communication presents a new class of sorbents for water purification, based on
surface modified magnetite particles with amorphous silica shells incorporating thiolate
moieties. A common method to prepare these materials involves several synthesis steps
namely the insertion of carbon disulfide in aminic groups in order to functionalize the silica
surfaces with dithiocarbamate groups [3]. In this study we demonstrate that the surface of
magnetite particles may be chemically modified via a one-step hydrolytic co-condensation
process using tetraethoxysilane (TEOS) and a siloxydithiocarbamate (SiDTC) precursor in
alkaline medium. This functionalization strategy was applied both to amorphous silica (SiO2)
and magnetic (Fe3O4/SiO2) samples aiming at their use as metal-ion sorbents using magnetic
separation. Therefore the materials were characterized for their surface characteristics and
magnetic behaviour prior their application in water treatment experiments.
The new sorbents were tested for the removal of several metal ions, namely Hg(II),
Pb(II), Cd(II), Ag(I), Au(II) and Cu(II) from spiked water. For the particular case of Hg(II),
which is considered one of the most hazardous elements, the new sorbents exhibited high
sorption affinity that was interpreted in terms of an extensive chemisorption of the cations by
dithiocarbamate groups grafted at the siliceous domains. In less than 8 hours, only 2.5 mg of
material per litre of an Hg(II) solution with an initial concentration of 50 g L-1, decreased the
metal ion concentration to values lower than the guideline values for drinking water.
Moreover, further studies have shown that highly complex matrices, such as natural seawater
and natural river water, did not affect the removal capacity of the functionalized magnetic
particles.
Acknowledgements: The authors thank Fundação para a Ciência e Tecnologia (PTDC/CTMNAN/120668/2010, Pest-C/CTM/LA0011/2011, Pest-C/MAR/LA0017/2011), FSE and POPH for
funding.
[1] Borai, E. H.; El-Sofany, E. A.; T. N. Morcos, T. N., Adsorption 2007, 13, 95-104.
[2] Savage N.; Diallo, M. S., J. Nanopart. Res. 2005, 7, 331-342.
[3] Girginova, P. I.; Daniel-da-Silva, A. L.; Lopes, C. B.; Figueira, P.; Otero, M.; Amaral, V. S.; Pereira,
E.; Trindade, T., J. Colloid Interface Sci. 2010, 345, 234–240.
163
P19
Anisotropic Gold/PLGA Nanohybrids for Cancer Therapy and Imaging
A. Topete1,*, A. Cambón1, E. Vilar1, M. Alatorre-Meda1, S. Barbosa1, S. Carregal-Romero2,
W. Parak2 P. Taboada1, V. Mosquera1
1
Colloids and Polymers Physics Group, Physics Faculty, Universidad de Santiago de Compostela,
15782-Santiago de Compostela, Spain.
2
Biophotonik Group, Fachbereich Physisk, Phillips-Universität, D-35037, Marburg, Germany
*
[email protected]
The application of nanomaterials in drug delivery, imaging and therapy is an emerging
topic that has captured the interest of researchers from different disciplines, such as physics,
chemistry, biology and medicine [1]. This new field, known as nanomedicine, is a promising
discipline to achieve better results in different disease therapies and, in particular, in cancer
therapeutics, facilitating the translation from long and aggresive treatments to more effective and
safer treatments for patients. At this respect, the synthesis of nanoparticles (NPs) of noble metals
and polymers based on self-assembly together with top-down approaches have been employed to
obtain multifunctional systems capable to simultaneously combine two or more therapies and
imaging strategies in one single nanoconstruct [2]. In this work, we present the synthesis,
characterization and in vitro evaluation of an hybrid nanoplatform consisting of a poly (D,Llactide-co-glycolide) (PLGA) core and a gold nanoshell. PLGA NPs produced by the emulsionevaporation technique were co-loaded with the anticancer drug doxorubicine (DOXO) and iron
oxide magnetic NPS for magnetic resonance imaging and targeting. An anisotropic spiky gold
nanoshell was built over the PLGA cores to provide our nanosystem with NIR photothermal
therapeutic, optical imaging abilities [3], and photo-activable release of DOXO cargo. The
nanoshells were, in some case, additionally functionalized with targeting ligands (folic acid or
Herceptin) to ensure a receptor-mediated cell internalization process, or with a highly stable
conjugate of human serum albumin/indocyanine green to also use the nanoplatform as a potential
photosensitizer for photodynamic therapy (PDT) and NIR fluorescence imaging. Here, we present
the synthetic and bioa)
b)
c)
conjugation
routes,
structural and physicochemical characterization and in vitro
evaluation of the
nanoconstruct.
Figure caption: a) TEM image of gold/PLGA nanoshell; b) Confocal image of HeLa cells with
internalized nanoshells (green). c) Confocal images of laser triggered Dox release inside HeLa cells.
Acknowledgements: Authors thank Ministerio de Ciencia y Competitividad and Xunta de Galicia for
financial support. A. Topete thanks CONACYT, México, for his scholarship.
[1] Shi, D. Adv. Funct. Mater 2009, 19, 3356–3373.
[2] Ryu, J. H.; Koo, H.; Sun, I.C.; Yuk, S. H.; Choi, K.; Kim, K.; Kwon, I. C. Adv. Drug Deliv. 2012, 64,
1447-1458.
[3] Gobin, A. M.; Lee, M. H.; Halas, N. J.; James, W. D.; Drezek, R. A.; West, J. L. Nano Letters 2007,
7, 1929-1934.
164
P20
Thermal effects in loaded lipid nanoparticles dispersion and hybrid membranes
M. I. Vazquez1, J. Hierrezuelo2, J. M. López-Romero2, J. Benavente1,*
2
1
Dpto. Física Aplicada I. Facultad Ciencias. Universidad de Málaga, E-29071 Málaga, Spain
Dept. de Química Orgánica. Facultad Ciencias. Universidad de Málaga, E-29071 Málaga, Spain
*[email protected]
Encapsulation technologies are nowadays commonly used in pharmaceutical, medical
and cosmetic industries for the development of controlled-release delivery systems >1@. Many
therapeutically active molecules need to be encapsulated in a drug carrying system to prevent
the loaded drug from degradation but also to ensure their effective delivery in the biological
media. Solid lipid nanoparticles (SLNs) represent a class of particulate carriers for bioactive
organic molecules with advantages over other carrier systems which include good-to-high
loading capacity, low production costs and the possibility of large-scale industrial production.
LNPs can be prepared from natural sources by using biocompatible components, and their
properties can be tuned by controlling the nanoparticle shape, size and state of aggregation [2].
LNPs prepared using biocompatible components and with tuneable properties are of
significant interest, although their use is still limited due to stability problems during contact
with biological fluids, storage or administration. To overcome these limitations, functionalized
LNPs can be included in biocompatible supports, which offer an attractive route for the control
release of the active agents and their use as patches [3].
This paper shows temperature effects on water-dispersions of lecithin-triestearine
nanoparticles loaded with the sunscreen agent 2’,4’-dihydroxybenzophenone (DHB) and the
hybrid membrane obtained after their inclusions in a cellulosic (RC) support (DHBLNPs and
DHBLNPs/RC samples). Figure shows SEM and brilliant field microscope pictures for the
DHBLNPs (a) and the DHBLNPs-RC hybrid membrane. Our results show an increase in the
conductivity of the DHBLNPs with temperature independently of the nanoparticles percentage
in the solution, but a significant reduction in the case of the DHBLNPs/RC membrane, this
latter obtained from IS technique with dry samples. NaCl diffusional permeability (c = 0.1 M)
across the hybrid DHBLNPs/RC membrane for 20 t(ºC) 80 ºC follows the same tendency
than that found for the RC-support but values reduction around 25 %. These results indicate
the stability of the hybrid membrane for the range of temperature studied as well as under
osmotic pressure and aqueous environments.
(b)
Figure caption: (a) DHBLNPs SEM micrograph; brilliant field micrograph of DHBLNPs/RC membrane
Acknowledgements: CICYT (projects CTD/2011-27770 and CTQ/2010-17633) or financial support.
[1] Goodsell, D.S. Bionanotechnology; Wiley–Liss: New Jersey, 2004.
[2] Muchow, M.; Maincent, P.; Müller, R.H. Drug Dev. Ind. Pharm., 2008, 34, 1394–1405.
[3] Vázquez M.I., Peláez L., Benavente J., López-Romero J.M., Rico R., Hierrezuelo J, Guillén E.,
López-Ramírez, M.R. J. Pharmac. Sci. 2011, 100, 4815-4822.
165
P21
Control of the aggregation of primary nanocrystals during particle growth: from
smooth to rough magnetite particles
F. Vereda1, M. P. Morales2, B. Rodríguez-González3,4, J. de Vicente1 and
R. Hidalgo-Álvarez1,*
1
Biocolloid and Fluid Physics Group, Applied Physics Department, Faculty of Science, University of
Granada, E-18071 Granada, Spain
2
Materials Science Institute of Madrid, CSIC, Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
3
International Iberian Nanotechnology Laboratory, Braga 4715, Portugal
4
CACTI, Vigo University, E-36310 Vigo, Spain
*
[email protected]
We studied the morphology, internal structure and magnetic properties of magnetite
microparticles prepared by partial oxidation of ferrous hydroxide with KNO3 at different
excesses of Fe2+ ([Fe2+]Exc) We observed an obvious evolution of the surface morphology and
of the internal structure of the particles with [Fe2+]Exc: particles were relatively smooth
polyhedral single crystals at small [Fe2+]Exc, and became polycrystalline and developed a
surface roughness as [Fe2+]Exc increased. The different internal structures (and thus the
different surface morphologies) can be explained in terms of different mechanisms of growth.
Polyhedral particles are formed by direct crystal growth of the primary nanocrystals that
appear after the initial nucleation. The formation of the rough polycrystalline microparticles
involves the aggregation of
these primary nanocrystals,
followed by their direct
crystal growth in the radial
direction [1] (see diagram
below).
The
growth
mechanisms
are
qualitatively in agreement
with the evolution of
electrostatic
repulsion
between
the
growing
magnetite particles, as
inferred from the progress
of the system’s pH.
Figure caption: Schematic diagram (not to scale) of the different mechanisms that control particle growth
at increasing [Fe2+]Exc, resulting in the different surface morphologies shown in the micrographs. “Direct
CG” stands for “direct crystal growth”. Scale bars correspond to 1 Pm.
Acknowledgements: F. Vereda is grateful to the ‘Programa de reincorporación de doctores de la
Universidad de Granada’. This work was supported by MICINN MAT 2010-15101 and MAT201123641 projects (Spain), the European Regional Development Fund (ERDF) and the Junta de Andalucía
P10-FQM-5977, P10-RNM-6630 and P11-FQM-7074 projects (Spain). J. de Vicente and R. HidalgoAlvarez thank the financial support received from CEI-Biotic 20F12/16.
[1] Rodríguez-González, B.; Vereda, F.; de Vicente, J.; Hidalgo-Álvarez, R. J. Phys. Chem. C 2013, 117,
5367-5406.
166
P22
Synthesis of ZnO/Ag hybrid nanomaterials and study of their electrical
properties (Poster, Topic: Nanoparticles: organic, inorganic and hybrids)
German Vidal-Lopez1,*, Kelly Pemartin2, Conxita Solans2, Alfredo Morales-Sanchez1,
Margarita Sanchez-Dominguez1
1
Centro de Investigación en Materiales Avanzados (CIMAV S.C.), GENES-Group of Embedded
Nanomaterials for Energy Scavenging, Apodaca, 66600, MEXICO.
2
Instituto de Química Avanzada de Cataluña (IQAC-CSIC), and CIBER en Bioingeniería, Biomateriales
y Nanomedicina (CIBER-BBN), Barcelona, 08034, SPAIN.
*
[email protected]
In this work the synthesis of hybrid ZnO/Ag nanomaterials by the microemulsion
reaction method has been investigated. The aim of the research is to synthesize different ZnO
morphologies and NPs size by varying the conditions of the method and by adding silver on
ZnO in order modulate the electrical properties. Two strategies were used for the preparation
of the hybrid ZnO/Ag nanomaterial. The first strategy consists of two steps, first a reaction is
carried out by using an oil-in-water (O/W) microemulsion containing an organometallic
precursor of Zn in the oil phase and adding a precipitating agent (base) in order to obtain ZnO
nanoparticles. The second step consists in the synthesis of Ag nanoparticles by the water-in-oil
(W/O) microemulsion method, followed by addition of ZnO nanoparticles synthetized
previously by the oil-in-water microemulsion method. The second, one-pot strategy consists in
the synthesis of Ag nanoparticles in an W/O microemulsion, and then a Zn precursor is added
to the aqueous phase followed by precipitation of ZnO nanoparticles using a second
microemulsion containing a base in the aqueous phase. In general for the different materials
synthesized, the X-ray diffraction (XRD) analysis corresponds with hexagonal crystalline
structure for ZnO and a cubic crystalline structure for Ag. The SEM micrographs have
demonstrated that the structure obtained depends on the base used for precipitation. Different
ZnO self-assembled nanostructures were obtained: raspberry[1], flowers[1] and bow-like. These
self-assemblies are formed by individual nanoparticles of ZnO. On the other hand, the XRD
patterns have demonstrated good chemical compatibility between the two materials at a
concentration of 5% of Ag on ZnO, since no chemical change was observed upon their
combination; however in order to obtain this result, the sequence in the reaction method and
the reaction conditions were critical. For the electric measurements a device was fabricated.
The hybrid nanomaterial was incorporated into a polymeric matrix. Then a layer of the
polymeric matrix was deposited onto an ITO-coated PET substrate by spin-coating followed
by deposition of the metallic contacts. It was demonstrated that the electrical properties of the
hybrid nanomaterial can be modulated as a function of the method used to synthesize the
hybrid Ag/ZnO nanomaterial with different structures.
Acknowledgements: We acknowledge CONACYT for the financial support (CB project No. 166649) as
well as Josué A. Aguilar, Cesar Leyva and Nayeli Pineda (CIMAV, S.C.) for their technical assistance.
[1] Permartin, K.; Solans, C.; Vidal, G.; Sanchez, M., Chem. Lett. 2012, 41, 1032-1034.
167
P23
Design of a dual nanostructured lipid carriers formulation based on
physicochemical, rheological and mechanical properties
Carla Vitorino1, Luís Alves2, Filipe E. Antunes2, João J. Sousa1, Alberto A. C. C. Pais2,*
1
Centro de Estudos Farmacêuticos (CEF), Faculty of Pharmacy, University of Coimbra, Portugal
2
Department of Chemistry, University of Coimbra, Portugal
*
[email protected]
The synergy between nanostructured lipid carriers (NLC) and chemical penetration
enhancers have been investigated as a promising strategy to effectively deliver drugs through
the skin. In the present work, focus is given on the study of the interaction of limonene,
ethanol and Carbopol Ultrez®10NF as gelling agent with a co-encapsulating NLC dispersion,
containing both olanzapine and simvastatin. The analysis is based on the rheological,
mechanical and physicochemical properties.
Only a small increase in the mean NLC particle size was observed when the
temperature was raised up to 50ºC. Ethanol generally tended to increase NLC mean particle
size, while the more hydrophobic limonene did not impact on this parameter. A swelling
mechanism is probably responsible for the alteration with the former, hypothesis corroborated
by the observed increase in the steady viscosity. The inclusion of the gelling agent resulted in
a further increase in size. This can be attributed to carbomer bridging nanoparticles and
causing some degree of particle aggregation. Rheological measurements indicated that the
viscosity of the neat carbopol hydrogel was significantly reduced by the addition of enhancers
and, to a higher extent, by the further inclusion of the NLC. A change in the bulk solution
properties due to a more apolar medium can be pointed out as explanation. A hydrophobic
polymer/nanoparticle interaction coupled with surfactant/polymer H-bonding provides the
rationale for the NLC effect. Texture analysis, comprising compressibility, hardness,
adhesiveness, elasticity and cohesiveness measurements, provided a complementary
characterization, relevant for product
performance and corroborated the trends
found in the rheological measurements.
The inclusion of enhancers and polymer
gelling agent largely contributed to the
physicochemical stability of the NLC
formulation, as revealed by the low
transmission profiles and more negative
zeta potential values.
Figure caption: Rheological, mechanical and stability analysis of an optimized NLC formulation.
Acknowledgements: CSV acknowledges financial support through grant SFRH/BD/41536/2007 from
FCT (Fundação para a Ciência e Tecnologia, Portugal). We acknowledge Dr. Pedro Prazeres from
GmBH (Dias de Sousa) for the availability of LUMiFuge centrifuge.
[1] Vitorino, C.; Almeida, J.; Gonçalves, L. M.; Almeida, A. J.; Sousa, J. J.; Pais, A. A. C. C., J.
Controlled Release 2013, 167, 301.
168
P24
Thermodynamic study of the interaction between 5,10,15,20-Tetrakis-(N-methyl4-pyridyl)porphyrin tetraiodine and sodium dodecyl sulfate:
a conductometric study
C. M. R. Almeida, R. F. P. Pereira, Bruno F. O. Nascimento, M. Pineiro and A. J. M. Valente*
*
[email protected]
Porphyrin defines an enormous class of compounds with diverse applications. The
photochemical and catalytic properties of the tetrapyrrolic macrocycle, which form the
porphyrin core, could be modulated trough the insertion of different substituents at the
periphery or through the coordination with several metals, making them appropriate for such
different applications as photodynamic therapy of cancer or photovoltaic devices.[1]
5,10,15,20-Tetrakis-(N-methyl-4-pyridyl)porphyrin tetraiodine (1) is a water soluble
porphyrin, highly symmetrical , with four coordination sites that compared with di- and tricationic ligands, are relatively rarely used as molecular building blocks [2].
N
NH
N
N
N
HN
N
N
1
In this communication, we report the effect of 5,10,15,20-Tetrakis-(N-methyl-4pyridyl)porphyrin tetraiodine on the micellization properties of sodium dodecyl sulfate. It has
been found that interaction between SDS and (1) occurs at concentration considerably below
the surfactant cmc. The aggregates have a stoichiometry similar to that expected by charge
neutralization. On the contrary to results obtained for interactions between trivalent metal ions
and SDS [3], these aggregates do not redissolve in the presence of an excess of SDS. The
effect of (1) on the thermodynamic of SDS micellization will also be discussed.
[1] Chou, J.-H.; Nalwa, H. S.; Kosal, M. E.; Rakow, N. A.; Suslick, K. S. in The porphyrin handbook,
Vol. 6 (Eds.: K. M. Kadish, K. M. Smith, R. Guilard), Academic Press, San Diego, 2000.
[2] DeVries, D. L.; Choe, W. J. Chem. Crystallogr. 2009, 39, 229-240.
[3] Pereira, R. F. P.; Tapia, M. J.; Valente, A. J. M.; Evans, R. C.; Burrows, H. D.; Carvalho, R. A. J.
Colloid Interface Sci. 2011, 354, 670-676
169
P25
Rheological studies of unmodified cellulose solutions based on new
promising alkali solvent systems
Luís Alves1, Carolina Costa1, Filipe Antunes1,*, Bruno Medronho2 and Björn Lindman1
1
Faculty of Sciences and Technology, Institute for Biotechnology and Bioengineering, Centre of
Genomics and Biotechnology (IBB/CGB), University of Algarve, Campus de Gambelas, Ed. 8, 8005-139
Faro, Portugal
*
[email protected]
2
Cellulose has many industrial applications and is the most used biopolymer in the
world. The estimated amount of cellulose and derivatives used each year, exceed 75 million
tons[1]. Many important cellulose applications involve, at some stage, dissolution and, for
different reasons, this task is normally complicated. Traditional dissolution methods have
important limitations especially allied to environmental and human health issues and thus
there is a growing need to replace these severe processes.
The development of cheaper, environmentally and human friendly alternatives,
without toxic compounds, to the solvents used nowadays is thus of great interest in the
industrial circle.
In this work, we have develop new promising alkali based solvents, showing good
dissolution ability of cellulose with reasonably high molecular weight. The phase behavior
and rheological properties were studied as a function of temperature, composition,
concentration and it was found that the viscosity of solutions increases both with cellulose
content and temperature decrease. Gelation, usually observed in cellulose solutions, represents
a problem in industrial applications making the spinning process of the fibers very difficult.
Therefore, we have also evaluated the time dependent gelation phenomenon. The solutions
were quite stable and no gelation was found using these alkali based solvent systems. These
cellulose solutions are a very promissory for fiber spinning. Films could be precipitated from
cellulose solutions using simple coagulations systems such as water, ethanol or acidic
solutions.
[1] Kirk-Othmer, Kirk-Othmer Encyclopedia of Chemical Technology. 5th Edition ed.; John Wiley &
Sons, Inc.: 2004; Vol. 5.
170
P26
Nanostructuring conjugated polyelectrolytes in tetraethylene glycol
monododecyl ether/water liquid crystals
Hugh D. Burrows1, *, Matti Knaapila2, Sofia M. Fonseca1, Beverly Stewart1, Mika Torkkeli3,
Jan Perlich4, Swapna Pradhan5 and Ullrich Scherf5
1
Departamento de Química, Universidade de Coimbra, Portugal.
Physics Department, Institute for Energy Technology, NO-2027 Kjeller, Norway.
3
Department of Physics, FI-00014 University of Helsinki, Finland.
4
DESY Photon Science, D-22607 Hamburg, Germany
5
Macromolecular Chemistry Group, Bergische Universität, D-42119 Wuppertal, Germany
*
[email protected]
2
Conjugated polyelectrolytes (CPEs) are an important group of materials, with
applications ranging from light emitting devices, photovoltaic cells to chemical or biological
sensors. Their aqueous solubility favours processing from solution using methodologies such
as ink-jet printing, and may also facilitate self-assembly. Fluorene based systems are excellent
candidates for many of these applications because of their blue emission, high fluorescence
quantum yield and possibility of modification to make them good charge carriers [1].
Although they tend to cluster in water, we have shown that it is possible to obtain
homogeneous solutions having isolated conjugated polymer chains by using non-ionic
oxyethylene based surfactants, CmEn [2]. These form cylindrical micelles, which grow upon
increasing surfactant concentration to give long, wormlike structures. In addition to micellar
solutions, non-ionic surfactants form a wide variety of liquid crystalline phases with water [3].
