title: Determination of omeprazole in human plasma by liquid chromatography-electrospray quadrupole linear ion trap mass spectrometry.
abstract: An analytical method for the determination of omeprazole in human plasma has been developed based on liquid chromatography mass spectrometry. The analyte and internal standard sildenafil are extracted from plasma by liquid-liquid extraction using diethyl ether:dichloromethane (60:40, v/v) and separated by reversed phase high-performance liquid chromatography (HPLC) using acetonitrile:methanol:10 mM ammonium acetate (37.5:37.5:25, v/v/v) as mobile phase. Detection is carried out by multiple reaction monitoring on a Q TRAP LC/MS/MS system (Q TRAP). The method has a chromatographic run time of 3.5 min and is linear within the range 0.50-800 ng/mL. Intra- and inter-day precision expressed as relative standard deviation ranged from 0.4 to 8.5% and from 1.2 to 6.8%, respectively. Assay expressed as relative error was <5.7%. The method has been applied in a bioequivalence study of two capsule formulations of omeprazole.
authors.affiliation: Research Center for Drug Metabolism, Jilin University, Changchun 130023, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Yingwu
authors.initials: Y
authors.lastname: Wang
authors.forename: J Paul
authors.initials: JP
authors.lastname: Fawcett
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jingkai
authors.initials: J
authors.lastname: Gu
mesh_terms: D002138:Calibration; D002626:Chemistry, Pharmaceutical / Q000379:methods; D002845:Chromatography; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid / Q000379:methods*; D004345:Drug Industry / Q000379:methods; D004791:Enzyme Inhibitors / Q000032:analysis / Q000737:chemistry; D006801:Humans; D013058:Mass Spectrometry; D008956:Models, Chemical; D015233:Models, Statistical; D009853:Omeprazole / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics*; D010879:Piperazines / Q000494:pharmacology; D011687:Purines; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000068677:Sildenafil Citrate; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013450:Sulfones; D013696:Temperature; D013997:Time Factors
chemical_list: D004791:Enzyme Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate; D009853:Omeprazole