High-performance liquid chromatographic method with coulometric detection for the determination of buspirone in human plasma by means of a column-switching technique.

A reversed-phase high-performance liquid chromatographic method with electrochemical detection has been developed for the determination of buspirone from human plasma. The separation was carried out by using a Supelcosil ABZ+ plus C18 reversed-phase column and 0.05 M potassium dihydrogenphosphate (pH 6.5)-acetonitrile (7:3, v/v) as the mobile phase. The compounds were detected by coulometry. Buspirone and the internal standard were extracted from the human plasma using Bond-Elut C18 solid-phase extraction cartridges. Following removal of the the highly lipophilic plasma components we applied a column-switching technique which reduced the duration of HPLC measurement from 60 min to 15 min. The limit of quantitation was found to be 100 pg/ml plasma.