Sterols from Margarine on ZB-MR1

Sample Preparation Details

Part No:8B-S001-JCH
Solid Phase Extraction (SPE) procedure:Note: The solvent volumes shown below are for a 1 g bed mass. The solvent volumes will need to be adjusted for a smaller or larger bed mass.
Load:Shake and reflux 0.72 g of margarine in 20 ml 0.5 M KOH in ethanol at 78 °C for 20 min. At room temperature add to sample prep 10 ml 0.22 mg/ml betulin (istd) in chloroform and shake for 5 min. When settle,
pH (2-5) 3 ml of liquid phase with 5 M HCl in ethanol dropwise to 2.8 then transfer and filter
to a BD 10 ml needles syringe screw to a Phenex 30 mm 0.45 um teflon filter,
and collect filtrate in a 4ml screw cap sample vial. Set up and condition a Strata C18-E (55 um, 70 A) sorbent onto a manifold, plugged to a vacuum pump, and sorbent cartridge pointing into a 1/125 mm culture tube, with 5 ml methanol and 5 ml chlorofrom. Replaced culture tube with a new and label accordingly,
then transfer 1 ml filtrate onto miniscuos chloroform-sorbent and elute sterols with 15 ml 5 % methanol in chloroform. Concentrate sterols to 1 ml by blowing nitrogen onto eluant then
transfer 200 ul into a 500 ul insert sample vial, dry with nitrogen, reconstitute with 100 ul pyridine, and derivatize with 100 ul BSTFA:TMCS; 99:1. Stir and warm at 70 °C for 20 min and inject.
Final Prep and Analysis: Initial Sample Weight / Unit: 0.70 grams Inject: 0.5 µL on GC / Flame Ionization (FID) @ / (300 °C)


Name Spiked
Log P pKa % Rec %RSC (n=0)
1 Campesterol
2 Stigmasterol
3 b-Sitosterol
4 Betulin

Application Detail (App ID: 16544)

Part No:7HG-G016-11
Phase:Proprietary Pesticides Phase
Dimensions:30 meters x 0.25 mm x 0.25 µm
Oven Profile:From 230 °C to 320 °C @ 15 °C/min and hold for 5 min.
Carrier Gas:Constant Flow Helium, 2.5 mL/min
Injection:Splitless :1 0.5 µL @ 300°C
Detection: Flame Ionization (FID) (300°C)
Note:Sample prep- Saponification, pH Adjustment, Solid Phase Extraction (SPE), Reconstituted, Derivatization.

Analyte Details

Analyte Detail not available