title: Development of a LC-MS/MS method for the estimation of clinofibrate in human urine.
abstract: A highly sensitive and rapid liquid chromatography-tandem mass spectrometry method was developed for the determination of clinofibrate in human urine. The analyte and IS were extracted through a simple protein precipitation by the mixture of acetonitrile and 1 mol/L hydrochloric acid (95:5, v/v) and separated on an Inspire C18 (150 mm x 4.6 mm I.D., 5 μm particle size) column using isocratic elution with methanol and water containing 0.1% formic acid and 10 mM ammonium acetate (90:10, v/v). Mass spectrometric detection was performed in electrospray positive ionization MRM mode. The mass transition was m/z 486.3-->175.0 for clinofibrate and m/z 361.1-->233.1 for IS, respectively. The flow rate was 0.6 mL/min and the column oven temperature was set at 35 °C. The total run time was 6.5 min. Good linear relationships were obtained for all analytes over the concentrations ranging of 0.1002-10.02 μg/mL (r2 = 0.9991) and the limit of quantification was 0.1002 μg/mL. The extraction recovery was larger than 87.4% and intra- and inter-batch precision and accuracy with RSD were all less than 6.5%. The total amount of unchanged clinofibrate excreted in urine was less than 0.34%. This method was successfully applied to the pharmacokinetic study of clinofibrate in human urine.
authors.forename: Jian-Kang
authors.initials: JK
authors.lastname: Li
authors.forename: Chentao
authors.initials: C
authors.lastname: Lu
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Fan
authors.initials: F
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: Ge
authors.forename: Song
authors.initials: S
authors.lastname: Wei
authors.forename: Li
authors.initials: L
authors.lastname: Xueqing
authors.forename: Likun
authors.initials: L
authors.lastname: Ding
authors.forename: Wen
authors.initials: W
authors.lastname: Ai-Dong
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid; D005260:Female; D011345:Fenofibrate / Q000493:pharmacokinetics / Q000652:urine; D006801:Humans; D000960:Hypolipidemic Agents / Q000493:pharmacokinetics / Q000652:urine*; D008297:Male; D010642:Phenoxyacetates / Q000493:pharmacokinetics / Q000652:urine*; D012015:Reference Standards; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D000960:Hypolipidemic Agents; D010642:Phenoxyacetates; C006231:clinofibrate; D011345:Fenofibrate