Quantitative determination of pimozide in human plasma by liquid chromatography-mass spectrometry and its application in a bioequivalence study.

Author(s): Yan M, Li HD, Chen BM, Liu XL, Xu P, Zhu YG.

Affiliation(s): Clinical Pharmacy & Pharmacology Research Institute, The Second Xiangya Hospital of Central South University, 139# Middle Renmin Road, Changsha, Hunan Province 410011, PR China.

Publication date & source: 2010, J Pharm Biomed Anal. , 51(5):1161-4

A simple, sensitive and specific LC-ESI/MS method was developed for the determination of pimozide in human plasma. Pimozide and cinnarizine (internal standard) were isolated from plasma samples by liquid-liquid extraction. The chromatographic separation was accomplished on a Thermo Hypersil-HyPURITY C18 reversed-phase column (150mmx2.1mm, i.d., 5microm) with the mobile phase consisting of 5mM ammonium acetate (pH 3.5, adjusted with acetic acid)-methanol-acetonitrile (39:5:56, v/v/v). The lower limit of quantification was 0.02ng/mL, and the assay exhibited a linear range of 0.025-12.800ng/mL. The established method has been successfully applied to a bioequivalence study of 2 pimozide formulations in 32 healthy male Chinese volunteers.