Comparing GCxGC-FID and GC-MS for Purity Checks of

Comparing GCxGC-FID and GC-MS for Purity Checks of

Comparing GCxGC-FID and GC-MS
for Purity Checks of Fragrance
Allergen Reference Materials
Jack Cochran, Julie Kowalski, Frank Dorman,
Scott Grossman, Gary Stidsen, and Jaap de Zeeuw
Restek Corporation, Bellefonte, Pennsylvania, USA
7th Amendment of the
European Cosmetics Directive
„
Certain substances are contact allergens for
fragrance-sensitive people
26 substances
„ 24 can be gas chromatographed
„
„
Allergens must be in product list of ingredients
if they exceed certain levels
0.001% in leave-on products
„ 0.01% in rinse-off products
„
Allergen Name
Amyl cinnamal
Benzyl alcohol
Cinnamyl alcohol
Allergen Name
Lyral
Anise alcohol
Benzyl cinnamate
Citral
Hydroxycitronellal
Eugenol
Farnesol
Lilial
Linalool
Isoeugenol
Amylcinnamyl alcohol
Benzyl salicylate
Benzyl benzoate
Citronellol
Hexyl cinnamal
Cinnamal
Coumarin
Geraniol
Limonene
Methyl 2-octynoate
Alpha-isomethyl ionone
Need for Fragrance Allergen
Analytical Reference Materials
„
Calibration and quantification for products
containing fragrances
Individuals available
„ But commercial mixes are wanted/needed
„
„
Quality assurance purposes
“Second source” standards
„ Regulating/auditing bodies may not want in-house
analysts preparing their own standards
„
Challenges for Fragrance Allergen
Analytical Reference Materials
„
„
Hard to find materials meeting purity
requirements
Vendor specified purities often in error
„
„
Even when they claim GC or GC-MS on certificate
of analysis!
Comprehensive mixes are unstable
Aldehydes and ketones together acceptable
„ Non-carbonyl compounds in separate mix
„
IFRA Allergen Standard
Purity Requirements
„
„
„
„
Almost all compounds: >95%
Alpha-isomethyl ionone: >88%
Isomers might be summed for purity
calculations
Method not clear as to how purity is determined
Presumed to be area% for this work
„ Does not necessarily specify GC-MS
„
GC-MS Conditions
„
„
Split injection (~20 mg/mL standards)
30m x 0.25mm x 0.25µm Rxi-5ms
Constant linear velocity helium, 35 cm/sec
„ 50°C (2 min), 10°C/min to 300°C (5 min)
„
„
Quadrupole mass spectrometer
Electron ionization at 70 eV
„ 40 to 400 m/z
„
GCxGC-FID
„
30m x 0.25mm x 0.25µm Rxi-1ms
„
100% dimethyl polysiloxane
„
40°C (1min), 4°C/min to 240°C
„
Thermal modulation, 3 sec
„
1m x 0.10mm x 0.10µm Rxi-17
„
„
50% diphenyl / 50% dimethyl polysiloxane
45°C (1min), 4°C/min to 245°C
GCxGC of Fragrance Allergens
Benzyl cinnamate
Benzyl benzoate
Anise alcohol
12
38
18
Benzyl alcohol
4
2
29
20
17
7
24
11
9
5
6
32
26
14
8
Lyral
Hexyl cinnamal
28
19
13 16
Citronellol
31
23
25
27
37
33 Farnesol
Limonene
Coumarin
<< Retention time (sec) Rxi-1ms >>
<< Retention time (sec) Rxi-17 >>
21
Amyl cinnamal
<< Rxi-17 >>
Lyral 1
Lyral 2
<< Rxi-1ms >>
Lyral
Allergen Name
Amyl cinnamal
Benzyl alcohol
Cinnamyl alcohol
Citral
Hydroxycitronellal
Eugenol
Isoeugenol
Amylcinnamyl alcohol
Benzyl salicylate
Cinnamal
Coumarin
Geraniol
GCxGC-FID
98.2
100
98.5
93.0
41.2
100
98.8
68.9
99.8
85.0
100
96.8
GC-MS
97.1
100
98.8
98.4
92.3
99.5
98.4
74.3
100
87.5
99.9
97.0
Allergen Name
GCxGC-FID
Lyral
98.5
Anise alcohol
99.7
Benzyl cinnamate
99.9
Farnesol
95.7
Lilial
94.1
Linalool
97.5
Benzyl benzoate
99.8
Citronellol
96.4
Hexyl cinnamal
95.7
Limonene
99.7
Methyl 2-octynoate
99.2
Alpha-isomethyl ionone
59.2
GC-MS
98.0
99.4
99.7
95.1
96.4
97.5
100
97.5