We report a combined fluorescence spectroscopy and small angle and grazing incidence X-ray
scattering study on the anionic poly[9,9-bis(4-sulfonylbutoxyphenyl)fluorene-2,7-diyl-2,2'bithophene] (PBS-PF2T) in aqueous 25% tetraethylene glycol monododecyl ether (C12E4) in
bulk and thin films. These indicate that PBS-PF2T is present as isolated chains and that this
mixture follows similar phase behaviour to the pure surfactant, including a micellar phase
below about 20 oC, a lamellar phase in between about 20 and 70 oC and a proposed
coexistence of water and liquid surfactant solution above 70 oC. Molecular dynamics
simulations suggest the CPE is localised in the surfactant head group region, with the ionic
chains pointing into the water domains.
S
S
O
NaO3S
n
O
PBS-PF2T
SO3Na
Structure of PBS-PF2T
[1] Scherf, U.; Neher, D., Eds., Polyfluorenes, Adv. Polym. Sci. 2008, vol.212.
[2] Burrows, H.D., Knaapila, M.; Fonseca, S.M., Costa, T., Aggregation Properties of Conjugated
Polyelectrolytes. In “Conjugated Polyelectrolytes. Fundamentals and Applications in Emerging
Technologies”, ed. B. Liu, G. C. Bazan, Wiley-VCH, Weinheim, 2013; pp 127-167.
[3] Holmberg, K., Jönsson, B., Kronberg, B., Lindman, B. Surfactants and Polymers in Aqueous
Solution, Wiley, Chichester, 2nd Edn., 2003.
171
P27
A novel approach to the development of unmodified cellulose solvents
Carolina Costa1, Luís Alves1, Filipe Antunes1,*, Bruno Medronho2, M. Graça Miguel1 and
Björn Lindman1
1
Faculty of Sciences and Technology, Institute for Biotechnology and Bioengineering, Centre of
Genomics and Biotechnology (IBB/CGB), University of Algarve, Campus de Gambelas, Ed. 8, 8005-139
Faro, Portugal
*
[email protected]
2
Cellulose is the most abundant natural polymer in the world and has numerous
applications. Some important industrial applications involve a dissolution step but this is
normally challenging since cellulose is difficult to dissolve. However, a large number of
solvents have been developed in the last years but, in general, most of them are limited to lab
scale applications due to, for instance, cost and environmental issues. Thus, there is a need to
find “greener” alternatives. It is clear that for the industry sector, the development of cheaper
and environmentally friendly alternatives to the solvents used nowadays is thus of great
interest.
Promising alkali based solvents has been developed in this work. Good results regarding
cellulose dissolution with reasonably high molecular weight were obtained. Additionally,
polarized light microscopy and scanning electron microscopy were used to infer about the
solvent quality. It was found that during cellulose regeneration (i.e. coagulation in “antisolvent” such as an acidic aqueous medium) a crystal rearrangement seems to occur. The
amount of crystals appeared to increase after regeneration. Finally, transparent films could be
precipitated from cellulose solutions using simple coagulations systems such as water and
ethanol.
172
P28
Water-Borne Pressure Sensitive Adhesives based on Renewable Protic Ionic
Liquids
Ana M. Fernandes1,2,*, Monica Moreno2, Ali Adboudzadeh2,
Raquel Gracia2, Maria J. Barandiaran2, David Mecerreyes2,3
1
Polytechnic Institute of Bragança, Portugal.
POLYMAT, University of the Basque Country (UPV/EHU),
Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastian, Spain.
3
Ikerbasque, Basque Foundation for Science, E-48011 Bilbao, Spain.
*
[email protected]
2
Nowadays, several arguments account for the great potential of renewables resources
as an alternative for the production of polymeric materials [1]. The high price and future lack
of fossil fuels are creating doubts about the sustainability of the current polymer industry.
Carboxylic acids are widespread in nature and important raw materials for the synthesis of a
number of industrial polymers. For these reasons, there is a growing interest in the use of
natural products for the development of polymers that match or even improve the performance
of the current oil-based polymeric materials [2].
In this work, we extended our initial research in the development of protic polymeric
ionic liquids [2-3], which incorporate renewable carboxylic acids. The application of this
chemistry, to develop green odorless polymer latexes, was investigated based on new latexes
obtained by emulsion polymerization of dimethylaminoethyl methacrylate and renewable
dicarboxlylic acids. The synthetic results and the adhesion test carried out will be presented.
Figure caption: Incorporation of carboxylic dimer acids into ionic polymers.
Acknowledgements: The financial support of Basque Government and MINECO through projects
MAT2010-16171 is acknowledged.
[1] R. Vendamme, K. Olaerts, M. Gomes, M. Degens, T. Shigematsu, W. Eevers, Biomacromolecules,
2012, 13, 6, 1933-44.
[2] M. Moreno, M.A. Aboudzadeh, M.J. Barandiaran, D. Mecerreyes, J. Polym. Sci. Part A Polym.
Chem. 2012, 50, 6, 1049-1053.
[3] D. Mecerreyes, Progr. Polym. Sci., 2011, 5, 7.1629-1648.
173
P29
Biomimetic Triblock Copolymer Membranes:
From aqueous solutions to solid supports
A. González-Pérez1, V. Castelletto2, I. Hamley2, A. Topete3, E. Villar-Alvarez3, N. González3,
A. Cambón3, S. Barbosa3, P. Taboada3, V. Mosquera3
1
Membrane Biophysics Group, Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100
Copenhagen Ø / Denmark.
2
School of Chemistry, Food Science and Pharmacy, University of Reading, Whiteknights, Reading RG6
6AD, UK
3
Department of Condensed Matter Physics, Faculty of Physics, 15782 Campus Sur, University of
Santiago de Compostela, Santiago de Compostela, Spain
In the present work, the preparation of biomimetic triblock copolymer membranes
formed by a triblock copolymer of poly(dimethylsiloxane) (PDMS) and poly(2methyloxazoline) (PMOXA), PMOXA7-PDMS60-PMOXA7 (type ABA, where the subscripts
denote the block length) in aqueous solution and their deposition into solid supports is studied.
The self-assembly structures of the ABA in aqueous solution was investigated by using optical
microscopy, dynamic light scattering, electron microscopy (EM) and SAXS, as was found to
be concentration-dependent, this opens up additional possibilities to use organic solvent-free
membranes as a support for membrane protein incorporation. In particular, spherical and
tubular polymersomes were found to coexist at the highest concentrations investigated, the
relative population of which depends on the polymer concentration. The mechanism of
deposition onto solid supports (mica and glass) was elucidated by using atomic force
microscopy (AFM). The deposition results in the formation of a uniform defect-free
membrane at suitable polymer concentrations. The interaction between polymeric membranes
and solid substrates become a key step in the development of new solid-supported membranes
containing embedded membrane proteins.
174
P30
Spectroscopic study of the interaction of Hecameg with Bovine Serum Albumin
and its effect on the protein conformation
J. M. Hierrezuelo1, B. Nieto-Ortega2 and C. Carnero-Ruiz1,*
1
Department of Applied Physics II, University of Málaga, 29071Málaga. Spain.
Department of Physical Chemistry, University of Málaga 29071Málaga. Spain.
*
[email protected]
2
Ionic surfactants interact more effectively with proteins than nonionic surfactants,
promoting often unfolding and, consequently, protein structure alterations. However, there are
applications that require preservation of protein functionality and the use of nonionic
surfactants is preferred in these cases. Among these applications, the isolation and purification
of membrane proteins and the stability of protein-based pharmaceutical formulations, occupy
a prominent place. In order to assess the potential use of the nonionic surfactant 6-O-(NHeptylcarbamoyl)-methyl--D-glucopyranoside (Hecameg), belonging to the alkyl
polyglycosides family, as a stabilizing agent of proteins, we have studied its interaction with
the protein Bovine Serum Albumin (BSA), at pH 7.4 and 25 ºC, using spectroscopic
techniques such as steady-state and time-resolved fluorescence and circular dichroism (CD).
The changes in the intrinsic fluorescence spectra of BSA induced by the surfactant addition
indicate a weak interaction between surfactant and protein. These data allows us to obtain the
binding curve (the insert of Figure), estimated from the fraction of protein occupied by
surfactant, , which suggests that Hecameg binds in a sequential manner to protein. At low
surfactant concentration, slightly increases with the surfactant concentration, indicating an
initial non-cooperative binding process where the hydrophobic interactions are probably
predominant. From a certain surfactant concentration, it is seen an abrupt increase of with
the surfactant concentration, until reaching a plateau. This second region clearly reflects a
cooperative binding scenario, which finally
leads to the saturation binding region.
1.00
5.5x10
Similar conclusions were extracted from
T
0.75
time-resolved fluorescence studies, which
5.0x10
also reflect a stepwise mechanism, whereby
0.50
the surfactant first occupies the hydrophobic
0.25
sites of the protein inner cavity and then,
4.5x10
through
a
cooperative
mechanism,
0.00
condensates onto the surface hydrophobic
1
10
4.0x10
sites of the protein. Finally, CD studies
[Hecameg] (mM)
indicate that the secondary structure of BSA
is not appreciably perturbed by the
3.5x10
0
5
10
15
20
25
30
35
40
surfactant binding over the concentration
[Hecameg] (mM)
range studied.
Fluorescence intensity (a.u.)
3
3
3
3
3
Figure caption: Intrinsic fluorescence of BSA as a function of the total surfactant concentration in
aqueous buffer solutions of pH 7.4 and 25 ºC. Inset: binding curve, showing the fraction of a protein
molecule bound by surfactant, , as a function log of the total surfactant concentration.
Acknowledgements: This work has been financially supported by the “Consejería de Innovación,
Ciencia y Empresa de la Junta de Andalucía” (Project P07-FQM-02762).
175
P31
Novel Structural Changes During Temperature-Induced Self-Assembling and
Gelation in Aqueous solutions of the Copolymer PLGA1170-PEGn-PLGA1170
Neda Khorshid1, Kenneth Knudsen2, Sverre Arne Sande3, and Bo Nyström1,*
1
2
Department of Physics, Institute for Energy Technology, Kjeller, Norway.
3
Department of Pharmaceutics, School of Pharmacy, University of Oslo
*
[email protected]
It is well established that certain polymers undergo conformational changes in response to
changes in temperature, pH, magnetic field, electrical field, or the wavelength of light. In one type of
stimuli-responsive polymer, thermogel polymers, the polymer aqueous solution undergoes sol-to-gel
transition as the temperature increases. Drugs or cells can be mixed into the polymer aqueous solution
when it is in its lower viscosity solution state. After injection of the solution into a target site, heating
prompts the formation of a hydrogel depot in situ, which can then act as a drug releasing system or a cell
growing matrix.
In this presentation, we have employed small-angle neutron scattering (SANS) technique to
study temperature-induced structural transitions of water-soluble triblock copolymers of the type [1,2]
poly(D,L-lactic acid-co-glycolic acid)1170-block-poly(ethylene glycol)n-poly(D,L-lactic acid-co-glycolic
acid)1170 (PLGA1170-b-PEGn-PLGA1170). The length of the PEG spacer assumes two values (n =1000 and
n =1500) and this gives rise to fundamental different structural features of the polymer complexes in
dilute and semidilute concentration regimes at different temperatures.
The length of the PEG spacer has dramatic implications for the structures formed in dilute
aqueous solution (1 wt %). For the longest PEG chain (n = 1500), temperature-stable spherical micelles
are created. These micelles are probably stabilized due the fact that the PEG chain is long enough to turn
back on itself so that both PLGA-ends of one chain can be incorporated into the same micelle. For the
PEG block with n = 1000, the micelles cannot be stabilized like that with n =1500, and the equilibrium
conformation at low temperature (10 oC) is an elongated micelle (prolate) with the PEG chains extending
into solution. At high temperatures, these disk-like particles will easily aggregate and start to sediment at
the highest temperature of measurement.
In semidilute solutions (20 wt%) of the copolymer with n=1000, intermicellar interactions with
the formation of core-shell structures is observed at 10
o
C. At 20 oC, the correlation peak in the SANS
scattering curve disappears, because a gel network is
formed; at 30 oC rod-like entities are created (cylinder
length: 34 nm and radius 6 nm) and at 40 oC, closepacking (hexagonal packing) of micelles to thick
“cylinders” (d = 16 nm) occurs (see Figure 1). For the
copolymer with n=1500, similar scattering profiles
evolve but in this case flower-like micelles can be
formed and they are more stable than those formed for
n = 1000, and the gel network is formed 40 oC as
compared with 20 oC for n=1000. These novel
structural features for this type of copolymer in
aqueous solution have not been reported previously.
Figure caption: SANS scattering data for a 20 wt% aqueous solution of PLGA1170-b-PEG1000-PLGA1170 at different
temperatures and the change from spherical micelles to cylindrical micelles and the formation of gel at 20 oC.
[1] Lee, D. S.et. al. Macromol. Rapid Commun. 2001, 22, 587-592.
[2] Chen, S. Int. J. Pharm. 2005, 288, 207–218.
176
P32
Synthesis and mineralization of a polymeric network using the reaction diffusion
method.
Enrique Lopez-Cabarcos*, Yousof Ramadan, Jorge Rubio-Retama
Department of Physical-Chemistry II, Faculty of Pharmacy, Complutense University of Madrid,
Plaza Ramón y Cajal 2, 28040 Madrid, Spain.
*
[email protected]
The formation of precipitates in a gel after the meeting of two reaction fronts that
diffuse from opposite sides enables to relate scientific fields that are normally separated such
as gel structure, dynamics of reaction fronts, crystal growth in gels, nanoparticles synthesis,
and biomineralization. Even though this is an old research subject, a new approach to the
phenomenon was taken recently when gels started to be used as a model to study
biomineralization since many mineralization processes take place in gelling environments [1].
Most of the research in this field was performed using physical gels such as gelatin, agarose,
silica, starch, polyvinyl alcohol) hydrogels [2-4], and only a few studies were done with
chemical gels [5].
We have selected hydrogels based on methacrylates because they are biocompatible,
non toxic, non-immunoreactive and their porosity can be controlled by the amount of crosslinker. We have synthesized and characterized a new copolymer matrix formed by
polyethylene glycol methyl ether methacrylate and 2-dimethylamino ethyl methacrylate,
crosslinked with N,N-methylenebisacrylamide. A piece of the swelled gel is inserted in the
middle of a plastic tube connected to both sides with silicone tubes that ended each one in a
bottle containing an aqueous solution of the corresponding reactant. The reactants are aqueous
solutions of CaCl2 (20 mM) and Na2HPO4 (20 mM)
and the temperature was around 20 ºC. In Fig.1 we
can see a SEM micrograph of the calcium phosphate
particles (brushite) formed within the gel. The
distribution of particle size is rather homogeneous
with dimensions between 2 and 3 microns. The TEM
picture of the calcium phosphate microparticle shows
that is formed by nanocrystals of brushite
(CaHPO4·2H2O). The gel-calcium phosphate
composite might have application in dentistry as
bone regeneration biomaterial.
Figure caption: SEM pictures of the calcium phosphate microparticles formed with the gel
[1] Hanying, L.; Huolin, L. X.; Muller, D. A.; Lara, A. Science 2009, 326, 1244-1277.
[2] Lopez-Cabarcos, E.; Kuo, C. S.; Scala, A.; Bansil, R. Phys. Rev. Lett. 1996, 77, 2834-2837
[3] Sander, C.G.; Leeuwenburgh, C.; Junichiro, J.; Wang, H.;. Yamamoto, M; Jansen, J. A.; Tabata, Y.
Biomacromolecules 2010, 11, 2653–2659
[4] Sohier, J.; Corre, P.; Weiss, P.; Layrolle, P. Acta Biomaterialia 2010, 6, 2932–2939,
[5] Yokoi, T.; Kawashita, M.; Kikuta, K.; Ohtsuki, C. Materials Sci. Eng. C 2010, 30, 154–159
177
P33
Adsorption of polyelectrolyte-surfactant mixtures of cosmetic interest
Sara Llamas1, Ramón G. Rubio1,*, Francisco Ortega1, Nawel Baghdadli2, Gustavo Luengo2,
Colette Cazeneuve2
1
Departamento de Química Física I, Facultad de Química, Universidad Complutense, 28040-Madrid,
Spain. 2L’Oréal Research, Aulnay-sous-Bois, France.
*
[email protected]
The interactions between polymers and surfactants in aqueous solution have attracted
a growing interest in colloidal science because of their major role in a wide range of industrial
applications, among which cosmetic applications stand out. This mixtures form
supramolecular structures that have unusual mechanical, optical and electrical properties that
may help to make better formulations in hair-care products.
The interactions between polymers and surfactants of opposite charge are quite strong
and can induce complex formation often resulting highly ordered structures [1]. Both
electrostatic interactions (between the charged components) and hydrophobic interactions (e.g.
between the polymer backbone and the alkyl chains of the surfactant) are important in driving
the self-assembly of the molecules to form ordered structures. As a consequence, these
systems show two characteristic points as the surfactant concentration is increased: the critical
aggregation concentration (c.a.c.) and the critical micelle concentration (c.m.c.) [2].
The applications under discussion involve the adsorption and deposition of
complexes onto a negatively charged surface (model surfaces that simulate that of the hair
fibers). In this work, mixtures of cationic polyelectrolytes with anionic and zwitterionic
surfactants has been studied at the air-liquid and liquid-solid interfaces. Formation and
adsorption of complex have been studied by surface tension, potential, dynamic light
scattering, quartz-crystal microbalance, and ellipsometry measurements. The results show that
there is a strong synergistic effect between the polyelectrolyte and the surfactant in decreasing
the air/liquid surface tension, leading to an important decrease of the c.m.c. The adsorption at
the solid/liquid interface has shown that the addition of the surfactant improves pure
polyelectrolyte’s adsorption properties, and the ability of the polymer layer to capture water.
The last characteristic is important for improving the tribological properties of the hair fibers,
and therefore the performance of the conditioner product.
Acknowledgements: This work has been supported by L’Oréal Research.
[1] K. Kogej, Adv. Colloid Interface Sci. 2010, 158, 68-83.
[2] C. D. Bain, P. M. Claesson, D, Langevin, R. Meszaros, T. Nylander, C. Stubenrauch, S.Titmuss, R.
Von Klitzing, Adv. Colloid Interface Sci. 2010, 155, 32-49.
178
P34
Molecular dynamics simulations of surfactant micelles
Victoria I. Martín*, Luis Javier Álvarez1 and María Luisa Moyá
1
Laboratorio de Simulación, Instituto de Matemáticas, Unidad Cuernavaca, Universidad Nacional
Autónoma de México. A. P. 273-3. Admon. 3, 62251 Cuernavaca, Morelos, México
*
[email protected]
In a previous work the two single-chain surfactants N-benzyl-N,N-dimethyl-N-(1dodecyl)ammonium bromide (PH12)
and N-cyclohexylmethyl- N,N-dimethyl-N-(1dodecyl)ammonium bromide (CH12) were prepared and characterized [1]. The aggregation
numbers estimated for these two surfactants seemed too low when compared to those of related
single-chain surfactants. This result was investigated with the help of 1H NMR ROESY
measurements (see Figure), which point out that the phenyl and cyclohexyl rings present in the
head groups of the surfactants are bent towards the micellar interior in order to avoid contact with
water. With the goal of further investigating this point, molecular dynamics, MD, simulations were
carried out. The effective charge values were determined through periodic Hartree–Fock
calculations. Water is treated using a single point charge model (SPC), consisting of a tetrahedral
arrangement with an OH distance of 0.1 nm, with point charges on the oxygen and hydrogen
positions of -0.82 e and +0.41 e respectively. We also used a Lennard-Jones interaction potential
between oxygen. All calculations were carried out with the Gromacs package using the
implemented force field that includes Lennard-Jones interactions plus coulombic ones when
necessary. Molecular mechanics energy minimizations were carried out in order to obtain
reasonable initial configurations for the molecular dynamics simulations. The MD runs were
performed at constant temperature in the NVT ensemble. Each MD schedule proceeded as follows:
first, a solvent relaxation run of 500 ps; second, a temperature controlled run with Berendsen’s
thermostat at 300 K for 5 ns and third, a statistics and accumulation production run of another 5 ns.
Results indicate that the rings are bent toward the micellar interior in agreement with the
observations.
Figure caption: Partial ROESY spectrum of an aqueous micellar solution of [PH12]=0.01 M. T=303 K.
Acknowledgments. This work was financed by the DGCYT (grant CTQ2009-07478), the FEDER funds and
[1] Martín, V, I.; Rodríguez, A.; Graciani, M. M.; Robina, I.; Carmona, A.; Moyá, M. L. J. Colloid Interface
Sci. 2011, 363, 284-294.
179
P35
Synthesis and physicochemical characterization of alkanedyilbis(dimethyldodecylammonium) bromide, 12-s-12,2Br-, surfactants with
s=7, 9 ,11 in aqueous medium
Victoria I. Martín*, Amalia Rodríguez, Alfredo Maestre and María Luisa Moyá
*
[email protected]
lncmc
lncmc
Menger et al. and Zana et al. have prepared and characterized the didodecyl dicationic
dibromide dimeric surfactants with different methylene spacer lengths, 12-s-12,2Br-, with s=2, 3, 4,
5, 6, 8, 10, 12, 14 and 16 [1,2]. Our group has been interested in the study of micellar growth in 12s-12,2Br- aqueous micellar solutions in the absence as well as in the presence of various additives
such as alcohols, organic polar solvents and monomeric surfactants. An increment in the dimeric
surfactant concentration causes a morphological transition from spherical to elongated micelles and
the [surfactant] where the change in size and shape of the micelles occur is called the second cmc,
C*. It was found that 12-s-12,2Br- dimeric surfactants with an even number of methylenes in the
spacer show smaller C* values than those with an odd number of –CH2- units in the spacer [3].
Besides, an endothermic enthalpy change accompanying the morphological transition was found
for even spacers whereas an
exothermic enthalpy change was
found for odd spacers. In order to
-13.0
investigate this point further, the
12-s-12,2Brpreparation and characterization
of new 12-s-12,2Br- surfactants
with an odd number of
-13.5
-8
methylenes in the spacer was
required. In this work the
-9
didodecyl dicationic dibromide
dimeric surfactants 12-s-12,2Br ,
-14.0
-10
with s=7, 9, and 11 were prepared
CH3-(CH2)11N(CH3)2(CmHm+2),Br
and characterized and their
-11
0
2
4
6
8
properties compared to those of
m (number of C atoms in the head group)
12-s-12,2Br- surfactants with s=2,
-14.5
0
2
4
6
8
10
12
3, 4, 5, 6, 8, 10, and 12.
s (number of C atoms in the spacer)
Figure caption: Dependence of ln cmc on the number of methylene units in the spacer for 12-s-12,2Brdimeric surfactants at 303 K. Inset: Dependence of ln cmc on the number of methylenes in the head group for
monomeric CH3(CH2)11N+(CH3)2(CmH2m+2),Br- at 298 K. The cmc´s are expressed as mole fractions.
