For permission to reproduce any portion of this application note, please contact Restek’s publications/graphics department by phone (ext. 2128) or FAX.
Restek Trademarks:
Cyclosplitter, Rtx, Stabilwax.
Product Listing
Stabilwax
®
Columns
ID
df (µm)
Stable to
50m
0.25mm 0.25
250°C 10626-105
1. cholesterol
2. brassicasterol
3. campesterol
4. stigmasterol
5.
β
-sitosterol
Figure2
TheRtx
®
-5 columnhas the thermal stability toprovide
elution and accurate quantitation of the phytosterols,
even up to 340°C.
Determination of Sterols inSerenoaRepens
(SawPalmetto or Sabel) byGC
This assay canbeused todetermine stigmasterol, campesterol,
brassicasterol, andß-sitosterol in sawpalmetto fruit, oil extract,
andblendedpowders.Determination is performedusingGC
after hydrolysis, saponification, andderivatization. Formore
specific informationon themethod itself and all procedures
involved, please refer tohttp://www.nutraceuticalinstitute.com/
methods/sterols.html
The sterols from sawpalmetto are shown inFigure 2, whichwas
obtainedbyusing aRestekRtx
®
-5 column and aHewlett
Packard5890Series IIGC equippedwith anFID and an
autosampler. TheRestekRtx
®
-5 column contains a5%diphenyl/
95%dimethyl polysiloxanephase, andhas the thermal stability
toprovide elution and accuratequantitationof thephytosterols,
evenup to340°C.
Special thanks toDr.MarkLange, Director, and to
KathrynBass,MarketingDirector, ofMVP for
allowingus to print thismaterial.Much of this text
has been directly downloaded from the INAwebsite.
60m, 0.25mm ID, 0.25µmRtx
®
-5 (cat.# 10226). 1µL splitless injection*.
Oven temp.:
200°C (hold 1min.) to 340°C@ 15°C/min. (hold 10min.);
Inj./FID temp.:
345°C/355°C.
*Split injectionmay be used. A split flow of 112mL/min. is suggested. However, split
injectionmay result inhigher variability of results.
Rtx
®
-5Columns
ID
df (µm)
Stable to
60m
0.25mm 0.25
360°C
10226
1
2
3
4
5
15
5
min.
10
Formore informationonRestek’s Stabilwax
®
andRtx
®
-5GC columns, please request our informative
FastFactsFlyers
(Lit. cat.#59316 forStabilwax
®
andLit. cat.#59310 forRtx
®
-5).
Inlet Sleeves forHPGCs
Description ID/OD/Length
ea.
5-pk.
25-pk.
2mmSplitless 2.0/6.5/78.5mm 20712 20713 20714
4mmSplitless 4.0/6.5/78.5mm 20772 20773 20774
Inlet Sleeves forShimadzuGCs
Description ID/OD/Length
ea.
5-pk.
25-pk.
99mmSplit
3.5/5.0/99mm 20860 20861 20862
Cyclosplitter
®
3.5/5.0/99mm 20870 20871 —
