A rapid and sensitive method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the determination of a novel anticoagulant peptide bivalirudin in human plasma has been developed and validated. Plasma samples were precipitated protein with acetonitrile and re-extracted with dichloromethane, after which the analyte and triptorelin as an internal standard (IS) were separated on a 300SB-C18 column (150 mm 4.6 mm i.d., 5 mm particle size) using 0.1% formic acid:methanol (45:55, v/v) as mobile phase. The triple-quadrupole mass spectrometer, equipped with electrospray ionization (ESI) interface, was operated in the positive ion mode, and the multiple-reaction monitoring (MRM) transitions of bivalirudin and IS were at m/z 1091.0-650.4 and m/z656.5-249.3, respectively. The lower limit of quantification (LLOQ) was 1 ng/mL for 100 mL plasma sample and the assay was linear over the concentration range 1-1000 ng/mL. The accuracy was within a range from 0.4% to 0.5% in terms of relative error (RE) and the intra- and inter-day precisions in terms of relative standard deviation (RSD) were r2.92 and r3.36, respectively. The method was successfully applied to a pharmacokinetic study involving intravenous administration of bivalirudin (0.5 mg/kg) to Chinese volunteers.
A rapid and sensitive method based on liquid chromatographtandem mass spectrometry (LC-MS/MS) for the determination of a novel anticoagulant peptide bivalirudin in human plasma has been developed and validated. Plasma samples were precipitated protein with acetonitrile and reextracted with dichloromethane, after which the analyte and triptorelin as an internal standard (IS) were separated on a 300SB-Cl8 column (150 mm x 4.6 mm i.d., 5 gm particle size) using 0.1% formic acid:methanol (45:55, v/v) as mobile phase. The triple-quadrupole mass spectrometer, equipped with electrospray ionization (ESI) interface, was operated in the positive ion mode, and the multiplereaction monitoring (MRM) transitions of bivalirudin and IS were at m/z 1091.0-650.4 and m/z656.5 - 249.3, respectively. The lower limit of quantification (LLOQ) was 1 ng/mL for 100 ng/mL plasma sample and the assay was linear over the concentration range 1 1000 ng/mL. The accuracy was within a range from -0.4% to 0.5% in terms of relative error (RE) and the intra- and inter-day precisions in terms of relative standard deviation (RSD) were 〈2.92 and 〈 3.36, respectively. The method was successfully applied to a pharmacokinetic study involving intravenous administration of bivalirudin (0.5 mg/kg) to Chinese volunteers.