Acknowledgments. This work was financed by the DGCYT (grant CTQ2009-07478), the European Union and
[1] Menger, F. M.; Keiper, J. N. Angew. Chem. Int. Ed. 2002, 39, 1906.
[2] Zana, R. J. Colloid Interface Sci. 2002, 248, 203.
[3] Rodríguez, A.; Graciani, M. M.; Martín, V. I.; Robna, I.; Moyá, M. L. J. Phys. Chem. B 2010, 114,
7817.
180
P36
A comparative thermodynamic analysis of clouding phenomenon in mixtures of
sugar-based surfactants with Triton X-100
J. A. Molina-Bolívar, M. Naous, J. M. Hierrezuelo, C. Carnero-Ruiz*
Department of Applied Physics II, University of Málaga, 29071-Málaga, Spain
*[email protected]
In the present communication we report a comparative study on the thermodynamic
of clouding phenomenon in mixed micelles of MEGA-10/Triton X-100 and OTG/Triton X100. The cloud point variation of mixed micelles with the Triton X-100 content has been
determined and the energetic parameters of the process have been estimated. The study was
performed in water and in the presence of NaCl. The cloud point of a nonionic surfactant can
be considered as the limit of its solubility as the phase separates at temperatures above the
cloud point [1,2]. The clouding species release their solvated water and separate out from the
solution. The presence of sugar surfactant monomers in the mixed micelle enhances the cloud
point of the system, being more pronounced in the case of OTG surfactant. Addition of
increasing amount of NaCl to micellar solution causes a continuous decrease in the cloud
point due to a marked alteration of the hydration layer of micelles provoked by the presence of
0
electrolyte. For all solutions the values of 'GCP
were positive and similar for both sugar-based
0
0
and 'SCP
are higher for OTG/Triton X-100 mixed micelles
surfactants. The values of 'H CP
than for MEGA-10/Triton X-100 system. The cloud point process is exothermic in nature for
0
the mixed micellar system, as proven by the negative value of 'H CP
. The exothermicity of
the clouding process is due to the aggregation of weakly hydrated micelles and their phasing
out into the condensed phase. The process is more exothermic as the presence of the sugarbased surfactant in the mixed micelle increases (with and without NaCl in the solution).
0
Furthermore, the negative values of 'SCP
indicate that the association of micelles in the
clouding phenomenon is entropically unfavorable, that is, the process is accompained with an
increase in the order of the micellar system. For a given proportion of Triton X-100 in the
mixture, for both sugar-based surfactants, the NaCl increases the randomness of the system
0
and hence T 'SCP
value becomes less negative. It was observed from the enthalpy-temperature
plots that the change in heat capacity of clouding phenomenon is negative, indicating the
important role played by dehydration in this thermodynamic process. The enthalpy-entropy
compensation plots are examined and found to exhibit an excellent linearly for this process.
This means that the change of enthalpy is almost compensated by a corresponding change in
entropy resulting in a smaller net free energy change. The micelle-water interactions were
characterized from the compensation temperatures, TC, which were evaluated from the slope
of the compensation lines. The values of TC decreases with NaCl concentration, which is
attributed to the fact that the presence of the electrolyte in the medium significantly alters the
micellar hydration layer.
Acknowledgements: This work has been financially supported by the “Consejería de Innovación,
Ciencia y Empresa de la Junta de Andalucía” (Project P07-FQM-02762).
[1] Molina-Bolívar, J. A.; Hierrezuelo, J. M.; Carnero Ruiz, C., J. Chem. Thermodynamics 2013, 57, 59.
[2] Molina-Bolívar, J. A.; Carnero Ruiz, C., Fluid Phase Equilibria 2012, 203, 58.
181
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Morphological and protein binding studies in lysine-based self-assembled
nano/micro-tubes
Isabel S. Oliveira, Maria J. Araújo and Eduardo F. Marques*
University of Porto (Portugal)
*[email protected]
Besides their self-assembly into micelles, vesicles and liquid-crystalline phases of different
nature, amino acid-based amphiphiles have the possibility of forming supramolecular aggregates, such as
tubules, fibers and ribbons, due to the common presence of a chiral centre (the amino acid chiral carbon)
and hydrogen bonding at the headgroups. These self-assembled nano/micro-tubules have high potential
as nanocarriers, due to their unique morphology that is able of efficiently loading biomolecules such as
DNA, drugs and proteins. [1]
In this work, we have synthesized a family of double-chained anionic surfactants derived from
the amino acid L-lysine, with variable degree of chain length mismatch. Previous works have shown that
this type of lysine-based surfactants have relatively low levels of ecotoxicity and hemolysis, and may
form tubules and stable vesicles in catanionic mixtures. [2,3] The compounds are designated simply by
m(Lys)n, with both the total chain length (m+n) and the length of the two chains in the same molecule
having been made different (mn). The thermodynamic parameters of the phase transitions in solution
have been determined by micro-DSC. The interaction of the derivatives of lysine with different proteins,
under different experimental conditions, was further investigated by polarized light microscopy,
fluorescence microscopy, AFM and cryo-SEM, with the aim of characterizing in detail the fine structure
of the m(Lys)n/protein aggregates formed.
Figure caption: 8Lys16 0.5% w/w aqueous dispersions: a) light micrograph showing tubular aggregates with
helicoidal structure (bar: 20 μm); b) cryo-SEM micrographs (bar: 1 μm); c) mechanisms for tubule formation; d) DSC
thermograms showing endothermic isotropization peaks.
Acknowledgements: We kindly acknowledge the Portuguese Science Foundation (FCT) and FEDER-Compete for
financial support through projects PTDC/QUI-QUI/115212/2009 and Pest/C-QUI/UI0081/2011.
[1] Zarif, L., J. Control. Release 2002, 81, 7-23.
[2] Brito, R. O.; Marques, E. F.; Silva, S. G.; Vale, M. L.; Gomes, P.; Araújo, M. J.; Rodriguez-Borges, J. E.; Infante,
M. R.; Garcia, M. T.; Ribosa, I.; Vinardell, M. P.; Mitjans, M., Colloids Surf. B: Biointerfaces 2009, 72, 80-87.
[3] Marques, E. F.; Brito, R. O.; Silva, S. G.; Vale, M. L.; Gomes, P.; Araújo, M. J.; Söderman, O., Langmuir 2008,
24, 11009-11017.
182
P38
Shake induced gelation of Particle-Polymer dispersions
R. Perea1, M. M. Ramos-Tejada1,* and P. Luckam2
1
University of Jaén, Department of Physics, 23071 Jaén, Spain.
2
Imperial College of Science, Technology and Medicine. Dept Chem. Eng. and Chem. Tech., SW72BY,
London,United Kingdom
*
[email protected]
Some dispersions of clay and silica particles in water in the presence of high molecular
weight polyethyleneoxide (PEO) that at rest are fluid, after a quick shake become solid [1-4], so
much so that, in some cases, they can be played with in the hands, see Figure 1.On leaving the
dispersions for a certain period of time, minutes to days depending on the polymer molecular
weight and concentration, the dispersions become liquid-like again. These dispersions have been
called “shake gels”.We have observed that it is possible a strong gel formation under a moderate
shake of the sample studied but not under a moderate shear rate. Besides, we have found that the
gel can be easily formed when we squirt the sample through a hypodermic needle. This seems to
indicate that the extensional shear could play an important role in the gel formation. A number of
physical variables are also determinant for producing the gel and controlling its behaviour. In this
work, we have studied the effect of the shape and size of the particles on the shake gel
formation.To that aim, we have mapped the “phase” behavior of silica (Ludox TM50), bentonite
and laponite dispersions in presence of PEO. At low t (ratio between the total mass of PEO and
the total area of clay surface) no shake gel was formed, but as t was increased, close the surface
saturation, the shake gel effect is observed, and at still higher t, shake gels no longer form. The
upper limit of PEO concentration for shake gel formation seems to depend of the particle shape.
Whereas in the case of the disc-shaped particles (laponite and bentonite) the upper limit is around
the saturation concentration, in the case of spherical particles (Ludox) this limit is around 2/3 of the
particle surface saturation. On the other hand, we have observed important differences between
bentonite (platelets of approximately 1000 nm x 1 nm dimensions) and laponite (platelets of
approximately 30 nm x 1 nm dimensions) dispersions. When we shaked the former, we found in
most cases an important and irreversible phase separation; on the contrary, in the case of the
laponite dispersion the phase separation is not extensive and it is easily reversible.These results can
contribute to the understanding of the shake gel formation.
Figure caption: Aqueous LudoxTM-50-PEO mixture contains 25% of silica and 0.4% PEO Mw~4000000. (A)
before shake it;(B) after completion of shaking.
Acknowledgements: Financial support by Junta de Andalucía, Spain (Project PE2008-FQM3993) and Spanish
Ministry of Science and Innovation (FIS2010-19493) is greatly acknowledged.
[1] Cabane, B.; Wong, K.; Lindner, P.; Lafuma, F., J. Rheol.1997, 41(3), 531-547.
[2] Liu, S. F.; Lafuma, F.; Audebert, R., Colloid Polym. Sci. 1997, 272(2), 196-203.
[3] Pozzo, D. C.; Walker, L. M., Colloids and Surfaces A: Physicochem. Eng. Aspects 2004, 240, 187-198.
[4] Zebrowski, J.; Prasad, V.; Zhang, W.; Walker, L. M.;Weitz, D. A., Colloids and Surfaces A: Physicochem.
Eng. Aspects 2003, 213, 189-197.
183
P39
Permeability-Tunable Microgels
Benjamín Sierra-Martín1, Ana Maldonado-Valdivia1,*, Antonio Fernández-Barbero1
1
*[email protected]
We study the electrophoresis of a thermo-sensitive and ionic microgel and
demonstrate its free-draining character when the polymer network is ionized, in contrast to the
more conventional charged hard spheres or neutral microgels. The results are rationalized by
considering the Ohshima theory for polyelectrolyte-coated particles; the electrophoretic
mobility P is determined by the balance between the particle charge and the friction
coefficient, which in turns depends on the particle swelling and viscosity. Interestingly, we
find that the viscosity K affecting the particle permeability is associated to the local
environment of the network; it shows power law dependence with the salt concentration,
Kac0.2 and account for the different Pac scaling. These experiments can be used as a strategy
to explore the viscosity of water molecules inside the microgel, being complementary to other
direct methods such as nuclear magnetic resonance.
184
P40
Rational design of cleavable cationic gemini surfactants: exploring the
multifunctionality of serine as headgroup
Sandra G. Silva1, Cláudia Alves1, Ana M. S. Cardoso2, Amália S. Jurado2,3,
Maria C. Pedroso Lima2,3, M. Luísa C. do Vale1,*, Eduardo F. Marques1,*
1
Centro de Investigação em Química (UP), Department of Chemistry and Biochemistry, Faculty of
Science, University of Porto, Rua do Campo Alegre s/n, P-4169-007, Porto, Portugal.
2
CNC - Centre for Neuroscience and Cell Biology, University of Coimbra, Portugal.
3
Department of Life Sciences, University of Coimbra, Portugal.
*[email protected]; *[email protected]
Gemini surfactants have emerged as a new class of self-asssembling molecules in the 1970s and
since then have attracted considerable interest both in fundamental and in applied contexts. Cationic
gemini surfactants are of particular interest owing to their potential for biomedical applications. The
conventional bis-quats have proved to be highly promising in delivering genetic material to cells and as
synthetic additives in liposome formulations for drug delivery.[1] However, they often exhibit relatively
high levels of cytotoxicity and skin irritancy, both detrimental to their use in biomedical applications.
Therefore, considerable efforts have been made to design and synthesize novel gemini surfactants,
possessing enhanced toxicological profiles, by using biomolecules (sugars, amino acids and peptides) as
polar headgroup.
In this context, our research team has been engaged in the synthesis and physicochemical
evaluation of amino acid based monomeric and dimeric surfactants. [2, 3] In the present work, the results
obtained with the amine series and two novel series of cationic gemini surfactants based on serine are
presented. The novel surfactants have a cleavable amide or ester bond between the polar head group and
the spacer. [4] The effects of molecular structure, nature of spacer linkage and spacer length on the
interfacial and cytotoxic properties of these gemini surfactants are presented. The compounds show
enhanced interfacial properties and lower cytotoxicity, in comparison with conventional bis-quat gemini
and monomeric surfactants, which demonstrates the possibility of their use in technical and biological
applications.
Figure caption: Molecular structures of serine-based gemini surfactants
Acknowledgements: Thanks are due to Portuguese Science Foundation (FCT) and FEDER-Compete for financial
support through PTDC/QUI-BIQ/103001/2008, PTDC/QUI-QUI/115212/2009, REDE/1517/RMN/2005, Pest/CQUI/UI0081/2011. SGS and AMSC acknowledge FCT for PhD grants SFRH/BD/61193/2009 and
SFRH/BD/63288/2009, respectively.
[1] Cardoso, A. M. S.; Faneca, H.; Almeida, J. A. S.; Pais, A.; Marques, E. F.; de Lima, M. C. P.; Jurado, A. S.,
Biochim. Biophys. Acta 2011, 1808, 341.
[2] Silva, S. G., Rodríguez-Borges, J. E., Marques, E. F., do Vale, M. L. C., Tetrahedron 2009, 65, 4156-4164.
[3] Silva, S. G., Fernandes, R. F., Marques, E. F., do Vale, M. L. C., Eur. J. Org. Chem. 2012, 345-352.
[4] Silva, S. G.; Alves, C.; Cardoso, A. M. S.; Jurado, A. S.; Pedrodo de Lima, M. C.; Vale, M. L. C. Marques, E. F.,
Eur. J. Org. Chem. 2013, 1758-1769.
185
P41
Kinetics And Mechanisms of Thermal Degradation of Water Borne
Poly(BA/MMA)/Graphene Composites
D. Spasevska1, Alejandro Arzac3, J. Blazevska-Gilev 1, R. Fajgar2 and R. Tomovska3,4,*
1
Faculty of Technology and Metallurgy,”Ss.Cyril&Methodius” University,
1001 Skopje, R.of Macedonia.
2
Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Department of Aerosols and Laser
Studies, Rozvojová 135, 165 02 Prague 6, Czech Republic
3
POLYMAT and Departamento de Química Aplicada, Facultad de Ciencias Químicas, University of the
Basque Country UPV/EHU, Joxe Mari Korta zentroa, Tolosa etorbidea 72, Donostia-San Sebastián
20018, Spain
4
IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain.
*
[email protected]
The aim of this research is to study thermal stability of the water borne poly(methyl
methacrylate/butyl acrylate) p(BA/MMA)/graphene nanoplateltes (GNPs) composites,
prepared by emulsion mixing technique [1,2]. The polymer latex with 40 % solid content,
composed from p(MMA/BA), in ratio 50/50 wt%, was synthesized by a seeded
semicontinuous emulsion polymerization. The GNPs were dispersed in water by means of
sonication in presence of polyvinyl pyrrolidone (PVP) and afterward mixed with the polymer
latex in order to obtain hybrid aqueous dispersions with GNPs content of 0.5 wt%, 1 wt%; 2
wt%; and 3 wt% in relation to polymer. The composite films were prepared by water
evaporation under standard ambient conditions and characterized by means of Raman
spectroscopy, Fluorescence Quenching Microscopy (FQM) and SEM imaging, while thermal
properties of the composites were studied by Thermo Gravimetric Analysis (TGA).
The TGA analyses have been performed by heating at two different rates up to
around 723 K. The results have been used for making kinetic study of the thermally activated
process of P(BA/MMA)/graphene composites degradation. As the easily measured weight
changes of the samples in the defined thermal conditions are a suitable sensor for their
structural and chemical changes, by means of a method of like Gropjanov’s one, the useful
information for identifying the kinetic parameters of the investigated process taking place in
the course of thermal treatment have been obtained [3].
The thermal variation of the rate constant as well as the kinetic equations for the
examined process depending on the GNPs content in the composites has been derived. The
activation energies of the composites are determined and their dependence on the GNPs
content is discussed. As well, the controllable mechanism of the examined process has been
determined [4].
[1] Yousefi, N.; Gudarzi, M. M.; Zheng, Q.; Aboutalebi, S. H.; Sharif, F.; Kim, J. -K.; J.Mater.Chem.
2012, 22 12709.
[2] Syurik, Y.V.; Ghislandi, M.G.; Tkalya, E.E.; Paterson, G.; McGrouther, D.; Ageev, O.A.; Loos, J.;
Macromol. Chem. Phys. 2012, 213, 12511258.
[3] Gropjanov, V. M.; Abbakumov, V. G.; Him.i him.tehnol. 1975, 18, 2, 202.
[4] Hillier, J.; Bezzant, T.; Fletcher, T. H.; Energy Fuels, 2010, 24, 2841-2847.
186
P42
Poly(N-vinylcaprolactam) nanogels: A light scattering study
José Callejas-Fernández1,*, Josetxo Ramos2, Ainara Imaz2, Jacqueline Forcada2, Manuel
Quesada-Pérez3, Arturo Moncho-Jordá1
2
1
Departamento de Física Aplicada, Facultad de Ciencias, 18071 Granada (Spain).
POLYMAT, Bionanoparticles Group, Departmento de Química Aplicada, UFI 11/56, Faculty of
Chemistry, University of the Basque Country UPV/EHU, Apdo. 1072, 20080 Donostia (Spain).
3
Departamento de Física, Escuela Politécnica Superior, 23700 Linares, (Spain).
*
[email protected]
Nowadays, nano/microgels formed by biocompatible polymers emerge as promising
particles in the field of biomaterials-biomedicine. Polyvinylcaprolactam nanogels (PVCL)
belong to this class of nanoparticles. They can vary their size in response to external stimuli as
temperature, pH, solvent properties, external fields, among others. In this work, a light
scattering (LS) study on charged and uncharged PVCL anionic nanogels in water is presented.
The goal of the research is to discuss on the validity of LS methods to explore both
“individual” properties of nanogels (size, shape, internal structure) and “bulk” properties as
the structure of its colloidal dispersions.
400
PEGDA 2
350
15 ºC
30 ºC
40 ºC
50 ºC
300
I(q) a.u
250
200
150
100
50
0
0.002 0.004 0.006 0.008 0.010 0.012 0.014 0.016 0.018 0.020 0.022
-1
q (nm )
Figure caption: Experimental form factor corresponding to a PVCL nanogel at different temperatures.
Acknowledgements: This work is supported by Spanish Plan Nacional de Materiales, Projects:
MAT2012-36270-C01, -C02 and –C04 and MAT2009-13155-C04-02.
[1] Ramos, J.; Imaz, A.; Forcada, J., Polym. Chem. 2012, 3, 852-856.
[2] Ramos, J; Imaz, A.; Callejas-Fernández, J.; Barros-Barbosa, L.; Estelrich, J.; Quesada-Pérez, M.;
Forcada, J., Soft Matter 2011, 7, 5067-5082.
187
P43
New sorbents based on silica-carrageenan hybrids
Rui S. Carvalho*, Daniela S. Tavares, Ana L. Daniel-da-Silva and Tito Trindade
CICECO-Chemistry Department, Aveiro Institute of Nanotechnology, University of Aveiro,
3800-193 Aveiro, Portugal
*
[email protected]
The discharge of dyes and toxic metal ions in water supplies is a matter of concern
due their harmful impact on the environment. In the last years a number of nanoengineered
materials have emerged as new sorbents for water decontamination. Examples include the use
of magnetic silica nanoparticles functionalized with dithiocarbamate groups for the removal of
Hg2+ [1] and nanoparticles coated with biopolymers obtained from renewable resources to
remove dyes [2]. This research has focus on the development of silica-biopolymer hybrids that
merge the above described functionalities, aiming their application as sorbents in water
purification processes.
Hybrid materials comprising amorphous SiO2 and dithiocarbamate derivatives and
the polysaccharide -carrageenan were synthesized, in the form of bulk materials and
nanocomposite particles. Siliceous-polysaccharide hybrids (bulk form) were synthesized by
hydrolytic co-condensation of tetraethyl orthosilicate (TEOS) and a siloxydithiocarbamate
(SiDTC) precursor in aqueous solutions of -carrageenan (2 wt%). The resulting solution
formed gels, at room temperature, due to the gelling properties of -carrageenan. Differential
scanning calorimetry (DSC) analysis showed that hybrid materials undergo an endothermic
transition upon heating, due to gel-to-sol transition. The ATR-FTIR spectra of dried gels was
in agreement with the presence of a siliceous network in the carrageenan gel, and indicates the
presence of the dithiocarbamate groups in those gels prepared using SiDTC.
In a second step these hybrid materials were confined to nanometric dimensions
using water-in-oil microemulsions. Carrageenan hydrogel nanoparticles were first prepared in
microemulsions comprising n-heptane as the organic solvent, cetyltrimethylammonium
bromide (CTAB) as surfactant and 1-butanol as the co-surfactant and in the presence of
magnetite nanoparticles [3]. The magnetic hydrogel nanoparticles were then encapsulated in
amorphous siliceous shells, by performing the hydrolytic co-condensation of TEOS and
SiDTC within microemulsion droplets. The spherical morphology of the resulting composite
nanoparticles was confirmed by electron microscopy, with particles showing an average
diameter of 60 nm. The use of these hybrid materials for the magnetic removal of
contaminants from water will be discussed, namely by considering the chemical
functionalities associated to their composition. For example, the presence of dithiocarbamate
groups as suitable chelating moieties for metal ions removal and the presence of sulfonate
groups from carrageenan to attach electrostatically cationic dyes.
Acknowledgements: FCT - Fundação para a Ciência e Tecnologia (PTDC/CTM-NAN/120668/2010,
Pest-C/CTM/LA0011/201) FSE and POPH for funding. We thank the RNME (National Electronic
Microscopy Network) for TEM facility.
[1] Girginova, P. I.; Daniel-da-Silva, A. L.; Lopes, C. B.; Figueira, P; Otero, M.; Amaral, V. S.; Pereira,
E.; Trindade, T. J. Colloid Interface Sci., 2010, 345, 234-240.
[2] Crini G., Progr. Polym. Sci., 2005, 30, 38-70.
[3] Daniel-da-Silva, A. L.; Fateixa, S.; Guiomar, A. J.; Costa, B. F. O.; Silva, N. J. O.; Trindade, T.;
Goodfellow, B. J.; Gil, A. M., Nanotechnology 2009, 20, 355602.
