Region

Applications

Sterols pH from Olive Oil on ZB-5MS

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 0.7 g of olive oil in 10 ml 0.5 M KOH in ethanol at 77 °C for 20 min. At room temperature add to sample prep 10 ml 0.22 mg/ml betulin (istd) in chloroform and shake for 10 min. In a 20 ml sample vial pH (2-) 3 ml liquid phase to 2.4 with 5 M HCl in ethanol dropwise,
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 accordingl,
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, dry with nitrogen, reconstitute with 100 ul pyridine, and derivatize with 100 ul BSTFA:TMCS; 99:1. Warm up to 70 °C for 20 min and inject.
Final Prep and Analysis: Initial Sample Weight / Unit: 0.70 grams Inject: 0.5 µL on GC / Mass Spectrometer (MS) @ 250-500 amu / (275 °C)

Analytes:

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

Application Detail (App ID: 16528)

Part No:7HG-G010-11
Phase:5% Phenyl-Arylene 95% Dimethylpolysiloxane
Dimensions:30 meters x 0.25 mm x 0.25 µm
Oven Profile:From 220 °C to 330 °C at a ramp of 25 °C/min and hold for 5 min.
Carrier Gas:Constant Flow Helium, 1.5 mL/min
Injection:Splitless :1 0.5 µL @ 275°C
Detection: Mass Spectrometer (MS) (275°C)

Analyte Details

Analyte Detail not available

1
Campesterol
search

2
Stigmasterol
search

3
b-Sitosterol
search

4
Betulin
search