Determination of Cinepazide Maleate in Rat Plasma by LLE Using LC–MS–MS

A liquid chromatography tandem mass spectrometry method employing electrospray ionization has been developed for the determination of cinepazide maleate in rat plasma using alprazolam as the internal standard. Liquid–liquid extraction was used for sample preparation and the analysis was achieved on a C18 reversed phase column. The method was validated over the concentration range 1–2,000 ng mL−1 in rat plasma. The intra-day and inter-day precision of cinepazide maleate expressed as RSD < 10% and the relative error (RE) did not exceed 10%. This validated method is a novel technique for sample preparation and quantitation, which was successfully applied to pharmacokinetic studies of cinepazide maleate in rats following a single oral administration dose of 10 mg kg−1.