SyntheticMushroomAroma
GC
Stabilwax®
RaspberryFlavor
GC
Rt-
β
DEXsa™
FOODS, FLAVORS,
& FRAGRANCES
23
Flavors & Fragrances / Chiral Separations
Phone: 800-356-1688 or 814-353-1300
ChiralSeparations
Chiral chromatography is the separationof enantiomeric compounds,which aremirror images of eachother that arenot superim-
posable.Common liquid stationaryphasesused inGC typicallyarenot able to resolveenantiomericcompounds.However, theaddi-
tion of derivatized cyclodextrinmolecules to common stationary phasesmakes such separations possible. Restek’s five chiral capil-
lary columns incorporate various combinations of alkylated
β
-cyclodextrins into a cyanopropyl-dimethyl siloxane liquid stationary
phase.Theunique combinations of cyclodextrins allow analysis of awide range of enantiomeric compounds.
Chiral capillary chromatography is a relatively new technique for determining the enantiomeric ratios of volatile components in
essential oils. Enantiomeric ratios can be used for determining the authenticity of an essential oil or for characterizing regional dif-
ferences amongoils.The separationof enantiomeric compounds in flavor and fragrance samples canbeoptimized through column
selection.Eachof the fiveRestekchiral columnsoffersadifferent selectivity.The
Rt-
β
DEXsp™
column isoptimized formenthol anal-
ysis,while the
Rt-
β
DEXsa™
columnprovides thebest separation for 1-octen-3-ol, carvone, camphor, 1-phenylethanol,
β
-citronellol,
and rose oxides.
Rt-
β
DEXsm™
and
Rt-
β
DEXse™
columns,used in combination,provide thebest resolution for
cis
- and
trans
-linalool
oxides, linalool, and linalyl acetate.The
Rt-
β
DEXcst™
column is ideal for semivolatile chiral compounds, including the irone isomers
and
γ
- and
δ
-lactones.
GC_FF00143
1
2
3
4
5
6
7 8
9
10
11
12
13
14
15
16
17
18
19
20
min.
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
1. acetone
2. ethyl acetate
3. methylene chloride (solvent)
4. hexanal
5. amyl acetate
6. 1-butanol
7. 3-methyl-1-butanol
8. 1-pentanol
9. 3-octanone
10. 3-octanol
11. nonanal
12. 1-octen-3-ol
13. furfural
14. benzaldehyde
15. octyl alcohol
16. phenylacetaldehyde
17.
α
-terpineol
18. 2,4-nonadienal
19. 2,4-decadienal
20. benzyl alcohol
30m, 0.32mm ID, 1.0µm
Stabilwax
®
(cat.# 10654)
1.0µL split injection of a
syntheticmushroom aroma
Conc.:
10ng per
component
Oven temp.:
40°C to 220°C
@6°C/min.
Inj. & det. temp.: 260°C
Carrier gas:
hydrogen
Linear velocity: 40cm/sec.
FID sensitivity:
4 x 10
-11
AFS
Split ratio:
100:1
30m, 0.32mm ID, 0.25µmRt-
β
DEXsa (cat.# 13108)
Oven temp.:
60°C (hold 2min.) to 200°C@3°C/min.
Carrier gas:
helium; 60cm/sec. set@60°C
Det.:
MS@220°C.
min.
10
20
30
40
1 2
1. (R)-
α
-ionone
2. (S)-
α
-ionone
GC_FF00161