94.4
100
99.1
58.1
4.00
14.25
14.50
14.75
15.00
15.25
15.50
15.75
16.00
16.125
15.966
15.815
15.399
15.114
14.998
14.945
14.662
14.536
14.457
14.842
15.046
14.372
14.276
14.215
14.090
15.250
14.783
Alpha-isomethyl ionone
GCxGC-FID
GC-MS
16.25
RT (min)
14.09
14.22
14.28
14.37
14.46
14.54
Area%
7.3
0.39
0.24
1.7
0.78
0.43
14.66
0.49
14.78
14.84
58
3.7
RT1 (sec)
1587
1602
RT2 (sec)
1.60
1.65
Area%
7.2
0.052
1626
1638
1650
1668
1668
1680
1686
1695
1695
1.65
1.53
1.50
1.53
1.64
1.64
1.54
1.55
1.69
0.86
0.40
0.28
0.10
0.31
0.18
0.20
59
0.94
RT (min)
14.09
14.22
14.28
14.37
14.46
14.54
Area%
7.3
0.39
0.24
1.7
0.78
0.43
14.66
0.49
14.78
14.84
58
3.7
RT1 (sec)
1587
1602
RT2 (sec)
1.60
1.65
Area%
7.2
0.052
1626
1638
1650
1668
1668
1680
1686
1695
1695
1.65
1.53
1.50
1.53
1.64
1.64
1.54
1.55
1.69
0.86
0.40
0.28
0.10
0.31
0.18
0.20
59
0.94
4.00
14.25
14.50
14.75
15.00
15.25
15.50
15.75
16.00
16.125
15.966
15.046
14.842
14.783
15.250
58%
15.815
15.399
15.114
14.998
14.945
14.662
14.536
14.457
14.372
14.276
14.215
14.090
Alpha-isomethyl ionone
GCxGC-FID
0.94%
59%
GC-MS
3.7%
16.25
GCxGC-FID Repeatability
„
Alpha-isomethyl ionone
„
„
Has wide range of area percents
Three vials analyzed
Autosampler injections, 0.2µL
„ Triplicate injections of each, back-to-back
„
„
All data processing done automatically through
GCxGC software
„
No manual review or integration adjustments
Alpha-isomethyl ionone
<
1m
i
x
<R
>
>
s
<<
Rx
i-1
7
>>
RT1 (sec)
1695
1761
RT2 (sec)
1.55
1.57
Area% Avg
59
23
RSD%
0.71
0.51
ng OC
11
4.2
1587
1860
1.59
1.63
7.2
1.6
0.45
0.64
1.3
0.29
1626
1695
1800
1668
1.64
1.69
1.55
1.53
0.94
0.90
0.11
0.11
3.4
0.57
3.3
41
0.17
0.17
0.020
0.020
1311
2040
1.54
1.97
0.098
0.081
4.1
27
0.018
0.015
GCxGC-FID Linearity
„
Benzyl alcohol
100% purity
„ 20.94 mg/mL stock
„
„
2.09 pg to 20.9 ng on column
„
„
Four orders-of-magnitude
Calibration curve
External standard
„ 1/conc weighting
„
Benzyl alcohol
2.09 pg to 20.9 ng
Benzyl alcohol
2.09 pg to 209 pg
Zoom of lower end of 2.09 pg to 20.9 ng curve
GCxGC-FID of Perfumes
True Star
*
Geranial (Citral)
*
Tommy Girl
Methyl 2-octynoate
Estragole
Methyl 2-octynoate
Tommy Girl
Estragole
Perfume Analysis - Lovely
Allergen
Linalool
Geraniol
Hydroxycitronellal
Alpha-isomethyl ionone
Lilial
Amyl cinnamal
Hexyl cinnamal
Benzyl benzoate
Benzyl salicylate
GCxGC-FID
0.71
0.76
0.53
0.017
8.5
8.0
0.85
0.017
8.3
Values in area%
GC-MS
0.84
3.0
0.63
ND
7.4
ND
0.66
0.020
6.6
Amyl cinnamal?
Amyl cinnamal?
Methyldihydrojasmonate
Perfume Analysis - Lovely
Allergen
Linalool
Geraniol
Hydroxycitronellal
Alpha-isomethyl ionone
Lilial
Amyl cinnamal
Hexyl cinnamal
Benzyl benzoate
Benzyl salicylate
Rxi-17
0.71
0.76
0.53
0.017
8.5
8.0
0.85
0.017
8.3
Values in area%
Stabilwax
1.1
0.73
0.54
0.0077
8.3
ND
0.81
0.020
8.4
GC-MS
0.84
3.0
0.63
ND
7.4
ND
0.66
0.020
6.6
<< Rxi-17 >>
True Star
<< Stabilwax >>
<< Rxi-1ms >>
<< Rxi-1ms >>
Amyl cinnamal
<< Rxi-17 >>
Lyral 2
Lyral 1
<< Rxi-1ms >>
Lyral 1
<< Stabilwax >>
Amyl cinnamal
Lyral 2
<< Rxi-1ms >>
GC x Parallel Dual-Column GC-FID
Rxi-17 and Stabilwax secondary columns
GC x Parallel Dual-Column GC-FID
„
„
„
Use Gerstel MACH
as primary column
Modulate on 0.10mm
uncoated fused silica
Y split to two FIDS
Rxi-17 and Stabilwax
„ Use Agilent oven as
secondary oven
„
Acknowledgments
„
LECO, for GCxGC-FID
„
You, for your comprehensive attention
„
The organizing committee for the opportunity
to speak