title: New internal standard for quantitative determination of oxyphytosterols by gas chromatography.
abstract: A study was conducted to develop a new internal standard for the quantitative determination of oxyphytosterols. Tests on 5-androsten-3beta,17beta-diol; 5alpha-androstan-3beta,17beta-diol; 5-pregnen-3beta,20alpha-diol; and 5alpha-pregnan-3beta,20beta-diol showed that these compounds were not fully adequate. However, the compound 3beta,22-dihydroxy-20-homo-5-pregnene, synthesized in 4 steps, resulted in a promising internal standard, with a molecule similar to hydroxysterols; retention time as trimethylsilyl in gas chromatography comprised between 5alpha-cholestane and 7alpha-hydroxycholesterol; clear mass spectrum in electronic impact mass spectrometry, with several intense ions suitable for selected ion monitoring-mass spectrometry. Further studies are necessary to observe the behavior of these compounds during the entire analytical procedure.
authors.affiliation: Unité de Nutrition Lipidique, Institut National de la Recherche Agronomique, 17 rue Sully, B P86510, 21065 Dijon Cedex, France. grandgi@dijon.inra.fr
authors.forename: André
authors.initials: A
authors.lastname: Grandgirard
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Cabaret
authors.forename: Lucy
authors.initials: L
authors.lastname: Martine
authors.forename: Olivier
authors.initials: O
authors.lastname: Berdeaux
mesh_terms: D002849:Chromatography, Gas; D010084:Oxidation-Reduction; D010840:Phytosterols / Q000032:analysis*; D012015:Reference Standards
chemical_list: D010840:Phytosterols