188
P44
Lysine based cationic surfactants at the air-water interface. Mixed monolayers
with DPPC: An investigation into the antimicrobial activity
Aurora Colomera, Lourdes Pereza, Maria Rosa Infantea, Ramon Ponsa, Angels Manresab,
Maria Jose Espunyb, Aurora Pinazoa,*
a
Department de Tecnologia Química i de Tensioactius, Institut de Química Avançada de Catalunya,
CSIC. Jordi Girona 18, 08034 Barcelona, Spain
b
Laboratori de Microbiologia, Facultat de Farmàcia, Universitat de Barcelona. Av. Joan XIII s/n,
08028 Barcelona, Spain
*
[email protected]
Antimicrobial resistance to antibiotics is a major global public health threat, thus
development of new antimicrobial compounds is of great significance in biomedicine
chemistry. Cationic surfactants exhibit antimicrobial activity and have been used as
disinfectants in hospitals and in food and pharmaceutical industry. These types of applications
require compounds that do not present hemolytic or cytotoxic activities. To search for new
antimicrobial agents, our group has synthesized cationic surfactants from different amino
acids. Amino acid based surfactants can be prepared from renewable raw materials and are
characterized by their high biodegradability and moderate toxic levels.
We report studies that contribute to elucidate the relationship between surface activity
of three lysine based surfactants and their antimicrobial activity. To this end, the adsorption
properties at the air/liquid interface of spread monolayers were studied. Under saline
conditions their spread monolayers can be compressed. Mixed monolayers with DPPC showed
an expansion of the DPPC monolayer which suggests interactions of the compounds with
DPPC molecules that strongly depend on the surfactant structure. The antibacterial activity
against Staphylococcus aureus and Escherichia coli bacteria has been performed by electron
microscopy observation. The three surfactants caused multiple forms of damage as evidenced
by structural alterations, leakage of internal material and cell destruction on the bacteria.
189
P45
Supramolecular aggregation in cationic/anionic mixtures of
calixarene and serine-based surfactants
Catarina Costa1, Vitor Francisco2, M. Luísa C. do Vale1, Luis Garcia-Rio2,*,
Eduardo F. Marques1,*
1
University of Porto, Rua do Campo Alegre, s/n, P-4169-007 Porto, Portugal.
2
Centro Singular de Investigación en Química Biológica y Materiales Moleculares (CIQUS),
Dept. of Physical Chemistry, University of Santiago de Compostela, Santiago de Compostela, Spain.
*[email protected]; *[email protected]
Nano-structured assemblies of variable complexity—such as tubules, fibers, micelles, vesicles,
and disks—can be created through molecular self-organization of small organic compounds and
conventional amphiphiles, making use of noncovalent interactions [1]. The macrocycle psulfonatocalix[4]arene (SC4), is a known receptor for organic ammonium cations in aqueous solution,
showing strong binding ability for these guests due to their S-rich cavity and additional anchoring points
offered by the sulfonate groups. In a previous work, we have studied the interactions in aqueous solution
between SC4 and tetradecytrimethylammonium bromide (a micelle-forming surfactant), showing the
formation of giant unilamellar vesicles after sonication of mixed SC4-TTAB dispersions [2]. These
vesicles could be stored without use of cryo-protectants by lyophilization, and then rehydrated without
change size or shape. In this work, we have explored the self-assembling properties of mixtures of SC4
with cationic serine-based surfactants, with C16 and C12 alkyl chains (termed 16Ser and 12Ser,
respectively). For the Ser16/SC4 system, in dilute aqueous solution (less than 20 mM), we have found
that there is a range of mixing ratios where flexible supramolecular tubules, with a few μm long, are
formed (Figure A-C). The formation process is slow (some days) and the aggregates appear in fast
Brownian motion, apparently breaking into and reforming from spherical aggregates (presumably
liposomes). Both Ser16/SC4 and Ser12/SC4 mixed systems have been studied by surface tension, light
microscopy, cryo-SEM and NMR, and the conspicuous aspects of supramolecular aggregation therein
found will be presented and tentatively rationalized.
Figure caption: Supramolecular Ser16/SC4 tubules: light microscopy (A and B) and cryo-SEM (C). E) Possible
interaction between the two molecules and respective bilayer formation. Bar: A, B - 20 μm; C - 6 μm.
Acknowledgments: Thanks are due to the Portuguese Science Foundation (FCT) and FEDER-Compete for financial
support through projects PTDC/QUI-QUI/115212/2009 and Pest/C-QUI/UI0081/2011. V. F. acknowledges FCT for
the PhD Grant SFRH/BD/43836/2008.
[1] Shimizu, T.; Masuda, M.; Minamikawa, H.; Chem. Rev. 2005, 105, 1401-1444.
[2] Francisco, V.; Basilio, N.; Garcia-Rio, L.; Leis, J.R.; Marques E.F.; Vázquez-Vázquez, C.; Chem. Comm., 2010,
46, 6551–6553.
190
P46
The role of the ionic specificity on the nanogel aggregation
Verónica D.G. González1, Delfina Bastos González2, José Callejas Fernández2,
María Tirado Miranda2,*
1
INTEC (Universidad Nacional del Litoral – CONICET), Santa Fe, Argentina
Universidad de Granada, Dpto. Física Aplicada, Campus Fuentenueva s/n, 18071 Granada Spain
*
[email protected]
2
Nanogels are cross-linked polymeric chains dispersed in water that are able to swell
or deflate in response to changes in external triggers such as pH, temperature and
biomolecules. This behaviour makes them useful for applications in fields such as drug
delivery, regenerative medicine, nanopatterning and chemical biosensing [1].
In this work, we focused on thermosensitive nanogels composed of poly(N-isopropyl
acrilamide). This system has a lower critical solution temperature, around 32 ºC in aqueous
solutions. Thus, the nanogel swells at low temperatures and collapses at high ones [2]. We
studied the aggregation kinetics and morphological properties of nanogels as function of
temperature, ionic specificity and electrolyte concentration. Depending on the nature of the
ion employed, we found a variety of behaviour ranging from no aggregation to DLCA regime.
However, the ionic specificity revealed an equilibrium distribution of clusters-nanogels for
determined experimental conditions. This equilibrium distribution was able to keep up to 100
minutes and then, the aggregation process continued spontaneously.
Acknowledgement: Financial support from the Ministerio de Economía y Competitividad of Spain
(project No. MAT2012-36270-C04-02).
[1] Saunders, B.R., Laajam, N., Daly, E., Teow, S., Hu, X., Stepto, R., Adv. Colloid Interface Sci. 2009,
147, 251-262.
[2] López-León, T., López-López, J. M., Odriozola, G., Bastos-González, D., Ortega-Vinuesa, J. L., Soft
Matter 2009, 6, 1114-1116.
191
P47
Rhamnolipid characterization and its influence on dppc bilayer organization(
poster, bioinspired systems)
E. Haba1, R. Pons2, L. Pérez2, A. Manresa1, A. Pinazo2,*
1
Laboratori de Microbiologia, Facultat de Farmàcia, Universitat de Barcelona. Av. Joan XIII s/n, 08028
Barcelona, Spain
2
Department de Tecnologia Química i de Tensioactius, Institut de Química Avançada de Catalunya,
CSIC. Jordi Girona 18, 08034 Barcelona, Spain
*
[email protected]
The pressing need for more biosustainable, biocompatible and biodegradable
surfactant based products make the study of biosurfactants an important area of research.
Biosurfactants are surface active biomolecules that are produced by a variety of different
microorganism. Rhamnolipids produced by Pseudomona aeruginosa consist of one or two
rhamnose molecules linked to one or two molecules of hydroxydecanoic acid. Rhamnolipids
have the two main properties of surfactants, show strong surface activity and self assembly in
water. Understanding their fundamental physico chemical properties and how these relate to
their biological roles are keys to their wider exploitation. Despite the importance that the
interaction between rhamnolipids and membranes might play in their biological mechanism of
action very little is known, especially regarding rhamnolipid-phospolipid molecular
interactions. The aim of this work was to study the ability of RL8 mixture to form vesicles in
absence and presence of the phospholipid DPPC. We employed size and Z- potential to
characterise the size and the external charge of the vesicles and SAXS to measure the vesicle
bilayers characteristics. The biosurfactant forms ordered bilayers with long repeating
distances, these long repeating distances are stabilized by the charging of the bilayer and also
by a strong fluidity of the bilayers. The ability of RH to increase the fluidity of DPPC bilayers
may be related with the strong hemolytic power of these molecules
192
P48
Structure and plasmon coupling of 2D Au@PNiPAM microgel arrays with
thermally controlled interparticle gap
Ana Maldonado-Valdivia1,*, Joaquim Clara-Rahola1, Rafael Contreras-Cáceres1,
Benjamín Sierra-Martín1, Antonio Fernández-Barbero1
1
*
[email protected]
2D nanoparticle arrays are fabricated using core-shell Au@PNiPAM nanoparticles.
The PNiPAM shells act as tunable temperature-sensitive mechanical spacers, just to set the
interparticle gaps. Deviation from linearity due to the soft nature of the polymer shells is
found between gaps into the arrays and those expected from the (colloidal) particle sizes at
bulk. This lack of linearity transfers to the particle structures making the ensembles better
ordered at high temperature, contrary to the classical behavior for harder particles. Vertical
plasmon coupling between the particle cores and an Au substrate becomes apparent during the
deswelling-drying process, while any horizontal lateral coupling between the Au cores is
detected. The polymer around the Au cores is finally removed from the 2D ensembles,
keeping the arrays their mechanical stability.
193
P49
Influence of xenobiotics on the stability of natural micellar aggregates
J. Morales1,*, J. A. Manso1, M. Arias-Estevez2 and J. C. Mejuto1
2
1
Plant Biology and Soil Science Department, University of Vigo, 32004 Ourense, Spain.
*
[email protected]
Humic acids (HAs) are the principal component of humic substances, which are the
major organic constituents of soil [1]. They change the soil characteristics, favouring the ion
exchange [2] and the absorption of nutrients. Organic matter in soil also facilitates the
adsorption mechanisms of hazardous substances as pesticides [3]. It was determined by
dynamic light scattering that there is a correlation between some Physical-Chemistry
characteristics of these natural colloidal aggregates (from extracts of soil’s humic substances)
as the conductivity, the polidispersity, the mobility, the particle size and especially the Zeta
potential and its high impact on chemical reactivity with xenobiotics. The excess of electrical
charge at the interface is responsible for surface conductance and it is a good parameter to
evaluate the stability of these humic substances. Its colloidal behaviour can be significantly
influenced by the solution pH [4]. The appearance of pesticides in the medias analyzed causes
a decrease on the stability of natural aggregates colloidal, more pronounced at lower HAs
concentrations. Thus modifying some of its properties associated with its colloidal nature. The
inclusion of carbofuran shows greater destabilization on the system than the metalaxyl
inclusion.
Figure caption: (left). Influence of humic acids concentration on the Zeta potential at pH=9 in absence of
pesticide. Nitric acid was used as acid titrator and sodium hydroxide as alkaline. T= 25
(right). Variation of Z-potential in the humic colloidal aggregates. [Pesticide]=0.005 M; [HAs]=0.02 g·L-1: in
absence of pesticide (z), in the presence of carbofuran () and in the presence of metalaxyl (V).
Acknowledgements: The authors thank the Xunta de Galicia (10PXIB383187PR) for financial support.
Jorge Morales thanks the University of Vigo for a research-training grant (P.P. 0022 122I 641.03).
[1] Stevenson, F. J. Humus Chemistry: Genesis, Composition, Reactions. John Wiley & Sons: NY, 1994.
[2] Zhou, P.; Yan, H.; Gu, B., Chemosphere 2005, 58, 1327-1337.
[3] Briceño, G.; Palma, G.; Durán, N., Crit. Rev. Environ. Sci. Technol. 2007, 37, 233-271.
[4] Ghosh, S.; Mashayekhi, H.; Pan, B.; Bhowmik, P.; Xing, B., Langmuir 2008, 24, 12385-12391.
194
P50
Stability of carbofuran in restricted aqueous media
J. Morales1,*, J. A. Manso2, A. Cid3, M. A. Iglesias-Otero1 and J. C. Mejuto1
1
2
Cancer Research Center, 37007 Salamanca, Spain
3
Chemistry Department, REQUIMTE-CQFB, University Nova of Lisbon, 2829-516 Monte de Caparica,
Portugal.
*
[email protected]
Carbofurans (CFs) are chemically carbamic acid derivatives and they have been
employed successfully as insecticides because of the capability for controlling pests [1].
In agriculture, composition of the soil can be variable. Presence of restricted water
environments carries that soil compounds and structure influences hardly the action of these
carbamates, that furthermore posses an important toxicity [2].
In this work it is showed the influence of some oil/water microemulsions on the
stability of different CFs (3-Hydroxyc-arbofuran (HCF) and 3-Keto-carbofuran (KFC) shown
in Figure) in basic media. The behavior under the action of aqueous media is analyzed using a
pseudophase model [3].
For CF and HCF was found that presence of water in restricted media implies an rise
of its basic degradation. On the contrary, for KCF, an inhibition was observed. This main
difference can be explained due to the absence of electronic conjugation of the basic
hydrolysis products in microemulsions because to the presence of strong hydrogen-bond
interactions.
Figure caption: Chemical structures of carbofuran and two of its derivatives: 3-Hydroxycarbofuran (HCF) and 3-Keto-carbofuran (KFC)
Acknowledgements: Morales and Iglesias-Otero thanks thanks University of Vigo for a research grant.
Dr. Cid thanks to MCTES-FCT (Portugal) his post-doctoral grant (SRFH/BPD/78849/2011),
[1] Alvares, A. P.; in: B. Ballantyne, T.C. Marrs (Eds), Clinical and Experimental Toxicology of
Organophosphates and Carbamates: Pharmacology and Toxicology of Carbamates. ButteworthHeinemann, UK, 1993.
[2] Tripathi, G.; Kachwaga,N.; Dabi, I. Pestic. Biochem. Physiol. 2010, 96, 30-35.
[3] García Río, L.; Hervés, P.; Mejuto, J.C.; Pérez-Juste, J.; Rodriguez-Dafonte, P.; Langmuir, 2000, 16,
9716-9721.
195
P51
Effect of mixed crowding media on the diffusion of alpha-chymotrypsin
Isabel Pastor1,2, Eudald Vilaseca1, Sergio Madurga1, Josep Lluís Garcés3, Marta Cascante2
and Francesc Mas1,*
1
Departament of Physical Chemistry and Research Institute of Theoretical and Computational
Chemistry of the University of Barcelona (IQTCUB), Barcelona (Spain)
2
Department of Biochemistry and Molecular Biology and IDIBAPS, University of Barcelona (UB),
Barcelona (Spain,)
3
Departament of Chemistry and AGROTECNIO. Universitat de Lleida (Spain)
*
[email protected]
The interior of the living cell is highly concentrated and structured with molecules
having different shapes and sizes. While a single species of macromolecules of cellular
environments may not be concentrated, the total volume occupied by all macromolecules can
constitute up to 40% of its total mass [1]. The high concentration of macromolecules in
intracellular environments results into non-specific interactions (macromolecular crowding),
which have a great influence on the kinetics and thermodynamics of possible reactions that
occur in these systems, e.g. diffusion processes and reaction kinetics [2]. Quantitatively,
macromolecular crowding reduces the diffusion coefficient as compared to aqueous solutions,
and qualitatively, diffusional motion could be changed toward anomalous diffusion, this mean
time dependent diffusion [3-4]. Usually, studies of how macromolecular crowding affects
protein´s diffusion are carrying on in homogeneous in vitro media, thus mean that only one
size of crowder agent is present by experiment4. However, as it was explained before, the
cytoplasm is composed by a large number of different species of macromolecules, we think
that is important to carry on a study in heterogeneous crowding media composed by crowded
agents with different sizes. In this work we study the diffusion of a model protein (alphachymotrypsin) in in vitro mixed crowded solution using three type of Dextran molecules as
crowder agents [5].
Acknowledgements: The research leading to these results has received funding from the Spanish
Ministry of Education and Science (Projects CTM2009-14612 and CTM2012-39183), and from
Generalitat de Catalunya” (2009SGR00465 and XRQTC). IP thanks the Juan de la Cierva Programo f
the Spanish Ministry of Science.
[1] Ellis R., J. Trends Biochem. Sci., 26 (2001) 597-604; Hall D. and Minton A.P., Biochim. Biophys.
Acta, 2003, 1649, 127; Minton A.P., J. Biol. Chem., 2001, 276, 10577.
[2] Zimmerman S. B. and Minton A. P., Annu. Rev. Biophys Biomol. Struct., 1993, 22, 27; Echevería, C.
et al., J. Phys. Codens. Matter, 2007, 19, 065146; Zhou, H.X. et al., Annu. Rev. Biophys., 2008, 37,
375.
[3] Weiss M. et al. Biophys J. 2004, 87, 3518; Saxton M.J., Biophys. J., 2008, 94, 760.; Isvoran, A. et al.,
Rev. Rom. Chem., 2008, 53, 415; Vilaseca, E. et al., PCCP, 2011, 13, 7396.
[4] Banks D.S. and Frandin C. Biophys. J. 2005, 89, 2960; Pastor, I. et al., J Phys. Chem B, 2010, 114,
4028; Erratum, ibib, 2010, 114, 12182.
[5] Pastor, I. et al., PCCP, 2013 (in press).
196
P52
Stability of the polymer layers formed by the layer-by-layer method
R. Perea1, M. M. Ramos-Tejada1*, K. Rudzka2 and A. V. Delgado2
2
1
University of Jaén, Department of Physics, 23071 Jaén, Spain.
University of Granada, Faculty of Science, Department of Applied Physics, 18071 Granada, Spain
*
[email protected]
There are numerous studies about the preparation of composite particles consisting of cores
covered with shells of different chemical composition. Since the properties of such particles
(magnetic, optical, electric, adsorptive, etc.) can be altered by appropriate coatings, they may
be useful in many applications. The layer-by-layer, LbL, method is an interesting and versatile
method to construct coated particles. The technique consists in a nanoscale coating of colloid
particles with multiple layers of various kinds, utilizing electrostatic interactions for the
buildup of the layers [1-4]. Usually, in the LbL colloid coating method, a polyelectrolyte
solution of concentration sufficient to cause adsorption saturation is added to a colloidal
suspension. The key point is that the first added polymer bears an opposite charge to that on
the core, thereby utilizing electrostatics for adsorption. Hence, when the polymer layer is
adsorbed the charge on the surface of the particles is reversed, which aids in the deposition of
subsequent layers of a wide range of oppositely charged components. In this work, magnetite
cores have been coated with several polymer layers (polyethyleneimine,
poly(styrenesulfonate) and poly(diallyldimethylammonium chloride)) using the LbL
technique. The stability of the layers with time has been monitorized by zeta potential
measurements. We have found that when magnetite is covered with a polymer monolayer the
stability of the layer is low, and within a few days an important desorption of the polymer was
observed. The multilayer formation improves the stability of the coating although polymer
desorption is observed on samples after 20 days.
Acknowledgements: Financial support by Junta de Andalucía, Spain (Project PE2008-FQM3993) and
Spanish Ministry of Science and Innovation (FIS2010-19493) is greatly acknowledged.
[1] Caruso, F., Top Curr. Chem., 2003, 227, 145-168.
[2] Chen, T.; Somasundaran, P., J. Am. Ceram. Soc., 1998, 81, 140-144.
[3] Dokoutchaev, A.; James, J. T.; Koene, S. C.; Pathak, S.; Prakash, G.; Thompson, M. E., Chem.
Mater.,1999, 11, 2389-2399.
[4] Keller, S. W.; Johnson, S. A.; Brigham, E. S.; Yonemoto, E. H.; Mallouk, T. E., J. Am. Chem. Soc.,
1995, 117, 12879-12880.
197
P53
Ostwald ripening inhibition of concentrated limonene emulsions
L. M. Pérez-Mosqueda1, P. Ramírez1,* and J. Muñoz1
1
Departamento de Ingeniería Química, Facultad de Química. Universidad de Sevilla, P. García
González 1, 41012 Sevilla, Spain.
*
[email protected]
Limonene emulsions stabilized by Pluronic P9400 are destabilized by both, Ostwald
ripening and creaming. The former is more pronounced in concentrated emulsions (I =50%)
and both destabilization processes increase with surfactant concentration in the range 3%-5%
(w/w) where monomodal submicron emulsions are obtained (d3,2 ~ 0.8 Pm, Uniformity ~
0.35).
In the present work, we focus on the development of a formulation that inhibits
Ostwald ripening for concentrated limonene emulsions (I = 50%) containing 3% (w/w)
Pluronic P9400 as emulsifier. As it is well-known this destabilization process can be delayed
and eventually stopped by adding a water insoluble compound to the oil phase [1,2].
Three different additives (tetradecane, silicone oil and rosin gum) have been added to
limonene in order to study their properties as Ostwald ripening inhibitors. The droplet size
growth in the presence of each of these chemicals was monitored by means of laser diffraction
(Mastersizer X, Malvern).
The influence of additive concentration was also studied. It is shown that a low
concentration of tetradecane and silicone oil (ca. 2% (w/w)) drastically reduced the Ostwald
ripening rate. Nevertheless, a much higher concentration of rosin gum was needed to prevent
droplet growth (>15%(w/w)).
Although emulsions containing tetradecane and silicone oil maintained the same
droplet size, they became destabilized by creaming. However, the addition of rosin gum at
concentrations higher than 15% (w/w) resulted in stable limonene emulsions avoiding
creaming separation. This may be due to the combination of two cooperative effects. Rosin
gum increases the density of the disperse phase, hence the creaming driving force is
diminished and on top of that the droplet size turns out to be lower (d3,2 ~ 0.5 Pm, Uniformity~
0.35 ), which will also prevent creaming from occurring.
Acknowledgements: The financial support received (Project CTQ2011-27371) from the Spanish
Ministerio de Economía y Competitividad (MINECO) and from the European Commission (FEDER
Programme) is kindly acknowledged. L. M. Pérez-Mosqueda also acknowledges the Universidad de
Sevilla for its financial support (Beca PIF IV Plan Propio de Investigación).
