Highly sensitive and rapid ultra-performance liquid chromatography-tandem mass spectrometry method for the determination of nifedipine in human plasma and its application to a bioequivalence study

摘要

An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed for the determination of nifedipine in human plasma using nifedipine-d6 as the internal standard (IS). The plasma samples were prepared by solid-phase extraction on Phenomenex Strata-X cartridges employing 200μL human plasma. Chromatography was carried out on Waters Acquity UPLC BEH C 18 (50×2.1mm, 1.7μm particle size) analytical column under isocratic conditions using a mobile phase consisting of 4.0mm ammonium acetate-acetonitrile (15:85, v/v). The precursor→product ion transitions for nifedipine (m/z 347.2→315.2) and IS (m/z 353.1→318.1) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring and positive-ion mode. The method was validated over a wide dynamic concentration range of 0.050-150ng/mL. Matrix effect was assessed by post-column analyte infusion and the mean extraction recovery was 95.6% across four quality control levels. The method is rugged and rapid with a total run time of 1.2min and was applied to a bioequivalence study of 20mg nifedipine tablet formulation in 30 healthy Indian subjects under fasting condition. Assay reproducibility was confirmed by reanalysis of 116 incurred samples.