Quantitative determination of isradipine in dog plasma by an ultra performance liquid chromatography–tandem mass spectrometry method

Abstract

A simple, sensitive and specific ultra performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed for the analysis of isradipine in dog plasma. After extracted with organic solvent, dog plasma samples were analyzed on an Acquity UPLC BEH C18 column interfaced with a triple quadrupole tandem mass spectrometer in positive electrospray ionization mode. Acetonitrile:water:formic acid (80:20:0.3, v/v/v) was used as the mobile phase at a flow rate of 0.2 ml/min. The chromatographic run time of each sample was 1.4 min. The calibration curve in plasma was linear in the range of 0.1–40.0 ng/ml. The intra- and inter-day precision was within 13.5% in terms of relative standard deviation (RSD%) and the accuracy was required to be 96.5%–98.4%. The validated UPLC–MS/MS method was successfully applied in a pharmacokinetic study of controlled-release isradipine in dogs.