[1] Schmitt, V.; Cattelet, C.; Leal-Calderon, F. Langmuir, 2004, 20, 46-52
[2] Taisne, L.; Cabane, B. Langmuir, 1998, 14, 4744-4752
198
P54
Studies on the colloidal stability of F-DPPC and DPPC liposomes. The influence
of Ca2+ and the interdigited bilayer on the aggregation process
Gerardo Prieto1,*, Paula Toimil1, Rocío Daviña1 and Félix Sarmiento1
1
Biophysics and Interfaces Group, Department of Applied Physics, Faculty of Physics, University of
Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
*[email protected]
Fluorinated phospholipids present a remarkable biological interest due to the high
sensitivity of fluorine-19, which enables them to be identified in membranes. The use of liposomes
composed by fluorinated phospholipids as vehicles for drug delivery has been subject of an
increasing number of research in recent years. Previous works have demonstrated that liposomes
partially or totally formed by phospholipids containing fluorinated tails modify the thermotropic
phase behavior of the bilayer, diminish the membrane permeability and increase the coloidal
stability of the such systems [1,2]. In this work, the aggregation of unilamellar liposomes
composed by 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1-palmitoyl-2-[16fluoropalmitoyl]-sn-glycero-3-phosphocholine (F-DPPC), in presence of calcium ions at
temperatures below and above the phase transition of both phosphlipids, has been studied in order
to analyze the influence of the physical state of the bilayer on the aggregation process. Changes in
the size and polydispersity, obtained by dynamic light scattering were used to calculate the critical
aggregation concentrations (c.a.c.) of Ca2+ at which the aggregation of DPPC or F-DPPC was
produced. The results showed different behaviours: at 25 ºC, when the liposomal bilayers are in gel
phase and F-DPPC bilayers are interdigited, DPPC liposomes are more resistant to aggregation
induced by Ca2+ than F-DPPC liposomes. However, at 60 ºC, when liposomes are in liquidcrystalline phase and both bilayers have the same conformation, this difference disappears and c.a.c
coincides for the two types of liposomes. These results also indicate that c.a.c for the two types of
liposomes increases with temperature, suggesting the temperature as a factor to prevent the
liposome aggregation. To compare the experimental results with the theoretical values obtained by
application of DLVO theory, electrophoretic mobilities for liposome dispersions have been
measured.
T = 25 ºC
7500
130
Diameter (nm)
6000
Diameter (nm)
T = 60 ºC
140
4500
3000
1500
120
110
100
90
0
0
250
500
750
1000
time (s)
1250
1500
80
0
250
500
750
1000
1250
1500
time (s)
Figure caption: Stability of F-DPPC liposomes in presence of Ca2+ as a function of temperature (Tc: transition T)
Acknowledgements: This work was supported by the Spanish “Ministerio de Economía y Competitividad”
(Project MAT2011-26330), by the “European Regional Development Fund (ERDF)” and by “Xunta de
Galicia” (Project INCITE08PXIB206030PR).
[1] Toimil, P.; Prieto, G.; Miñones, J. Jr.; Sarmiento, F., Phys. Chem. Chem. Phys. 2010, 12, 13323-13332.
[2] Smith, E. A.; van Gorkum, C. M.; Dea, P. K., Biophys. Chem. 2010, 147, 20-27.
199
P55
Microfluidic synthesis of silicone capsules for encapsulation and release
applications
N. Vilanova1,*, C. Rodríguez-Abreu2, A. Fernández-Nieves3, C. Solans1
1
Institute for Advanced Chemistry of Catalonia, Consejo Superior de Investigaciones Científicas (IQACCSIC), CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain
2
International Iberian Nanotechnology Laboratory (INL), Braga, Portugal
3
School of Physics, Georgia Institute of Technology, Atlanta, USA
*
[email protected]
The production of capsules is attracting a great interest due to their potential applications
in drug delivery. To regulate the release of the drug, it is critical to control the morphology and
polydispersity of the capsules; hence the choice of the strategy to produce them is crucial. Most of
the strategies rely on the use of double emulsions as templates, which can be produced by
numerous methods. Particularly, the use of microfluidic devices to produce double emulsions has
emerged as a useful tool, inasmuch as they enable an accurate control over the morphology and
composition of the emulsions [1]. Although microfluidics have met success in the preparation of
capsules with a wide range of interesting materials [2], the production of silicone capsules is not so
extended despite their attractive properties such as thermal and chemical stability, high
permeability to solvents or biocompatibility [3]. Their limited availability mainly arises from the
high viscosity of the most common silicone precursors, which hampers their manipulation within
the microfluidic device. Here, we report on the production of silicone capsules by means of
microfluidic devices (Fig.a) using double W/O/W emulsions as templates, having a low-viscosity
silicone precursor as the intermediate phase. Stable and monodisperse double W/O/W emulsions,
were successfully produced (Fig.b). The size of the droplets was precisely controlled from 60 to
200 μm by varying the diameter of the capillary tips. The thickness of the shell was also tuned from
2 to 22 μm by adjusting the flow rates of each of the phases. Silicone capsules were obtained by
hardening the intermediate oil phase through a thermal-induced crosslinking reaction, resulting in
the desired monodisperse silicone capsules, hence confirming the templating effect (Fig.c).
Moreover, it was also observed that the mechanical behavior of capsules could be regulated by
varying the size and the shell thickness of the capsules, as well as the elastic modulus of the
silicone network. Besides, it was also possible to encapsulate a hydrophilic molecule within the
capsules. Its release was also studied as a function of the shell thickness, the temperature and the
type of receptor solvent. In all cases the hydrophilic molecule was released in a controlled manner.
a)
b)
c)
100μm
100μm
Figure caption: Optical micrographs of a) the device used to produce the multiple emulsions, b) silicone double
emulsion drops and c) the corresponding silicone capsules.
[1] Utada, A. S., Lorenceau, E., Link, D. R., Kaplan, P. D., Stone, H. A., Weitz, D. A., Science 2005, 308, 537-541
[2] Duncanson, W. J., Lin, T., Abate, A. R., Seiffert, S., Shah, R. K., Weitz, D. A., Lab Chip 2012, 12, 2135-2145
[3] Mark, J. E., Allcock, H. R., West, R. Inorganic Polymers, Second Edition, Oxford University Press, New York,
2005
200
P56
Contact angle hysteresis of commercially pure titanium surfaces functionalized
with organophosphonates
D. Blasco-Avellaneda, A. Y. Sánchez-Treviño, M. A. Rodríguez-Valverde*,
Dept. of Applied Physics, University of Granada, Campus of Fuentenueva, E-18071 Granada (Spain)
*
[email protected]
The implementation of soft matter physics in the design of biomimetic materials is an
exciting and emerging field in material sciences. The chemical tailoring of titanium surfaces
with self-assembled monolayers of organophosphonates enables to reach an optimal range of
biofunctions in a biomaterial [1]. The functionalized surface with this strategy is mechanically
strong and chemically stable. Wettability of a solid surface is sensitive to its chemical
composition, thus contact angle measurements enable to reveal the quality of a chemicallymodified surface. However, there are a range of observable contact angles rather than a unique
value due to contact angle hysteresis. The maximum contact angle (advancing angle) of a
solid-liquid system is usually related with the low-surface energy domains, whereas the
minimum contact angle (receding angle) with the high-surface energy domains. In this work,
we used commercially pure titanium devoted to dental implant and three organophosphonate
molecules with different terminal groups: methyl, phosphonate and carboxyl groups.
Machined titanium surfaces were ultrapolished and next, functionalized as the protocol
reported recently [2]. Contact angle measurements were conducted at room temperature with
MilliQ water using the tilting plate method. The tilting plate provided values of contact angle
hysteresis. We found that the
advancing contact angle of the
chemically-modified
titanium
surfaces reflected the twisted
hydrocarbon chains, the bare regions
of titanium (oxidized) or the methyl
terminal group, accordingly. Instead,
the receding contact angle provided
information about the hydrophilic
terminal groups (phosphonate and
carboxyl). These results were further
validated by AFM, XPS and SEM
(backscattered electron imaging).
Acknowledgements: This study was
supported by the Ministry of Science and Innovation (Project MAT-2010-14800) and by the Junta of
Andalucía (Projects P08-FQM-4325 and P09-FQM-4698). Thanks to J.A. Martín- Pérez for the cutting
and polishing of the titanium samples.
[1] Paz, Y. Self-assembled monolayers and titanium dioxide: From surface patterning to potential
applications, Beilstein J. Nanothechnol. 2011, 2, 845-861.
[2] M. A. Fernández-Rodríguez, M. A. Rodríguez-Valverde and M. A. Cabrerizo-Vílchez. Selective
desorption of organophosphonates on chemically functionalized titanium by Direct Laser
Patterning. Colloids Surf. A: Physicochem. Eng. Aspects 2013, doi:10.1016/j.colsurfa.2013.02.047
201
P57
Self-assembled 2D arrays of Au nanoparticles
Juan J. Giner-Casares1,*, Luis Liz-Marzán1,2
1
Bionanoplasmonics Laboratory, CIC biomaGUNE,
Paseo de Miramón 182, 20009 Donostia, San Sebastián, Spain.
2
Ikerbasque, Basque Foundation for Science, 48011 Bilbao, Spain.
*
[email protected]
The self-assembly of metallic plasmonic nanoparticles (NPs) through the “bottomup” approach is undoubtedly a highly precise tool for obtaining rationally designed assembly
of the NPs into more complex structures. Moreover, such self-organized plasmonic structures
can be effectively integrated into microscale devices [1].
Interfacial self-assembly of metallic nanoparticles at the air/liquid interface offers the
following features: a) experimentally simple, b) no required template, c) scalable to large
areas, d) fine control on the interparticle distance, e) extended order of particle positions and
gaps, and f) applicable to different sizes, shapes, and chemical nature of NPs. The interfacial
spontaneous self-assembly basically consists on the adsorption of NPs at the air/liquid
interface and subsequent transfer to a solid substrate by means of the Langmuir-Schaeffer
method, i.e. lifting of the substrate parallel to the air/liquid interface [2]. In this work, a series
of hydrophobic nanoparticles have been synthesized for their controlled self-assembly onto
solid substrates, see Figure.
Figure caption: Normalized UV-vis spectra of hydrophobic nanoparticles in hexane solution (left
spectrum) and on the subsequent transference to a solid glass support (right spectrum).
Acknowledgements: This work was supported by the ERC Advanced Grant PLASMAQUO (267867)
[1] Alvarez-Puebla, R. A.; Liz-Marzán, L. M., Chem. Soc. Rev. 2012, 41, 43.
[2] Sánchez-Iglesias, A.; Grzelczak, M.; Pérez-Juste, J.; Liz-Marzán, L. M., Angew. Chem. Int. Ed.
2010, 49, 9985.
202
P58
Lipid specificity for the interaction of a novel antimicrobial peptide sp85 with
model membranes
A. Grau-Campistany1,2, M. Pujol1, F. Rabanal2, Y. Cajal1,*
1
Department of Physical Chemistry, Faculty of Pharmacy, Avn. Joan XXIII s/n, 08028 Barcelona, Spain.
Department of Organic Chemistry, Faculty of Chemistry, Martí i Franquès 1, 08028 Barcelona, Spain.
*
[email protected]
2
Sp85 is a synthetic cationic lipopeptide derived from polymyxin B that shows good
activity against Gram negative and Gram positive bacteria. We examined the interaction of
sp85 with negatively charged Langmuir monolayers of POPG and POPE/POPG (6:4), as
models of the Gram positive and Gram negative bacterial cytoplasmic membrane. Kinetics of
insertion at constant area show good levels of peptide binding even at high surface pressures
in the range of the membrane equivalence pressure. Surface pressure isotherms of mixed
lipid/peptide systems are consistent with non-ideal mixing behavior, with negative values of
excess free energy. Sp85 binding to unilamelar lipid vesicles of the same compositions results
in leakage of aqueous contents and lipid mixing. Results are consistent with a mode of action
based on the disruption of the bacterial membrane.
POPG/POPE
POPG
Xsp85 =0.0
Xsp85=0.2
Xsp85=0.4
Xsp85=0.5
Xsp85=0.6
Xsp85=0.8
Xsp85=1.0
S, mN/m
40
30
20
Xsp85 =0.2
Xsp85 =0.4
Xsp85 =0.5
Xsp85 =0.6
30
Xsp85 =0.8
Xsp85 =1.0
20
10
10
0
0
Xsp85 =0.0
40
S, mN/m
50
50
50
100
150
Area, Å2/molecule
200
250
0
0
50
100
150
Area, Å2/molecule
Figure caption: Surface pressure-area isotherms of mixed lipid-sp85 monolayers at various peptide mole
fractions.
Acknowledgements: Funding has been provided by MICINN (CTQ2008-06200), Generalitat de
Catalunya (VAL-TEC 08-1-0016, ACC10), and Fundació Bosch i Gimpera (UB).
[1] Rabanal, F., Rodríguez, M., Garcia, M., Cajal, Y. Patent 2011, WO2011110716
[2] Clausell, A., Busquets, M. A., Alsina, M. A., Cajal, Y. Biopolymers 2004, 75, 480-490.
[3] Clausell, A., Garcia-Subirats, M., Pujol, M., Busquets, M. A., Rabanal, F., Cajal, Y. J. Phys. Chem.
B, 2007, 111, 551-563.
203
P59
Naphthenic bitumen-calcite aggregate wettability at high temperature
F. Guerrero-Barba1,*, J. E. Arellano-Varela2, M. Cabrerizo-Vílchez1,
M. A. Rodríguez-Valverde1
1
Biocolloid and Fluid Physics Group, Department of Applied Physics, University of Granada, Campus of
Fuentenueva, E-18071 Granada, Spain.
2
Petróleos de Venezuela S.A., Av. Libertador, Edif. PDVSA, Torre Este La Campiña, La Campiña,
Caracas (Venezuela)
*
[email protected]
In hot asphalt applications, the thermodynamic adhesion between bitumen and
aggregate depends on the surface tension of bitumen and the bitumen-aggregate contact angle.
Measurement of the physico-chemical bond between bitumen and aggregates should be done
at the same temperatures that the asphalt would be produced at the mixing plant (150-190 ºC).
This is currently not possible with the conventional equipments. In this work, we designed a
new goniometer (contact angle instrument) especially devoted to measure the bitumenaggregate wettability at high temperature.
Migration of endogenous surfactants of bitumen toward the interface [1] and interface
oxidation may be noticeable at high temperatures. We monitored the spreading of heavy
naphthenic bitumen, which is greatly active, on polished substrates of calcite as highly
reactive aggregate. We measured the bitumen contact angle and surface tension in terms of
temperature using the sessile drop method. The surface tension values were validated with the
pendant drop method and a high temperature tensiometer.
Figure caption: Bitumen spreading on calcite substrate (25 μl, 10 min, 80º C)
Acknowledgements: This work was supported by the "Ministerio Español de Ciencia e Innovación"
(project MAT2011-23339) and the "Junta de Andalucía" (projects P08-FQM-4325 and P09-FQM-4698).
[1] Chaverot P., Cagna Alain, Glita Sylvie, Rondelez Francis, Interfacial Tension of BitumenWater
Interfaces. Part 1: Influence of Endogenous Surfactants at Acidic pH. Energy & Fuels pp: 790-798.
204
P60
Surface tensions and activity coefficients for aqueous solutions of
lauryl ether ethoxylates
J. L. López-Cervantes1, J. Gracia-Fadrique1, E. Acosta, E. Calvo2 and A. Amigo2,*
1
Facultad de Química, Departamento de Fisicoquímica, U.N.A.M., México, D.F., 04510, Mexico.
Departamento de Física Aplicada, Facultad de Física, Universidad de Santiago de Compostela, E15782, Santiago de Compostela, Spain.
*
[email protected]
2
Surface tensions for aqueous solutions of Lauryl ether ethoxylates at the temperature
298.15 K were measured using a Lauda drop volume tensiometer. The non-ionic surfactants
analyzed in this work were polyoxyethylene 9 lauryl ether (polidocanol) and polyoxyethylene 4
lauryl ether (brij 30). The surface tension values were used to determine the critical micelle
concentrations (CMC) of the surfactant aqueous solutions as well as to calculate the infinite
dilution activity coefficient of the surfactant following two different models. The first one
combines the first natural nonideal surface equation of state of the Van der Waals type, the Volmer
equation ሺߨሺ‫ ܣ‬െ ‫ܣ‬଴ ሻ ൌ ܴܶሻ, and the Gibbs adsorption equation and is based on the application of
equilibrium conditions between bulk and surface phases. The second one is a group contribution
model that takes into account the mass spectra of the surfactants. The activity coefficient at infinite
dilution for linear surfactants is an additive property that can be expressed as the sum of
hydrophobic and hydrophilic contributions
ߛ ൌ ݊ ߯஼ுమ െ ߯ைு െ ݉ ߯ை஼ுమ ஼ுమ ሺͳሻ
where ݊ represents the number of C-atoms in the hydrocarbon part of the surfactant and ݉ the
number of ethylene oxide (EO) units in the molecule. Considering the molecular weight
distribution of the surfactants we can conclude
ߛ ൌ
σ௠ୀ଴ ݂௠ ൫݊ ߯஼ுమ െ ߯ைு െ ݉ ߯ை஼ுమ ஼ுమ ൯
ሺʹሻ
σ௠ୀ଴ ݂௠
fm
where ݂௠ represents the probability of finding a molecule with m ethylene oxide units in the
surfactant. The Poisson distribution 0.16
was used to fit the experimental
0.14
e OO m
surfactant
molecular
weight
fm
m!
distributions obtained by MALDI0.12
O 7.16 r 0.08
TOF. As an example, Figure shows
the MALDI-TOF mass spectrum of
0.10
C12E4
polyoxyethylene 4 lauryl ether and
C14E4
0.08
the Poisson distribution. Values of
ߛ from group contributions can now
0.06
be determined by using Eq. [2] and
taking into account the presence of
0.04
C14Em in the surfactant molecular
0.02
weight distribution. These values
coincide well with the experimental
0.00
ones (from Volmer’s SEOS).
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
m
Figure caption: MALDI-TOF mass spectrum of polyoxyethylene
4 lauryl ether and the Poisson distribution.
205
P61
Modulation of film morphology at nanoscale by Dipping, Langmuir-Blodgett
and Langmuir-Schaefer
M. D. Merchán*, T. Alejo, and M. M. Velázquez
Departamento de Química Física, Facultad de Ciencias Químicas,
Universidad de Salamanca. 37008 Salamanca, Spain.
*
[email protected]
Dipping, Langmuir-Blodgett (LB) and Langmuir-Schaeffer (LS) have been widely used as
techniques in the preparation of nanomaterials on solids with different purposes. In all cases, the final
target is to deposit some material with a high grade of coverage in a thin film, looking forward some
direct application. Usually the affinity with the solid is not efficient and the resultant films do not have
the desired characteristics. On the other hand, when biomolecules, i.e., proteins, whose biological
activity depends on the molecular arrangements, are immobilized on films, the control on the structure
and orientation of the surface and the properties of molecules adsorbed on the solid wafers become
extremely important [1].
The
zwitterionic
surfactant
3-[(3-cholamidopropyl)-dimethyl-ammonium]-1-propane
sulphonate (CHAPS) is widely used in biochemical applications such as protein solubilization or
disaggregation, and as eluting agent in separation processes to provide selectivity. Recently, the
zwitterionic surfactant CHAPS has been proposed as component of biosensors [2]. One important
characteristic of the biosensors is that the analyte molecules have to be immobilized onto solids to react
with the sensing component; therefore thinner films with a well-defined structure must be obtained to
host the analyte molecules. In a previous work [3] we present a comparison by means of Atomic Force
Microscopy, Optical microscopy and Micro-Raman Spectroscopy between Dipping and LS techniques in
the deposition of CHAPS and Polyethylene imine polymer (PEI)/CHAPS mixtures onto mica. The
hydrodynamic flow of water after its evaporation induces the formation of ring based structures not
available to fabricate biosensors. These patterns are dominating when materials are transferred from the
solution onto mica by Dipping. In contrast, the LS technique provides spherical aggregates and dense
and ordered films.
Self-assembly is established as a very interesting technique in the preparation of many
different types of nanomaterials. Specifically, thin films of soft matter can provide templates for the
fabrication of devices based on QDs in an attempt to achieve sufficiently dispersed nanomaterials in
which the agglomeration of nanoparticles was minimized [4]. In a second part, we have studied the
ability of poly(octadecene-co-maleic anhydride) (PMAO) and a Gemini surfactant [C18H37 (CH3)2 N+ Br
–
-(CH2)2- N+ Br – (CH3)2 C18H37] (18-2-18) to assist in the self-assembly process of CdSe quantum dots
(QDs) at the air-water interface. Results show that, while QD agglomeration is generally inhibited by the
addition of these components to the Langmuir monolayer of QDs, structure of the film transferred onto
mica by the Langmuir-Blodgett method is strongly affected by the dewetting process. Nucleation-andgrowth of holes and spinodal-like dewetting [5] were respectively observed in the presence of either
PMAO or 18-2-18. When PMAO/18-2-18 mixtures were used, both mechanisms were allowed;
nevertheless, even in films prepared with mixtures of low polymer contents, characteristic morphology
from the polymer dewetting route prevailed.
Acknowledgements: The authors thank financial support from ERDF and MEC (MAT 2010/19727). T.A. wishes to
thank European Social Fund and Junta de Castilla y León for the FPI grant. The authors want to thank especially to
Drs J.A. Pérez-Hernández for the AFM measurements and C.L.P.U. (University of Salamanca) for the AFM facility.
We thank to Drs Cirera and Claramunt (University of Barcelona) for the Micro-Raman facility.
[1] Girart, A. P.; Godoy, S.; Blum, L. J. Adv. Colloid Interf. Sci. 2005, 116, 205.
[2] Lee, T.; El-Said, W. A.; Min, J. ; Oh, B. K.; Choi, J. W. Ultramicroscopy 2010, 110, 712.
[3] S. Heisig, M.D. Merchán, M.M. Velázquez, J. Colloid Sci. Biotechnol. 2012, 1, 33-41.
[4] Langner, K. M.; Sevink, G. J. A. Soft Matter 2012, 8, 5102-5118.
[5] Gentili, D., et al Chem. Soc. Rev. 2012, 41, 4430-4443.
206
P62
Implication of a peptide sequence from GB virus C in the inhibition of HIV
fusion peptide
M. Muñoz1,2,3,*, J. Prat1,2,3, M. A. Busquets1,2,3, M. Pujol1,2,3, A. Ortiz1,2,3, O. Domènech1,2,
M. A. Alsina1,2,3, V. Girona1,2,3
1
Physical Chemistry Department. Faculty of Pharmacy. University of Barcelona. Avda Joan XXIII, s/n.
08028 Barcelona. Catalonia. Spain.
2
Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, Martí i Franquès 1,
08028 Barcelona, Spain.
3
Associated Unit to the CSIC Peptides and proteins, physicochemical properties.
