Sterols from Lard 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:0.70 g lard in 10 ml 0.5 M KOH in ethanol. Relux for 20 min at 77 °C. Cool down then add 10 ml 0.22 mg/ml betulin (istd) and shake for 10 min. Let still for some time then collect the liquid phase in 20 ml screw cap vial. Pipette 3 ml aliquot and filter through a BD 10 ml syringe screw to a Phenex 30 mm 0.45 Teflon filter, and collect it in a 4 ml amber color screw cap vial. Set up Strata C 18-E (55 um, 70 A) on a manifold with a vacuum pump over 1/125 mm culture tube then condition with 5 ml methanol and 5 ml chloroform. Replaced culture tube with collected condittioning material and set up a clean one. Pipette 1 ml filtrate on/at the miniscus chloroform-C 18-E SPE adsorbent and elute sterols with 15 ml 5 % methanol in chloroform. Collect eluted sterols in the label and clean culture tube and concentrate to 1 ml with nitrogen. Transfer 200 ul aliquot to a 500 ul insert sample vial and dry it with nitrogen. Reconstitute with 100 ul pyridine and derivatize with 100 ul BSTFA:TMCS; 99:1. Warmp up at 70 °C for 20 min then inject.
Final Prep and Analysis: Initial Sample Unit: gram Inject: 0.5 µL on GC / Flame Ionization (FID) @ / (320 °C)


Name Spiked
Log P pKa % Rec %RSC (n=0)
1 Cholesterol
2 Betulin

Application Detail (App ID: 16514)

Part No:7HG-G010-11
Phase:5% Phenyl-Arylene 95% Dimethylpolysiloxane
Dimensions:30 meters x 0.25 mm x 0.25 µm
Oven Profile:225 °C to 330 °C @ 15 °C/min for 2 min.
Carrier Gas:Constant Flow Helium, 2.5 mL/min
Injection:Splitless :1 0.5 µL @ 320°C
Detection: Flame Ionization (FID) (320°C)
Note:Sample prep- Saponification, Solid Phase Extraction (SPE), and Derivatization.

Analyte Details

Analyte Detail not available