title: Sensitive method for the quantitative determination of gemfibrozil in dog plasma by liquid-liquid cartridge extraction and liquid chromatography-tandem mass spectrometry.
abstract: A sensitive LC-MS/MS assay for the quantitative determination of gemfibrozil in dog plasma has been developed and validated and is described in this work. The assay involved the extraction of the analyte from 0.5-ml aliquots of dog plasma using Chem Elut cartridges and methyl tert.-butyl ether (MTBE). Chromatography was performed on a Metasil Basic column (50 x 2 mm I.D., 3 microm) using a mobile phase that consisted of 70:30 acetonitrile-ammonium acetate (1 mM, pH 5.0) with a flow-rate of 0.2 ml min(-1). The method showed excellent reproducibility with an inter- and intra-assay precision of <8.9% (%RSD), as well as excellent accuracy with an inter- and intra-assay accuracy between 99 and 101%. This method has a lower limit of quantitation (LLOQ) of 1.0 ng ml(-1) with a linear calibration range from 1.0 to 250 ng ml(-1). This new assay offers higher sensitivity and a much shorter run time over earlier methods.
authors.affiliation: Department of Drug Metabolism, Merck Research Laboratories, WP75A-303, P.O. Box 4, West Point, PA 19486, USA. brad_roadcap@merck.com
authors.forename: Brad A
authors.initials: BA
authors.lastname: Roadcap
authors.forename: Don G
authors.initials: DG
authors.lastname: Musson
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Rogers
authors.forename: Jamie J
authors.initials: JJ
authors.lastname: Zhao
mesh_terms: D000818:Animals; D004285:Dogs; D015248:Gemfibrozil / Q000097:blood*; D000960:Hypolipidemic Agents / Q000097:blood*; D013058:Mass Spectrometry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000960:Hypolipidemic Agents; D015248:Gemfibrozil