*
[email protected]
GB virus C (GBV-C) (formerly known as hepatitis G virus) has recently gained
special attention due to its potential role in the inhibition of AIDS progression [1]. In the
present study we attempted to find the relationship between the physicochemical properties of
the peptide sequence of GBV-C E2 (153-170) (SDRDTVVELSEWGVPCAT) (P45) and the
in vivo results [2]. The peptide shows low surface activity when injected into a buffered saline
subphase pH:7.4 and little penetration into 1,2-dimyristoyl-sn-glycero-3-phosphocholine
(DMPC)/ 1,2-dimyristoyl-sn-glycero-3-phospho-L-serine (sodium salt) (3:2) lipid monolayers
(Figure 1, left). P45 doesn’t affect significantly, FI-HIV penetration into DMPC/DMPS
monolayers [3]. However, fluorescence anisotropy indicates that the peptide inhibits FP-HIV
activity in the hydrophobic core of the bilayer (Figure, right). Atomic force microscopy
(AFM) has confirmed the anisotropy results.
DMPC/DMPS (3/2)
DPH
Control
DM PC/DMPS (3/2)
0.5
p45
FP-HIV-p45
FP-HIV
15
10
5
0
FP-HIV
FP-HIV/P45
P45
0.4
Anisotropy
Pressure increase/mNm -1
20
0.3
0.2
0.1
0
10
20
30
Initial surface pressure/mNm-1
40
0.0
10
15
20
25
30
35
40
Temperature/oC
Figure caption: Left, penetration kinetics of DMPC/DMPS (3:2 molar ratio) lipid monolayers of P45, FP-HIV
and the mixture FP-HIV/P45 (1:2 molar ratio). Right, anisotropy values of 1,6-Diphenyl-1,3,5-Hexatriene
(DPH) fluorescent probe in bilayers of large unilamellar vesicles.
Acknowledgements: This work was supported by Grants CTQ2012-37589-C02-02 from the Ministerio de
Economía y Competitividad and 2009 SGR 560 from the Generalitat de Catalunya.
[1] Zhang, W.; Chaloner, K.; Tillmann, H. L.; Williams, C. F.; Stapleton, J. T. HIV Medicine 2006, 7, 173-180
[2] Herrera, E.; Tenckhoff, S.; Gómara, M. J.; Galatola, R.; Bleda, M. J.; Gil, C.; Ercilla, G.; Gatell, J. M.;
Tillmann, H. L.; Haro, I. J. Med. Chem., 2010, 53, 6054-6063.
[3] Haro, I.; Gómara , M. J.; Galatola, R.; Domènech, O; Prat, J.; Girona, V.; Busquets, M. A. Biochim. Biophya.
Acta 2011, 1808, 1567–1573.
207
P63
Study of the Behavior of Poly(NIPAM) Microgels under Ionic Specific
Conditions: Electrokinetic and AFM measures
Leonor Pérez-Fuentes1,*, Carlos Drummond2 and Delfi Bastos-González1
1
Biocolloid and Fluid Physics Group, Department of Applied Physics, University of Granada,
Granada 18071 (Spain)
2
CNRS, Centre de Recherche Paul Pascal (CRPP), Bordeaux (France)
*
[email protected]
Ionic specificity, also known as Hofmeister effects, has been studied since Hofmeister
discovered them in 1888 [1]. These effects are connected with the ability of different ions to
modify interfaces properties. In spite of many works about this issue, there is no a theory that
provides a complete explanation of the origin of Hofmeister effects. According to previous
researches [2,3], hydrophobic or hydrophilic character of surfaces is crucial to explain ionic
specificity.
In order to deepen in the origin of Hofmeister phenomena and their connection with
reversal charge and hydrophobic effect [4], we have chosen a very sensitive system to ionic
medium conditions, such as poly(NIPAM) microgels [5]. These microgels are formed by polymer
poly(N-isopropyl acrylamide), with extraordinary properties of solvency, which are highly
dependent on physicochemical conditions such as temperature, salt concentration and pH.
Therefore, microgels experiment a volume phase transition caused by temperature change, from
swollen state (hydrophilic character) to collapsed state (hydrophobic character). In particular, for
poly(NIPAM) the lower critical solution temperature (TLCS) is about 32 ºC. This TLCS is very
sensitive to ionic specific effects.
We have performed an experimental study with different hydrophobic or chaotropes
anions (tetraphenylborate, tetraphenylarsonium and thiocyanate) and two poly(NIPAM) microgels
synthesized in our labs, one negative and one positively charged. Experiments were carried out
with nano-zeta and AFM devices. AFM in liquid environment is an excellent tool to study in-situ
the properties of responsive surfaces [6]. We have studied, with this tool, swelling-to-collapse
transition of the cationic and anionic poly(NIPAM) microgels adsorbed on inverse-chargedsubstrate. We observed that swelling process and adsorption properties of microgels are modified
by the ionic environment. On the other hand, we also measured electrophoretic mobility with the
different ions under identical conditions that in AFM studies. The combination of both techniques
has been found very useful in order to explain the adsorption of chaotropes ions to the
poly(NIPAM) interface and hence to improve the understanding of ionic specificity in colloidal
systems.
Acknowledgements: The authors acknowledge the financial support from projects MAT2009-13155-C04-02,
MAT2012-3670-C04-02 (Ministerio de Educación y Cultura (Spain)), P10-CTS-6270 (Junta de Andalucía)
and CEIBioTic 20F12/16.
[1] Hofmeister, F., Arch.Pathol. 1888, 24, 247.
[2] López-León, T.; Santander-Ortega, M. J.; Ortega-Vinuesa, J. L.; Bastos-González, D., J. Phys. Chem. C.
2008, 112, 16060.
[3] Peula-García, J. M.; Ortega-Vinuesa, J. L.; Bastos-González, D., J. Phys. Chem. C. 2010, 114, 11133.
[4] Calero, C.; Faraudo, J.; Bastos-González, D., J. Am. Chem. Soc. 2011, 133, 15025.
[5] López-León, T.; Elaïssari, A.; Ortega-Vinuesa, J. L.; Bastos-González, D., ChemPhysChem. 2007, 8, 148.
[6] Bousquet, A.; Ibarboure, E.; Drummond, C.; Labrugère, C.; Papon, E.; Rodriguez-Hernandez, J.,
Macromolecules. 2008, Vol. 41, No. 4, 1053.
208
P64
Properties of chitosan-insulin complexes obtained by an alkylation reaction on
chitosan
Emmanuel Robles1, Josué Juárez3,*, Manuel Alatorre-Meda4, María. G. Burboa2,
Pablo Taboada4, Víctor Mosquera4, Miguel A. Valdez3
1
Departamento de Investigación en Polímeros y Materiales,
Departamento de Investigaciones Científicas y Tecnológicas,
3
Departamento de Física, Universidad de Sonora, Rosales y Transversal,
83000 Hermosillo, Sonora, México
4
Departamento de Física de la Materia Condensada, Facultad de Física,
Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
*
[email protected]
2
Recently we have investigated the influence of hydrophobization of chitosan on the
in vivo release insulin of insulin-chitosan nanopartilces [1]. In this work, we investigate the
influence of chitosan hydrophobization on the formation, thermodynamic and surface tension
properties of insulin-chitosan complexes. We use an alkylation procedure to insert 12 carbon
chains along the chitosan macromolecule with a final 5, 10 and 50 % substitution degree.
Nuclear magnetic resonance (NMR) and infrared spectroscopies (IR) were used to evaluate
the success and extent of the hydrophobization procedure. The size of bare polymer and
polymer-insulin complexes were evaluated by dynamic light scattering (DLS). DLS data
demonstrated that complexes made with hydrophobized chitosans possess smaller sizes than
the ones obtained with unmodified chitosan. Isothermal titration calorimetry (ITC) was used
to determine the type and extent of the existing interactions between the different constituting
components of insulin-hydrophobized chitosan complexes. By surface tension, diffusion
coefficients at the air-water interface and ITC experiments on different insulin/chitosan
proportions we demonstrate that around 34, 25, 25 and 60 insulin molecules saturate 0 %, 5 %,
10 % and 50 % hydrophobized chitosans, respectively. Surface tension experiments at the airwater interface of insulin-chitosans complexes demonstrate that insulin molecules on
unmodified chitosan increases hydrophobicity, which demonstrates mainly electrostatic
interaction, on the contrary insulin-hydrophobized chitosans interaction lowers the
hydrophobicity due to the insulin alkyl chains interaction.
[1] Effects of the hydrophobization on chitosan-insulin nanoparticles obtained by an alkylation reaction
on chitosan. Robles, E.; Villar, E.; Alatorre-Meda, M; Burboa, M. G.; Valdez, M. A.; Taboada, P.;
Mosquera, V. J. Appl. Polym. Sci., 2012, DOI: 10.1002/APP.38870
209
P65
From 2D to 3D at the Air/Water Interface: The Self-Aggregation of the Acridine
Dye in Mixed Monolayers
Carlos Rubia-Payá1,*, Eugenio Jimenez-Millán1, Juan J. Giner-Casares1, Gerald Brezesinski2,
María T. Martín-Romero1, and Luis Camacho1.
1
Department of Physical Chemistry and Applied Thermodynamics, University of Córdoba, Campus de
Rabanales, Edificio Marie Curie, Córdoba, Spain E-14014.
2
Department of Interfaces, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476,
Germany
*
[email protected]
The formation of well-defined supramolecular structures in the nanoscopic scale is a
fundamental step in nanotechnology. The fine control of the layer-by-layer growth of the
supramolecular assemblies at interfaces is most desirable. The collapse of a mixed monolayer
composed of two surfactants in equimolar ratio: the organic dye N-10-dodecyl acridine (DAO)
and stearic acid (SA) is analyzed herein. The collapse process of the DAO:SA mixed
monolayer has been monitored using surface pressuremolecular area (-A), surface potential
isotherms, UV-visible reflection spectroscopy, Polarization-Modulated Infrared ReflectionAbsorption Spectroscopy (PM-IRRAS), Brewster Angle Microscopy (BAM), and
synchrotron-based in situ X-ray Reflectivity (XRR) measurements. The collapse of the
DAO:SA mixed monolayer leads to an ordered trilayer.
The growth of anisotropic 2D domains of micrometric
size is observed during the formation of the trilayer,
relating to the ordering of the acridine polar
headgroups. The trilayer is organized with the first and
third monolayers displaying the polar headgroups
pointing to the aqueous subphase, whereas the
intermediate layer display the polar headgroups
pointing to the air. The trilayer is stabilized by the
strong self-aggregation acridine dye group of the DAO
molecule. The controlled transition from a monolayer
to a trilayer described herein is proposed as a model for
further interfacial supramolecular structures of tunable
thickness comprising organic dyes.
Figure caption: BAM image of Hexagonal domains, and Schematic model of the trilayer formed during
the collapse process. DAO molecules are red colored, and SA molecules are blue colored.
Acknowledgements: Juan J. Giner-Casares acknowledges the Alexander von Humboldt foundation for a
postdoctoral grant. We thank HASYLAB at DESY, Hamburg, Germany, for beamtime and Dr. Bernd
Struth for excellentsupport and assistance. This work was supported by the Max Planck Society. The
authors thank the Spanish CICYT for financial support of this research in the framework of Project
CTQ2010-17481 and also thank the Junta de Andalucía (CICyE) for special financial support P08-FQM4011 and P10-FQM-6703.
[1] Pérez-Morales, M.; Pedrosa, J. M.; Martín-Romero, M. T.; Möbius, D.; Camacho, L. J. Phys. Chem.
B 2004, 108, 4457-4465
[2] Giner-Casares, J. J.; de Miguel, G.; Perez-Morales, M.; Martin-Romero, M. T.; Camacho, L.; Muñoz,
E., J. Phys. Chem. C 2009, 113, 5711-5720.
210
P66
In-situ monitoring of biomimetic hydroxyapatite growth on functionalized
titanium surfaces: An AFM study
A. Y. Sánchez-Treviño*, M. A. Fernandez-Rodríguez, M. A. Rodríguez-Valverde and
Dpto. Física Aplicada, Facultad de Ciencias, Campus Fuentenueva s/n,
Universidad de Granada, E-18071 Granada, Spain.
*
[email protected]
In dental implantology, a satisfactory short-term response of the implants may allow for a rapid
healing and earlier loading. Biomimetic strategies intend to accelerate the bone growth on implant
surfaces. A promising approach (simple and cost-effective) is the growth of artificial hydroxyapatite
(HA) on chemically modified titanium surfaces immersed in a simulated body fluid (SBF) upon
physiological conditions [1-3]. Although the biomimetic coating on titanium implants must reach certain
mechanical properties with long times of SBF incubation, the nucleation and the subsequent growth of
bone-like apatite on the titanium surface begin rapidly. The final properties of the biomimetic HA layer
might be partly dictated by the first underlying layer. In this study, we continuously monitored the early
kinetics (up to 8 h) of HA growth on a titanium surface with Atomic Force Microscopy (AFM,
Nanoscope IV, Veeco). For this study, we used ultra-polished metallic titanium surfaces (ASTM grade
II) activated separately with two molecules of organophosphonates (phosphonate and carboxyl
functional groups). A previous nucleation of nascent calcium phosphate, deposited by a fast precipitation
method [4], was performed to reduce the time of biomimetic HA growth. Further, we concentrated the
SBF up to 1.5 times regarding the standard recipe [5]. The growth of biomimetic coating was conducted
inside the AFM liquid cell, filled with SBF and maintained at 37ºC. Each surface was imaged in tapping
mode using standard silicon cantilevers (Veeco probes, nominal spring constant 20-80 N/m), refreshing
the SBF solution each 2 h. The results show that the well-known globular morphology of apatite layers
was revealed in 7 h, being much more uniform in height over the titanium surfaces modified with
organophosphonates than over the unmodified (hydroxylated) surfaces (peak-to-valley distance = 1014
nm).
Figure caption: AFM height images of HA coatings developed on titanium surfaces after 7 h: (a) unmodified
(hydroxylated) surface and (b) carboxyl-terminated surface.
Acknowledgements: This study was supported by the Ministry of Science and Innovation (Project MAT-2010-14800)
and by the Junta of Andalucía (Projects P08-FQM-4325 and P09-FQM-4698). Thanks to J.A. Martín- Pérez for the
cutting and polishing of the titanium samples.
[1] Dapeng, L. Hydroxyapatite formed on titanium via a self-assembled monolayer and its in-vitro behaviour. Thesis
(M. Eng. Sc.) University of Adelaide, School of Chemical Engineering, 2005.
[2] Xia, W.; Lindahl, C.; Lausmaa, J.; Engqvist, H. Biomimetic Hydroxyapatite Deposition on Titanium Oxide
Surfaces for Biomedical Application. Advances in Biomimetics. InTech, 2011.
[3] Wu, J.; Hirata; I.; Zhao, X.; Gao, B.; Okazaki, M.; Kato, K., J. Biomed. Mater. Res. Part A 2013.
[4] Koichi, K.; Yoshihiro, E.; Yoshito, I., J. Biomed. Mater. Res. 1996, 32, 687-691.
[5] Jalota, S.; Bhaduri, S. B.; Tas, A. C., J. Mater. Sci.: Mater Med. 2006, 17, 697.
211
P67
Using artificial intelligence based tools for predicting the CMC
of non-ionic surfactants
G. Astray1,2,*, O. A. Moldes1, M. A. Iglesias-Otero1 and J. C. Mejuto1
1
Department of Physical Chemistry, Faculty of Sciences, University of Vigo, Ourense, Spain.
2
Faculty of Law, International University of La Rioja, Logroño, Spain.
[email protected]
Surfactants are compounds that reduce the surface tension of the medium and that can
form aggregates such as vesicles, foams, gels, micelles, aerosols, etc. [1]. The Critical Micelle
Concentration (CMC) is the range concentration above which the micelles are formed; this
property is fundamental to study of behaviour of surfactants [2]. CMC can be studied by different
techniques such as stopped flow, temperature-jump (T-jump), fluorescence probes, light scattering
or refractometry, inter alia [1,3,4]. All these experimental techniques require economic resources,
reagents and long-time [1], to avoid this; we developed a model based on Artificial Neural
Networks (ANN) to obtain values of CMC of non-ionic surfactants. All data required to develop
the model were taken from the literature [4,5]. The topological descriptors used as input variables
to determinate CMC were originally calculated by Jalali-Heravi et al. [4].
The best ANN model consists in an input layer with seven neurons, only one intermediate
layer with fourteen neurons and one neuron in the output layer [1]. The training cases used to
implemented the ANN model has a RMSE of 0.076 (R2= 0.995) and the validation cases, used to
verified the good prediction power of the model, has a 0.100 (R2= 0.996). These errors correspond
to 1.62% for training phase and 2.47% of error for validation phase [1]. These results represent an
improvement 66.02% compared with the MLR model proposed by Jalali-Heravi et al. [4] (Figure).
These results indicate that ANN model has a good predictive capability for values of CMC.
Figure caption: Experimental log CMC (CMCexp) versus predicted (CMCpred) for training values ({) and
testing values (z) by ANN model [1] (left) versus Jalali-Heravi et al. [4] (right).
Acknowledgements: G. Astray thanks Ministerio de Educación of Spain for a FPU grant P.P. 0000 421S
14006. M.A Iglesias-Otero and O. Moldes acknowledges Univ. de Vigo for their grant P.P. 00VI131H64103.
[1] Astray, G.; Iglesias-Otero, M.A.; Moldes, O.A.; Mejuto, J.C., Tenside Surfactants Deterg. 2013, 50, 118-124.
[2] Domínguez, A.; Fernández, A.; González, N.; Iglesias, E.; Montenegro, L., J. Chem. Educ. 1997, 74, 1227-1231.
[3] Patist, A.; Oh, S.G.; Leung, R.; Shah, D.O., Colloids Surf. A: Physicochem. Eng. Aspects 2001, 176, 3-16.
[4] Jalali-Heravi, M.; Konouz, E., Quantitative Structure-Activity Relationships 2000,19,135-141.
[5] Van Os, N.M.; Haak, J.R.; Rupert, L.A.M., Physico-Chemical Properties of Selected Anionic, Cationic and
Nonionic Surfactants. Elsevier: Amsterdam, 1993.
212
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A numerical tool for analyzing equilibrium capillary rise
D. Blasco-Avellaneda1,*, A. Amirfazli2, M. A. Rodríguez-Valverde1,
M. A. Cabrerizo-Vílchez1.
1
Deptartment of Applied Physics, University of Granada, Campus of Fuentenueva, E-18071 Granada
2
Department of Mechanical Engineering,York University, Toronto, ON, M3J 1P3
*
[email protected]
The continued miniaturization in the integrated circuits industry presents a problem of
increasing importance: the pattern collapse [1, 2]. To understand the pattern collapse
phenomenon better, a numerical model based on Surface Evolver was developed to predict the
equilibrium shape and height of a meniscus confined between two plates in capillary regime
(when surface tension dictates the meniscus shape) [3]. Such model also has applications in
fiber and hair wetting. We obtained a simple and robust model validated with well-established
laws (Jurin’s law, Laplace equation). We tackled a wide range of system features and
configurations: plate-to-plate distance, plate width, contact angle plate, plates composed of
different material, inclined plates, angle between plates, limiting plate height; with all results
contrasted with the theory and validated by it. Consequently, our approach is able to be
adapted to the specific characteristics of the various issues raised in the unsolved problem of
pattern collapse.
(a)
(b)
(c)
Figure caption: (a) Water meniscus confined between two vertical plates separated by 1 l0 and with a
width10 l0. (b) Dimensionless equilibrium height of meniscus in terms of dimensionless plate-to-plate
distance for two contact angles (17º and 45º). (c) Dimensionless capillary pressure at the meniscus apex
in terms of dimensionless equilibrium height for a contact angle equal to 17º and different plate-to-plate
distances (d l0).
Acknowledgements: This work was supported by the “Ministerio Español de Ciencia e Innovación”
(project MAT2011-23339) and the “Junta de Andalucía” (projects P08-FQM-4325 and P09-FQM-4698)
[1] Collapse of patterns with various geometries during drying in photolithography: numerical study.
Chini, S. F., Amirfazli, A., J. Micro/Nanolithogr., MEMS, and MOEMS 2012, 11, 033003.
[2] Understanding pattern collapse in photolithography process due to capillary forces. Chini, S. F.,
Amirfazli, A., Langmuir 2010, 16, 13707-13714.
[3] Capillary rise in a microchannel of arbitrary shape and wettability hysteresis loop. Wang, Z., Chang,
C.C., Hong, S.J., Sheng, Y.J., Tsao, H.K., Langmuir 2012, 28, 1691716926.
213
P69
Self-Assembly of a long-chain ionic surfactant at low concentrations: a
simulation study
Javier Burgos, Conxita Solans and Alessandro Patti*
Institute of Advanced Chemistry of Catalonia (IQAC-CSIC) and
CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN)
Jordi Girona 18-26, 08034 Barcelona, Spain.
*
[email protected]
Above the critical micellar concentration (cmc), surfactants with the right
solvophobic/solvophilic ratio self-assemble and form aggregates. At the cmc, the
concentration of free surfactants in solution stops increasing, whereas that of aggregates starts
to increase. Depending on several conditions, such as temperature, solvent, electrolytes,
cosurfactants, and on the surfactant architecture as well, the cmc can vary rather significantly
as well as the shape and size of micelles at equilibrium [1]. Due to their large applications in
formulation chemistry and in nanotechnology as templates for the synthesis of advanced
materials, the principles controlling self-assembly and micellization of surfactants are of
fundamental relevance. In the last decades, computer simulations have played a key role in
determining the phase and aggregation behavior of many different amphiphilic systems, via
the implementation of both rigorous atomistic [2,3] and coarse-grained (CG) [4-6] models.
In this work, by performing lattice Monte Carlo (MC) simulations, we investigate the
self-assembly of a cationic surfactant (ricinoleamidopropyltrimonium methasulfate) which
finds large applications in formulation chemistry and, more specifically, in cosmetics. We
apply an efficient CG model [6] where the surfactant molecules are represented as linear
chains of connected beads in a three-dimensional lattice network. The headgroups, carrying
the charge, are neutralized by a number of monovalent counterions. The charged groups
interact via a Coulombic potential and a hard core repulsion, whereas neutral tail-tail
interactions are only established between close neighbors, defined by the lattice coordination
number. All the lattice sites are occupied by the surfactant or by the solvent. By tuning the
mutual interaction between the solvophilic and solvophobic groups, and that between them
and the solvent, we are able to observe aggregation and formation of micelles. We compute
the cmc, the density distribution profiles in the micelles, their aggregation number, and the
distribution of the counterions. Our results are compared with experimental results carried out
in our laboratory.
