title: Determination of the enantiomers of omeprazole in blood plasma by normal-phase liquid chromatography and detection by atmospheric pressure ionization tandem mass spectrometry.
abstract: An enantioselective assay of omeprazole in blood plasma using normal-phase liquid chromatography on a Chiralpak AD column and detection by mass spectrometry is described. Omeprazole is extracted by a mixture of dichloromethane and hexane and, after evaporation, redissolution and injection, separated into its enantiomers on the chiral stationary phase. Detection is made by a triple quadrupole mass spectrometer, using deuterated analogues as internal standards. The method enables determination in plasma down to 10 nmol/l (LOQ) and shows excellent consistency suited for pharmacokinetic studies in man.
authors.affiliation: Bioanalytical Chemistry, AstraZeneca R&D Mölndal, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Stenhoff
authors.forename: A
authors.initials: A
authors.lastname: Blomqvist
authors.forename: P O
authors.initials: PO
authors.lastname: Lagerström
mesh_terms: D000897:Anti-Ulcer Agents / Q000097:blood*; D002853:Chromatography, Liquid; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D009853:Omeprazole / Q000097:blood* / Q000737:chemistry; D011786:Quality Control; D012680:Sensitivity and Specificity; D013237:Stereoisomerism
chemical_list: D000897:Anti-Ulcer Agents; D009853:Omeprazole