title: On-line extraction coupled with liquid chromatography tandem mass spectrometry for quantitation of pravastatin and its metabolite in human serum.
abstract: A high-throughput bioanalytical method for simultaneous quantitation of pravastatin and its metabolite (M1) in human serum was developed and validated using on-line extraction following liquid chromatography tandem mass spectrometry (LC-MS/MS). The on-line extraction was accomplished by the direct injection of a 50 microL serum sample, mixed 4:1 with an aqueous internal standard solution, into one of the extraction columns with aqueous 1 mm formic acid at flow rate of 3 mL/min. The separation and analysis were achieved by back-eluting the analytes from the extraction column and the analytical column to the mass spectrometer with an isocratic mobile phase consisting of 62% aqueous 1 mm formic acid and 38% acetonitrile at a flow rate of 0.8 mL/min. The second extraction column was being equilibrated while the first column was being used for analysis, and vice versa. The standard curve range was 0.500-100 ng/mL for pravastatin and M1. The lower limit of quantitation, 0.500 ng/mL for all the analytes, was achieved when 50 microL of human serum was used. The intra- and inter-day precisions were within 7.4%, and the accuracy was between 95 and 103%. The on-line extraction was finished in 0.5 min and total analysis time was 2.5 min per sample.
authors.affiliation: Shandong Provincial Analysis and Test Center, Jinan, Shandong 250014, People's Republic of China. csywk@keylab.net
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Wang
authors.forename: Yongcheng
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000924:Anticholesteremic Agents / Q000097:blood* / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D007536:Isomerism; D016014:Linear Models; D017035:Pravastatin / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000924:Anticholesteremic Agents; D017035:Pravastatin