Acknowledgements: Spanish Ministry of Science and Innovation, grants CTQ2011-29336-C03-01 and
JCI-2010-06943. Generalitat de Catalunya, Grant 2009SGR-961
[1] J. N. Israelachvili, Intermolecular and Surface Forces, Academic Press, 2nd Ed., 1998.
[2] M. Jorge, J. Mol. Struct.: THEOCHEM, 2010, 946, 88-93.
[3] S. Pal, B. Bagchi and S. Balasubramanian, J. Phys. Chem., 2005, 109, 12879.
[4] A. Patti, A. D. Mackie and F. R. Siperstein, Langmuir, 2007, 23, 6771-6780.
[5] A. Patti, R. Ramsch and C. Solans, J. Phys. Chem. B, 2012, 116, 2687-2695.
[6] D. W. Cheong and A. Z. Panagiotopoulos, Langmuir, 2006, 22, 4076-4083.
214
P70
Balance Hidrofílico-Lipofílico HLBTR. Escala Termodinámica
J. Gracia-Fadrique1,*, J. L. López-Cervantes1, F. D. Sandoval-Ibarra1 and A. Amigo-Pombo2
1
Facultad de Química, Departamento de Fisicoquímica, U.N.A.M., México, D.F., 04510, México.
Departamento de Física Aplicada, Facultad de Física, Universidad de Santiago de Compostela, E15782, Santiago de Compostela, España.
*
[email protected]
El acoplamiento del potencial químico no ideal de la superficie, proveniente de la ecuación de
Volmer, S$$ RT, y del potencial químico no ideal de la fase líquida, proporciona una relación
lineal en presión superficial, en el intervalo menor o igual a la concentración micelar crítica [4].
§S* ·
(1)
ln ¨ ¸ zo 1 S * ln J f ;
x d xcmc
© x ¹
2
donde S* corresponde a la presión reducida o relación entre la presión superficial y la presión superficial
máxima, Sm, la pendiente z0 y el coeficiente de actividad a dilución infinita J. La ecuación (1) presenta
como ventajas, además del comportamiento lineal, condiciones de frontera que contienen
respectivamente la energía estándar de adsorción y la energía estándar de micelización; evaluada en
saturación el coeficiente de actividad se identifica como el reciproco de la concentración micelar crítica.
Ya que la periodicidad por contribución de grupos está presente en régimen diluido (Traube; RT ln3) y la
energía estándar de adsorción contiene a la micelización, la ec. (1) explica entonces la reinterpretación
del coeficiente de actividad a dilución infinita mediante contribuciones hidrofílicas OHFIL e hidrofóbicas
OHFOB [2-3].
(2)
ln J f ¦ ln OHFOB ¦ ln OHFIL
El coeficiente de actividad a dilución infinita, en una serie homóloga de tensoactivos,
cuantifica termodinámicamente el efecto hidrofóbico en función de la temperatura, disolvente y terceros
componentes en disolución; propiedades no presentes en las escalas convencionales del HLB. En
términos de propiedades funcionales de un tensoactivo, es conveniente proponer una relación porcentual
en una escala fundada en las contribuciones termodinámicas moleculares a la no idealidad y con una
mayor sensibilidad a las variaciones hidrofílicas, de donde surge la expresión correspondiente del
balance hidrofílico-lipofílico termodinámico (HLBTR)
ln O
T (3)
HLBTR ¦ fHFIL
u 100
ln J T 20
50
a
n-Alcohol
p-t-Octilfenol etoxilado
b
40
12
HLBTR
HLBTR
16
8
30
20
n-Alcohol etoxilado
4
Nonilfenol etoxilado
10
20
30
número de óxidos de etileno
40
10
4
6
8
10
12
14
número de carbones
Figura: a) HLBTR para el nonilfenol etoxilado y el p-t-orctilfenol etoxilado en función del número de óxido de
etileno. b) HLBTR para los n-alcoholes y n-alcoholes etoxilado en función del número de carbonos.
[1] Viades-Trejo, J.; Abascal-González, D. M.; Gracia-Fadrique, J., J. Surfact. Deterg. 2012, 15, 637-645
[2] Calvo, E.; Bravo, R.; Amigo, A.; Gracia-Fadrique, J., Fluid Phase Equilib., 2009, 282, 14-19
[3] Viades-Trejo, J.; Gracia-Fadrique, J., Fluid Phase Equilib. 2008, 264, 12-17
[4] Viades-Trejo, J.; Amigo, A.; Gracia-Fadrique, J., Fluid Phase Equilib. 2006, 250, 158-164
215
P71
Computational tools for forecasting the effect of small organic molecules upon
electric percolation of AOT-based microemulsions
Ó. A. Moldes1,*, G. Astray1,2, A. Cid3 and J.C. Mejuto1
1
2
Faculty of Law, International University of La Rioja, Logroño, Spain
3
Chemistry Department, REQUIMTE-CQFB, University Nova of Lisbon, 2829-516 Monte de Caparica,
Portugal.
*
[email protected]
Microemulsions are ternary systems composed of droplets of a dispersed phase distributed
in a continuous phase and separated of it by a surfactant film in a dynamic structure. A low
conductivity is characteristic of AOT-based w/o microemulsions, but also the electrical percolation
phenomenon [1]. This consist in a sharp increase observed in conductivity when either temperature
or volume fraction of the dispersed phase reach a specific critical value. Electrical percolation
depends strongly on the rigidity of the surfactant film. A softer film promotes shocks among
microdroplets that ultimately allow charge transport, while a stiffer film reduces likelihood of
effective shocks, decreasing and increasing percolation threshold temperature respectively.
Presence of different molecules as additives, through their different solubility on microemulsion
components, modifies rigidity of the surfactant film and consequently, percolation threshold.
Although there are some theories to explain percolative behavior, none of them consider
effects of additives. Considering this, the point of this work has been to develop a simulation tool
for percolative behavior of AOT-based microemulsions (w/o AOT/iC8/H2O microemulsions) under
the influence of small organic molecules as additives. Simulations have been based on multilayer
perceptrons, one of the most famed artificial neural network architectures [2].
Networks have been designed with three inputs (W value of microemulsions, additive
concentration and log P). Network with better accuracy can predict percolation temperature of a
microemulsion
with
a
specific concentration of
additive. That network is
composed of three input
neurons, two neurons in a
hidden layer and one output
neuron.
R-values
for
training and validation have
been 0.9251 and 0.9719
respectively. The most
relevant variable for this
model is log P.
Figure caption: Scheme of the obtained multilayer perceptron.
Acknowledgements: Dr. Astray thanks to Ministry of Education for his FPU contract (PP 421S 14 006 0000),
Dr. Cid thanks to MCTES-FCT (Portugal) his post-doctoral grant (SRFH/BPD/78849/2011), while Moldes
thanks University of Vigo for a grant.
[1] García-Río, L; Mejuto. J.C.; Pérez-Lorenzo, M.; Rodríguez-Álvarez, A.; Rodríguez-Dafonte, P., Langmuir
2005, 21, 6259-6264.
[2] Hornik, K.; Stinchcombe, M.; White, H., Neural Networks 1989, 2, 359-366
216
P72
Does incubation time affect the formation of the protein corona?
Ana L. Barrán-Berdón1,2,*, Daniela Pozzi2, Giulio Caracciolo2, Anna Laura Capriotti3,
Giuseppe Caruso3, Chiara Cavaliere3, Anna Riccioli4, Sara Palchetti4 and Aldo Laganà3
1
Departamento de Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de
Madrid, 28040-Madrid, Spain
2
Department of Molecular Medicine, “Sapienza” University of Rome, Viale Regina Elena, 291, 00161,
Rome, Italy
3
Department of Chemistry, “Sapienza” University of Rome, P.le A. Moro 5, 00185 Rome, Italy
4
Dipartimento di Scienze Anatomiche, Istologiche, Medico-Legali e Dell'apparato Locomotore,
“Sapienza” University of Rome, P.le A. Moro 5, 00185 Rome, Italy
*
[email protected]
When administered in vivo nanoparticles (NP) interact with plasma proteins and are
covered by a rich protein layer, the “protein corona”, whose composition changes in time due
to continuous protein binding and unbinding events. The most relevant implication is that the
identity of the bare NP is rapidly lost, and the biological behavior is controlled by its timeevolving protein corona [1-3]. In this study we investigate the time evolution of the protein
corona associated with lipid nanoparticles whose lipid envelope is a binary mixture made of
the cationic lipid 3E->N-(N´,N´-dimethylaminoethane)-carbamoyl@ (DC-Chol) and the
zwitterionic lipid dioleoylphosphatidylethanolamine (DOPE) in the range between 1 min and
1 hour. Exposing DC-Chol–DOPE lipid vesicles to human plasma, a clear evolution of the
associated protein corona over time was observed. Mass spectrometry of the digested protein
corona revealed apolipoproteins as the most abundant component, which suggests an
improved biocompatibility and indicates novel opportunities for targeted drug delivery. Given
the abundance of apolipoproteins in the corona of DC-Chol–DOPE/HP complexes our thought
was to target PC3 prostate carcinoma cell lines that constitutionally express high levels of the
alipoprotein receptor. Combining laser scanning confocal microscopy experiments with flow
cytometry we could demonstrate that DC-Chol–DOPE/HP complexes enter PC3 cells by a
receptor-mediated endocytosis.
[1] Casals, E.; Pfaller, T.; Duschl, A.; Oostingh, G. J.; Puntes, V., ACS Nano 2010, 4, 3623-3632.
[2] Lundqvist, M.; Stigler, J.; Cedervall, T.; Berggård, T.; Flanagan, M. B.; Lynch, I.; Elia, G.; Dawson,
K. A., ACS Nano 2011, 5, 7503-7509.
[3] Mahon, E.; Salvati, A.; Baldelli Bombelli, F.; Lynch, I.; Dawson, K. A., J. Control. Release 2012,
161, 164-174
217
P73
The effect of fluorinated cholesterol derivative on the stability and physical
properties of cationic DNA vectors
A. Martín-Molina1,*, D. Paiva2, I. Cardoso3, M. Quesada-Pérez4, M. d. C. Pereira2 and
S. Rocha2
1
Department of Applied Physics, University of Granada, Spain.
LEPAE, Department of Chemical Engineering, University of Porto, Portugal.
3
Molecular Neurobiology, IBMC – Instituto de Biologia Molecular e Celular and Escola Superior de
Tecnologia da Saúde do Porto, Portugal.
4
Department of Physics, University of Jaén, Spain.
*
[email protected]
2
Liposomes of the cationic lipid DOTAP (1,2-dioleyl-3-trimethylammonium-propane)
and the fluorinated cholesterol derivative, heptafluorocholesterol (F7-CHOL), were tested at
the molar ratios of 1:1 for DNA compaction and transfection. Their properties were correlated
to the characteristics of the well-known system DOTAP and cholesterol (CHOL). The mass
lipid/DNA (L/D) ratios at the isoelectric point were within the ranges 3 – 4 for
DOTAP:CHOL and 4 – 5 for DOTAP:F7-CHOL, as determined by electrophoretic mobility
measurements. These results and the ethidium bromide fluorescence intercalation assays
confirmed that more DOTAP:F7-CHOL liposomes are needed to compact the same amount of
DNA as DOTAP:CHOL. The phase diagrams of aggregation and re-entrant condensation
phenomena obtained by phenomenological theory support this conclusion and established also
that the liposome-DNA binding is stronger in the case of DOTAP:F7-CHOL/DNA system.
The stability rates of both liposomes in the presence of DNA were similar as well as the
transfection efficiencies, which support the application of heptafluorocholesterol as helper
lipid in cationic liposomes for DNA delivery [1].
Acknowledgements: This work was financed by FCT and FEDER through COMPETE (projects
PTDC/QUI-BIQ/102827/2008 and PTDC/QUI-BIQ/118076/2010), by MICINN of Spain (projects
MAT2012-36270-C04-02 and -04), by Junta de Andalucía (project P09-FQM-4698) and CEIBioTic
Granada (project 20F12/16). D. Paiva thanks FCT for a PhD fellowship (SFRH/BD/45384/2008).
[1] Paiva, D.; Martin-Molina, A.; Cardoso, I.; Quesada-Perez, M.; Pereira, M. d. C.; Rocha, S. Soft
Matter 2013, 9, 401-409
218
P74
BIONANOPARTICLES
Aintzane Pikabea, Garbiñe Aguirre, Ainara Imaz, Jose Ramos, and Jacqueline Forcada*
POLYMAT, Bionanoparticles Group
Department of Applied Chemistry, UFI 11/56
Faculty of Chemistry, University of the Basque Country UPV/EHU
Apdo. 1072, Donostia-San Sebastián, 20080, Spain
*[email protected]
The challenges in the production of new nanoparticles for bio-applications are related
to the necessity or bio-applications in which they could be used. But to the moment, an in
deep study on the possibilities of biocompatible and also biodegradable nanoparticles directed
to bio-applications (diagnosis, drug and gene delivery, among others) is in its infancy. On the
one hand, environmental sensitive soft nanoparticles in the colloidal range offer unique
advantages for biotechnological applications due to their tunable size from nanometers to
micrometers, a large surface area for multivalent bioconjugation (a reaction forming a stable
covalent link between at least two biomolecules), and an internal network useful for
incorporation of biomolecules or drugs. However, the development of new synthesis strategies
to incorporate functional groups (specific ligands) inside biocompatible nanoparticles will be
one of the challenges to be overcome for using this type of nanomaterial for theranostic
purposes. On the other hand, works devoted to the hybrid technology are of great interest and
stimuli responsive hybrid colloids containing organic and inorganic components are a matter
of study due to their attractive properties for pharmaceutical and biomedical applications. In
this way, future work on biocompatible polymers-based hybrid nanoparticles will be directed
to produce new families of hybrid nanoparticles for using in therapeutic treatments requiring
the use of magnetic fields.
Concerning future perspectives, although a significant progress in the understanding
of the general behavior of hard, hybrid, and soft nanoparticles for bio-applications has been
achieved in the last decade, a lot of interesting work remains to be done on new specific
bionanoparticles. Our research lines can be summarized as follows:
x
x
x
x
Synthesis and characterization of hard, hybrid, and soft nanoparticles for bioapplications.
Colloidal and polymeric characterizations of bionanoparticles.
Modeling the heterogeneous polymerization processes to produce hard, hybrid, and
soft nanoparticles for bio-applications.
In vitro preliminary bio-applications using hard, hybrid, and soft bionanoparticles.
Acknowledgements: This work has been supported by the Spanish Plan Nacional de Materiales
(MAT2012-36270-C04-01).
[1] Aguirre, G.; Ramos, J.; Forcada, J., Soft Matter 2013, 9, 261-270.
[2] Ramos, J.; Imaz, A.; Forcada, J., Polymer Chemistry 2012, 3, 852-856.
[3] Ramos, J.; Forcada, J., Langmuir 2011, 27,7222-7230.
[4] Ramos, J.; Imaz, A.; Callejas-Fernández, J.; Barbosa-Barros, L.; Estelrich, J.; Quesada-Pérez, M.;
Forcada, J., Soft Matter 2011, 7, 5067-5082.
[5] Costoyas, A.; Ramos, J.; Forcada, J., J. Polym. Sci. Part A: Polym. Chem. 2009, 47, 6201-6213.
[6] Costoyas, A.; Ramos, J.; Forcada, J., J. Polym. Sci. Part A: Polym. Chem. 2009, 47, 935-948.
219
P75
Synthesis and characterization of degradable and biocompatible poly(E-amino
ester)-DNA complexes
Azahara Rata-Aguilar1, Juan L. Ortega-Vinuesa1,*, Ana B. Jódar-Reyes1, Antonio MartínRodríguez1, Nathaly Segovia-Ramos2, Víctor Ramos-Pérez2 and Salvador Borrós2
1
Biocolloid and Fluid Physics Group, Department of Applied Physics, University of Granada, 18071
Granada, Spain.
2
Group of Material Engineering GEMAT-IQS, University of Ramon Llull, 08017 Barcelona, Spain.
*
[email protected]
One of the approaches to deal with the development of non-viral gene carriers based
on DNA condensation by cationic polymers consists on analysing the forces involved in the
formation of the corresponding polyplexes. The long-range electrostatic attraction between the
negative phosphate groups of the DNA chain and many polycations is usually complemented
with short-range van der Waals attractions, and, in some cases, with hydrophobic forces
among non-polar moieties. To gain an insight into this aspect, in the present work we study
the effect of incorporating a small aliphatic chain to biodegradable linear poly(E-amino esters)
on compaction of a plasmid DNA. The physicochemical characterization of the formed
polyplexes has been carried out by means of dynamic light scattering (DLS), laser Doppler
electrophoresis, Nanoparticle Tracking Analysis (NTA) and agarose gel electrophoresis. Our
results suggest that the inclusion of a small hydrophobic fragment into the polycation
backbone may improve the overall properties of synthetic DNA carriers, in such a way that the
formed polyplexes became more positively charged at high polymer loads, the degradation by
hydrolysis was slowed down, they became more resistant to aggregate at high polymer
concentration loads, and a better protection of DNA strands was achieved. Although
nowadays many studies are mainly interested in the final transfection performance, studying
other basic aspects, as the role played by different forces during compaction, the interaction
potentials controlling the colloidal stability of the polyplexes or the degradation/desorption
kinetics in simple and simulated biological media, may help to improve the development of
future carriers.
Acknowledgements: The authors wish to express their appreciation for the financial support granted by
the following research projects: MAT2010-20370 - European FEDER support included - (MICINN,
Spain), P07-FQM3099 and P10-CTS-6270 (Junta de Andalucía, Spain), CEIBiotic 20F12/16. Azahara
Rata-Aguilar thanks the Government of Spain (MECD) for her FPU fellowship. GEMAT group would
like to thank Generalitat de Catalunya for its support through the Consolidated Grant 2009 SGR 1461.
[1] Wagner, E., Pharmaceutical Reseach 2004, 21, 8-14.
[2] Monserrat, M.; Garreta, E.; González, F.; Gutiérrez, J.; Eguizábal, C.; Ramos, V.; Borrós, S.; Izpisua
Belmonte, J.C., J. Biol. Chem. 2011, 286, 12417-12428.
[3] Estévez-Torres, A.; Baigl, D., Soft Matter 2011, 7, 6746-6756.
220
P76
Silicon colloids based applications to biosensing and sun resistant materials
I. Rodriguez1,2,*, R. Fenollosa1,2, and F. Meseguer 1,2
2
1
Unidad Asociada ICMM/CSIC-UPV, Universidad Politécnica de Valencia, 42022.
Instituto de Ciencia de Materiales de Madrid (CSIC), Cantoblanco, 28049 Madrid (Spain).
*
[email protected]
We have recently developed a new type of silicon structure that we name as Silicon
Colloids [1]. They are able to scatter light very efficiently in a large-span frequency range,
covering form the visible to the far infrared regions. Silicon colloids have unique properties
because:
A) They behave as optical microcavities with a high refractive index.
B) Their small size (from several hundred nanometers to few micrometers) and smooth round
surface open the possibility of developing powders and pigments, able to block the infrared
and thermal radiation coming from either the sun or from any other hot body.
C) As they are made of a semiconductor material they can be further processed for developing
electronic devices.
Here we report on the processing of silicon colloids as well as their applications to:
1. Nanomaterials for sensing [2,3]
2. IR protective coatings [4]
3. Sun resistant plastics and polymers [5]
[1] R. Fenollosa, F. Meseguer, and M. Tymczenko, Patent WO 2008155438
[2] F. Ramiro-Manzano, et al. Adv. Mater. 2011, 23, 3022
[3] I. Rodriguez et al., Submitted.
[4] I. Rodriguez, R. Fenollosa, A. Perez-Roldan and F. Meseguer, Patent WO 2011092368 and
Cosmetics&Toilettries, Sept. 2010.
[5] I. Rodriguez, R. Fenollosa, A. Perez-Roldan and F. Meseguer, Patent WO 2012101306
221
P77
Surface modification of lipid nanoparticles using poloxamer 407 surfactant.
Effects on cellular uptake
P. Sánchez-Moreno1, J. L. Ortega-Vinuesa1, J. A. Marchal-Corrales2, Anna Salvati3, K. A.
Dawson3, J. M. Peula-García4
1
2
Biocolloids and Fluids Physics Group, Dpt. of Applied Physics, University of Granada, Spain.
Human Anatomy and Embryology Department, University of Granada, 18071 Granada, Spain
3
Centre for BioNano Interactions,University College Dublin, Belfield, Dublin, Ireland.
4
Dpt. of Applied Physics II, University of Málaga, Spain.
*
[email protected]
A lot of studies indicate the importance of the nanoparticle-surface shell structure in cell
uptake pathways and denote the role of particle design in nanomedicine. In this work, we have
synthesized and physico-chemically characterized four different lipid-nanoparticles systems in which the
core was constituted by olive oil and the shell by phospholipids (lecithin), poloxamer 407 (Pluronic®
F127), and their combinations. The principal aim was to investigate the effect of the nanostructure
surface on the lipid-nanoparticle uptake process in a human lung adenocarcinoma epithelial cell line
(A549). The presence of hydrophilic polymers (poloxamers) in the surface enhances the intrinsic
colloidal stability of the system and it also influences their interaction with plasma proteins, which is a
process that may have an important impact on the in vivo long-term stability of the nanosystem [1] and
on the nanoparticle-cell interactions [2]. The uptake process was analyzed in vitro with flow cytometry
and cytotoxicity experiments using loaded nanoparticles with a fluorescent dye and a hydrophobic
cytotoxic drug respectively, being confirmed by confocal microscopy. The experimental results showed
an increase of the uptake amount increasing the phospholipid concentration in the nanoparticle shell. The
main reason for this result could be attributed to the structural similarities between the phospholipidic
coating of the nanoparticles and the cell membrane.
Figure caption: Relative fluorescent intensity of the A549 cell line when incubated with Nile-Red-loaded
nanocapsules for different times.
Acknowledgements: P. Sánchez-Moreno thanks to the European Science Foundation for their scolarship inside the
project: “Mapping the detailed composition of surface adsorbed protein layers on biomaterials and nanoparticles”.
The authors thank the financial support given by the projects MAT2010-20370 (European FEDER support included,
MICINN, Spain), and P07-FQM2496, P10-CTS-6270 and P07-FQM3099 (Junta de Andalucía, Spain).
[1] Sánchez-Moreno P., Ortega-Vinuesa J.L., Martín-Rodríguez A., Boulaiz H., Marchal-Corrales J.A. and PeulaGarcía, J.M., Int. J. Mol. Sci. 2012, 13, 2405-2424.
