title: Capillary column gas-liquid chromatographic resolution of oxidized cholesterol derivatives.
abstract: Fused-silica capillary columns were evaluated for the resolution of oxidized cholesterol derivatives. Thermal instability of diol derivatives, epimeric 7 alpha- and 7 beta-hydroxy, 4 beta-hydroxy, and 25-hydroxycholesterol, was observed during gas chromatography. After derivatization as trimethylsilyl ethers the foregoing diols, alpha-epoxide, cholestane-triol, 7-ketocholesterol, and cholesta-3,5-dien-7-one were completely resolved on a DB-1 column. Each oxidized sterol revealed excellent response linearity as the trimethylsilylated sterol, enabling reliable quantification. The identity of each derivatized sterol was confirmed by mass spectrometry.
mesh_terms: D002784:Cholesterol / Q000031:analogs & derivatives* / Q000032:analysis; D002849:Chromatography, Gas / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry; D010084:Oxidation-Reduction; D013261:Sterols / Q000032:analysis
chemical_list: D013261:Sterols; D002784:Cholesterol