[2] Lynch I., Salvati A., Dawson K.A., Nature Nanotech. 2009, 4, 546-547.
222
P78
Rationale design of nanoemulsions for the delivery of hydrophobic bioactive
compounds: from surfactants and interfaces to in vivo results
Miguel Wulff-Pérez1, Antonio Martín-Rodríguez1, Juan de Vicente1, Antonia Serrano2,
Francisco Javier Pavón2, María J. Gálvez-Ruíz1,*
1
Biocolloid and Fluid Physics Group, Applied Physics Department, University of Granada, Fuentenueva
s/n, 18071,Granada, Spain
2
Fundación IMABIS, Hospital Carlos Haya de Málaga, Laboratorio de Medicina Regenerativa, Avenida
Carlos Haya 82, 29010, Málaga, Spain
*
[email protected]
Oil-in-water nanoemulsions (i.e. nano-sized droplets of oil dispersed in water)
present several advantages to be used as delivery systems for hydrophobic drugs: great
stability against creaming/sedimentation, large surface area, possibility of intravenous
administration, high biocompatibility, etc [1]. However, our knowledge of the relationship
between composition and final in vivo properties needs to be improved in order to design
rationally these nanoemulsions as carriers. In this work, nanoemulsions have been prepared
using natural oils and FDA-approved polymeric surfactants. The influence of the surfactant
properties on the interfacial behavior as well as on the macroscopic properties of the
nanoemulsions has been analyzed. In vitro tests have been also carried out to select the best in
vitro performance, by studying the impact of the surfactant structure on the biodegradation of
these nanoemulsions (lipolysis). Finally, the optimized nanoemulsions have been used to
administer oleoylethanolamide, a natural hydrophobic compound with anti-obesity properties.
Nanoemulsions containing oleoylethanolamide have been administered then to Wistar rats,
both orally and parenterally, and the effects of this formulation on the food intake have been
monitored. The in vivo results showed a good performance of the nanoemulsions as carriers of
hydrophobic compounds, confirming the properties predicted on a basis of a fundamental
science approach.
Acknowledgements: Authors thank the financial support given by the projects: P07-FQM03099 (Junta
de Andalucía), CEI-BioTic 20F12/16 y Micro proyecto CEI BioTic Granada, convocatoria 2013
(Campus de Excelencia Internacional BioTic Granada) y MAT2010-20370 (Ministerio de Educación y
Ciencia, España).
[1] Tadros, T.F.; Izquierdo, P.; Esquena, J.; Solans, C., Adv. Colloid Interface Sci. 2004, 108, 303–318.
AUTHOR INDEX
AUTHOR INDEX
A
Acosta, E.
Adboudzadeh, A.
Aguilella-Arzo, M.
Aguirre, G.
Ahijado-Guzmán, R.
Aicart, E.
Aicart-Ramos, C.
Alatorre-Meda, M.
Alejo, T.
Almeida, C. R. M.
Alsina, M. A.
Altantzi, T.
Álvarez, L. J.
Alvarez-Puebla, R.
Alves, C.
Alves, L.
Amaral, V. S.
Amigo, A.
Amirfazli, A.
Angelova, A.
Anta, J. A.
Antunes, F. E.
Araújo, J. P.
Araújo, M. J.
Arellano-Varela, J. E.
Arias-Estevez, M.
Arzac, A.
Astray, G.
Asua, J. M.
B
Baghdadli, N.
Bagherifam, S.
Bailey, A. E.
Bals, S.
Bar, I. P.
Barandiaran, M. J.
Barata, J. F. B.
Barbosa, S.
Barrán-Berdón, A. L.
Bastos-González, D.
Benavente, J.
Blanc, C.
Blanco, M. C.
Blasco-Avellaneda, D.
Blazevska-Gilev, J.
225
P60
P28
O6.5
P74
O7.1
PSS21
PSS21
O1.13, P19, P64
O5.7, P61
P24
PSS18, P62
CT2
P34
O1.4, P11
P40
PSS09, P23, P25,
P27
P18
P60, P70
P68
O6.5
I6, O6.3, O6.6
PSS09, P23, P25,
P27
P12
P37
P59
P49
P41
P67, P71
P09
P33
O1.11
O2.2
CT2, P14
O5.1
P28
P01
O1.13, P19, P29
PSS21, P72
I5, O5.6, P46,
P63
O5.3, P20
PL1
O4.2
P56, P68
P41
Blomberg, E.
Bonales, L. J.
Bordi, F.
Borrós, S.
Böttcher, A.
Braeckmans, K.
Brezesinski, G.
Buceta, D.
Burboa, G.
Burgos, J.
Busquets, M. A.
Burrows, H. D.
C
Cabrerizo-Vílchez, M. A.
Cajal, Y.
Calderó, G.
Callejas-Fernández, J.
Calvo, E.
Camacho, L.
Cambón, A.
Cano-Sarabia, M.
Capriotti, A. L.
Caracciolo, G.
Cardoso, A. M. S.
Cardoso, I.
Carnero-Ruiz, C.
Carregal-Romero, S.
Caruso, G.
Carvalho, H.
Carvalho, R. S.
Casals, E.
Cascante, M.
Castelletto, V.
Castelló, J.
Castro, R. A. E.
Castro-Hartmann, P.
Cavaleiro, J. A. S.
Cavaliere, C.
Cazeneuve, C.
Cerdà, J. J.
Chapel, J.-P.
Charas, A.
Chen, S.
Chmelka, B. F.
Chuliá, R.
Cid, A.
O2.3
O5.4
PSS14
P75
PSS09
O3.1
P65
O4.2
PSS19, P64
P69
PSS01, P03, P62
O1.12, O2.4,
PSS08, P26
O5.2, O5.5,
PSS02, PSS16,
P56, P59, P66,
P68
P58
O3.3, PSS07
O6.3, P42, P46
P60
P65
O1.13, P19, P29
O6.5
P72
P72
O7.4, P40
P73
P30, P36
O1.1, O1.7, P19
P72
PSS23
P43
O1.13
P51
P29
P03
O1.12
PSS21
P01
P72
P33
CT3
O5.6
I7
PSS02
CT2
O5.4
P50, P71
AUTHOR INDEX
Claesson, P.
Clara-Rahola, J.
Colomer, A.
Contreras-Cáceres, R.
Coronado-Puchau, M.
Costa, C.
Costa, T.
Creaney, B.
Cruz-González, S.
Cuetos, A.
D
Damas, L.
Daniel-da-Silva, A. L.
226
O2.3
P48
P44
P48
O1.14
P25, P27, P45
O2.4, PSS08
O1.5
O1.10
O6.1, O6.6
Drummond, C.
Duarte, C. M. G.
P02
O1.5, P01, P12,
P18, P43
O1.6
O1.10
P54
P77
PSS08
O4.1, PSS20,
P21, P78
O1.12
P52
I3, PSS10
P62
CT2
O3.5, O7.4,
PSS15, P40, P45
I5, O5.6, P63
PSS09
E
Edgar, J.
Elaissari, A.
Escribano, B.
Escribano, E.
Espinosa, G.
Espuny, M. J.
Esquena, J.
Estelrich, J.
O7.1
CT1, P06
CT7
PSS01
O2.2
P44
O2.3, PSS07
PSS01, P03, P04
F
Fajgar, R.
Fanun, M.
Faraudo, J.
Fateixa, S.
Féliz, D.
Fenollosa, R.
Fernandes, A. M.
P41
PSS11
I5, O6.5
O1.3
O3.5
O1.2, P76
P28
Dashtimoghadam, E.
David, C.
Daviña, R.
Dawson, K. A.
de Azebedo, D.
de Vicente, J.
de Zea Bermudez, V.
Delgado, A. V.
Dias, R. S.
Domènech, O.
Donaldson Jr, S. H.
do Vale, M. L. C.
Fernandes, R.
O5.1
Fernández-Barbero
O3.6, P39, P48
Fernandez-Nieves, A.
PL1, P55
Fernández-Piñas, F.
P13
Fernandez-Rodriguez, M. A. PSS02, P66
Fernandez-Rubio, J. E.
O5.4, O5.8
Ferrer-Tasies, L.
O6.5
Fessi, H.
CT1
Fey, A.
O1.4, P11
Figueira-González, M.
O2.6
Fijten, M.
I8
Firmino, T.
O6.4
Fischer, V.
O1.14
Fonseca, S. M.
O2.4, P26
Forcada, J.
P42, P74
Francisco, V.
O2.6, P45,
Frisken, E. J.
O2.2
Furó, I.
O5.1
G
Galceran, J.
Galera-Cortés, E.
Gallardo, M. A.
Gálvez-Ruíz, M. J.
Garcés, J. L.
García, J.
García de Abajo, F. J.
García-Calvo, E.
García-Jara, L.
García-Río, L.
Giner-Casares, J. J.
Girona, V.
Gomes, A. C.
Gonçalves, O.
González, N.
González, V. D. G.
González-Pérez, A.
Gonzalo, S.
Goris, B.
Goy, S.
Graça, M.
Gracia, R.
Gracia-Fabrique, J.
Grau-Campistany, A.
Griffiths, G. W.
Grzelczak, M.
Gudiña, E. J.
O1.10
P04
PSS01, P03
P78
P51
O5.3
O1.4
P13
PSS22
O2.6, P45
P57, P65
PSS18, P62
O3.1, O7.2,
PSS23
PSS23
O1.13, P29
P46
P29
P13
CT2
O1.13
P01
P28
P60, P70
P58
O1.11
CT2, O1.8,
O1.14, P08, P14,
P16
I1
AUTHOR INDEX
Guerrero-Barba, F.
Guerrero-Martínez, A.
H
Haake, H.-M.
Haba, E.
Hamley, I.
Hasirci, N.
Hasirci, V.
Hellweg, T
Henkel, A.
Hernández, A.
Hernando, B.
Herrera-Márquez, O.
Heuts, H.
Hidalgo-Álvarez, R.
227
P59
CT6
Hierrezuelo, J.
Hierrezuelo, J. M.
Holgado-Terriza, J. A.
Holm, C.
Homs, M.
Hühn, D.
PSS09
P47
P29
O1.11
O1.11
CT5
O7.1
PSS24
O5.3
P05
I8
O4.1, PSS02,
PSS20, P04, P21
P20
P30, P36
O5.2
CT3
O3.3
O1.7
I
Iglesias-Otero, M. A.
Imaz, A.
Infante, M. R.
Israelachvili, J. N.
P50, P67
P42, P74
O3.2, PSS13, P44
CT2
J
Jimenez, G.
Jimenez de Aberasturi, D.
Jimenez-Millán, E.
Jódar-Reyes, A. B.
Jorge, A. F.
Juárez, J.
Juárez-Ramírez, I.
Junquera, E.
Jurado, A. S.
Jurado, E.
PSS22
O1.7
P65
P75
PSS10
PSS19, P64
PSS06
PSS21
O7.4, P40
P05
K
Kaewsaneha, C.
Khorshid, N.
Klotz, B.
Knaapila, M.
Knudsen, K.
Kraft, M.
P06
P31
PSS09
PSS08, P26
P31
PSS08
L
La Porta, A.
Ladj, R.
Laganà, A.
Landfester, K.
Langer, J.
Le-Dantec, R.
Leganés, F.
Leiza, J. R.
Lesieur, S.
Leyva-Porras, C. C.
Lima, M. C. P.
Lindman, B.
Llamas, S.
Lopes, C. B.
Lopes, D.
Lopez-Cabarcos, E.
López-Cervantes, J. L.
López-León, T.
López-Quintela, M. A.
López-Romero, J. M.
Luckam, P.
Luengo, G.
Lund, R.
Luque-Caballero, G.
P08
CT1
P72
O1.14
P07
CT1
P13
P09
O6.5
PSS06
O7.4, P40
O3.2, PSS09,
P25, P27
O2.3
CT2, CT6, O1.4,
O1.8, O1.14,
PSS02, PSS04,
PSS05, PSS17,
P07, P08, P14,
P15, P16, P17,
P57
P33
P12, P18
PSS03
P32
P60, P70
PL1
O4.2
P20
P38
P33
O2.1
O7.3
M
Madurga, S.
Maestre, A.
Maestro, A.
Mælandsmo, G. M.
Maldonado-Valderrama, J.
Maldonado-Valdivia, A.
Mancebo, N.
Manresa, M. A.
Manso, J. A.
Marchal-Corrales, J. A.
Maroto-Centeno
Marques, A. T.
P51
O2.7, P35
O5.4
O1.11
O5.2, O7.3
O3.6, P39, P48
O5.4
PSS13, P44, P47
PSS12, P49, P50
PSS22, P77
O6.2
O2.4
Liu, C.
Liz-Marzán, L. M.
AUTHOR INDEX
Marques, E. F.
Martens, T.
Martín, V. I.
Martín-García, B.
Martín-Molina, A.
Martín-Rodríguez, A.
Martín-Romero, M. T.
Martínez-Pedrero, F.
Mas, F.
Mecerreyes, D.
Medronho, B.
Mehravar, E.
Mejuto, J. C.
Mendoza, A. J.
Merchán, M. D.
Meseguer, F.
Mezei, A.
Mezerji, H. H.
Miguel, M. G.
Miraballes-Martínez, I.
Miras, J.
Mirzadeh, H.
Mitjans, M.
Moldes, O. A.
Molina, R.
Molina-Bolívar, J. A.
Moncho-Jordá, A.
Monteiro, O. C.
Montenegro-Martos, J. M.
Moraila-Martínez, C. L.
Morais, C. M.
Morales, J.
Morales, M. P.
Morales-Sánchez, A.
Morán, M. C.
Moreno, M.
Moreno-Calvo, E.
Morros, J.
Mosquera, V.
Mounier, Y.
Moyá, M. L.
Muñoz, J.
Muñoz, M.
Muñoz-Bonilla, A.
Muñoz-Espí, R.
228
O2.6, O3.5, O5.1,
O7.4, PSS15,
P37, P40, P45
O3.1
O2.7, P34, P35
O1.9
O6.2, O7.3,
PSS21, P73
PSS22, P75, P78
P65
O5.4, O5.8
O1.10, P51
P28
P25, P27
P09
PSS12, P49, P50,
P67, P71
O5.4
O5.7, P61
O1.2, P76
O2.5
P14
O3.2, P27
PSS24
O2.3
O1.6
PSS13
PSS12, P67, P71
PSS07
P36
O6.3, P42
P10
O1.7
O5.5, PSS16
O7.4
PSS12, P49, P50
P21
P22
O2.5, PSS10
P28
O6.5
O3.2
O1.13, PSS19,
P19, P29, P64
CT1
O2.7, P34, P35
P53
P62
I8
O1.14
Muñoz-Juncosa, M.
Muñoz-Úbeda, M.
PSS18
PSS21
N
Naous, M.
Nascimento, B. F. O.
Neiser, A.
Neves, M. C.
Neves, P. M. S.
Nielsch, K.
Nieto-Ortega, B.
Nobili, M.
Noguera-Marín, D.
Novikov, S. M.
Nunes, M. R.
Nunes, S. C. C.
Nyström, B.
P36
P24
O7.1
PSS03, P10
P01
O5.3
P30
PL1
PSS16
PSS17
P10
O6.4
O1.6, O1.11, P31
O
Oliveira, A. C. N.
Oliveira, I. S.
Oliveira, M. E. C. D. R.
Ortega, F.
Ortega-Vinuesa, J. L.
Ortiz, A.
Ott, A.
P
Pagonabarraga, I.
Pais, A. A. C. C.
Paiva, D.
Palchetti, S.
Parajó, M.
Parak, W. J.
Pastor, I.
Pastoriza-Santos, I.
Patti, A.
Pavlov, V.
Pavón, F. J.
Pazos-Perez, N.
Pemartin, K.
Perea, R.
Pereira, E.
Pereira, M. d. C.
Pereira, R. F. P.
Pérez, L.
Pérez, L.
O3.1, O7.2
PSS15, P37
O3.1, O7.2,
PSS23
O3.4, O5.4, O5.8,
P33
P75, P77
PSS18, P62
O1.1
CT4
O6.4, PSS10,
P02, P23
P73
P72
O2.6
O1.1, O1.7, P19
P51
PSS05
O6.1, P69
O1.14
P78
O1.4, P11
PSS06, P22
P38, P52
P12, P18
P73
O1.12, P24
PSS13
PSS21, P44, P47
AUTHOR INDEX
Pérez-Fuentes, L.
Pérez-García, S. A.
Pérez-Juste, J.
Pérez-Mosqueda, L. M.
Perlich, J.
Persson, K.
Peula-García, J. M.
Pikabea, A.
Pinazo, A.
Pinedo, R.
Pinheiro, P. C.
Piñeiro, M.
Plaza, A.
Polavarapu, L.
Polpanich, D.
Pons, R.
Pozzi, D.
Pradhan, S.
Pragana, J.
Prasad, J.
Prat, J.
Prida, V. M.
Prieto, G.
Puertas, A. M.
Pujol, M.
Puntes, V. F.
Puy, J.
229
I5, P63
PSS06
CT2, PSS05, P14
P53
P26
O2.3
PSS22, P77
P74
PSS13, P44, P47
O1.7
P12
P02, P24
P05
PSS04
P06
O2.5, O3.2,
PSS17, P44, P47
P72
P26
O2.4
O7.1
PSS18, P62
O5.3
PSS14, P54
I4, O6.6
PSS18, P58, P62
O1.13
O1.10
Q
Queralt, J.
Quesada-Pérez, M.
Quindant, R.
PSS01
O6.2, P42, P73
I10
R
Rabanal, F.
Raemdonck, K.
Ramadan, Y.
Ramírez, P.
Ramos, J.
Ramos-Pérez, V.
Ramos-Tejada, M. M.
Rata-Aguilar, A.
Regev, O.
Rey-Castro, C.
Ricart, S.
Riccioli, A.
Richter, R. P.
Rivas, J.
Robles, E.
P58
O3.1
P32
P53
P42, P74
P75
P38, P52
P75
O5.1
O1.10
O6.5
P72
I1
O4.2
P64
Rocha, J.
Rocha, S.
Rodea-Palomares, I.
Rodrigues, L. R.
Rodríguez, A.
Rodríguez, I.
Rodríguez-Abreu, C.
Rodríguez-Dafonte, P.
Rodríguez-Fernández, D.
Rodríguez-González, B.
Rodríguez-Valverde, M. A.
Rojo, T.
Romero, V.
Rosal, R.
Rosman, C.
Ruano, M.
Rubia-Payá, C.
Rubio, R. G.
Rubio-Retama, J.
Rudzka, K.
Ruiz, E. D.
Ruiz de Larramendi, I.
Ruiz-López, J. A.
S
Saa, L.
Sabín, J.
Salgueiro, A. M.
Salvador, J.
Salvati, A.
Sanchez, C.
Sánchez, P. A.
Sánchez-Domínguez, M.
Sánchez-Iglesias, A.
Sánchez-Moreno, P.
Sánchez-Treviño, A. Y.
Sande, S. A.
Sandoval-Ibarra, F. D.
Sangrà, M.
Sanz-Ortiz, M. N.
Sarmiento, F.
Scarabelli, L.
Scherf, U.
Segovia-Gutiérrez, J. P.
Segovia-Ramos, N.
Serrano, A.
P18
P73
P13
I2
O2.7, P35
P76
P55
O2.6
PSS05
P21
O5.5, PSS02,
PSS16, P56, P59,
P66, P68
O1.7
O5.3
P13
O7.1
O3.4
P65
O3.4, O5.4, O5.8,
P33
P32
P52
PSS19
O1.7
PSS20
O1.14
O2.2, PSS14
O1.5
O1.10
P77
PL2
CT3
PSS06, P22
CT2, PSS02, P07,
P08, P14
P77
P56, P66
P31
P70
PSS01
P15
PSS14, P54
O1.8
O2.4, PSS08, P26
O4.1
P75
P78
AUTHOR INDEX
Serrano-Montes, A. B.
Shi, L.
Shiohara, A.
Shtein, M.
Sierra-Martín, B.
Silva, J. P. N.
Silva, M. M.
Silva, N. J. O.
Silva, S. G.
Silvestre, A. J.
Sintes, T.
Siretanu, I.
Solans, C.
Solier, J. D.
Song, Y.
Sönnichsen, C.
Sóñora, C.
Sousa, C. T.
Sousa, J. J.
Spasevska, D.
Stewart, B.
T
Taboada, P.
Tangboriboonrat, P.
Taromi, F. A.
Tavano, L.
Tavares, D. S.
Tebbe, M.
Teixeira, J. A.
Thormann, E.
Tirado-Miranda, M.
Toimil, P.
Tomovska, R.
Topete, A.
Torcello-Gómez, A.
Torkkeli, M.
Trindade, T.
Tyrode, E.
V
Valdes, M. A.
Valente, A. J. M.
Van Herk, A.
230
P16
O1.2
P07, P17
O5.1
O3.6, P39, P48
O7.2, PSS23
PSS03
P18
O3.5, O7.4,
PSS15, P40
P10
CT3
O5.6
O3.3, PSS06,
P22, P55, P69
P04
PSS02
O7.1
PSS24
P12
P02, P23
P41
O2.4, P26
I9, O1.13, PSS19,
P19, P29, P64
P06
O1.6
PSS13
P12, P18, P43
P11
I2
O2.3
P46
P54
P41
O1.13, P19, P29
O5.2
P26
PL3, O1.3, O1.5,
PSS03, P01, P12,
P18, P43
O2.3
PSS19, P64
O1.12, PSS08,
P24
I8
Van Tendeloo, G.
Varol, H. S.
Vazquez, M. I.
Vázquez-Vázquez, C.
Veciana, J.
Vega, V.
Vela-Gonzalez, A. V.
Velázquez, M. M.
Ventosa, N.
Vereda, F.
Vicaria, J. M.
Vidal-Lopez, G.
Vilanova, N.
Vilar, E
Vilar-Vidal, N.
Vilaseca, E.
Vílchez, S.
Vílchez-Maldonado, S.
Villar-Alvarez, E.
Vinardell, M. P.
Vitorino, C.
CT2
O1.14
P20
PSS14
O6.5
O5.3
PSS06
O1.9, O5.7, P61
O6.5
P21
P05
P22
P55
P19
O4.2
P51
O2.3
PSS07
O1.13, P29
PSS10, PSS13
P02, P23
W
Wagner, C. S.
Wedel, B.
Wittemann, A.
Wulff-Pérez, M.
O1.4
CT5
O1.4
P78
Z
Zeiser, M.
Zierold, R.
CT5
O5.3
ISBN 978-84-9860-832-8

5th Iberian Meeting on Colloids and Interfaces, RICI5

Transcription

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