Development and validation of a liquid chromatographic-tandem mass spectrometric method for the determination of pibutidine in human urine

A liquid chromatographic-tandem mass spectrometric method for the rapid qua ntitative determination of pibutidine, an H-2-receptor antagonist, in human urine has been developed and validated over the concentration range 0.1-25 .6 mu g ml(-1). Urine samples were prepared based on a simple dilution with 0.05% acetic acid, followed by reversed-phase Liquid chromatographic separ ation. Pibutidine and its internal standard (H-2(10)-pibutidine) were ioniz ed using an electrospray ionization interface and detected by tandem mass s pectrometry in the selected reaction-monitoring mode. Completed validation demonstrated the method to be robust, accurate, precise and specific for th e direct quantification of pibutidine in human urine. This method has enabl ed investigation of the urinary excretion of pibutidine following oral admi nistration of pibutidine hydrochloride to healthy subjects. (C) 2000 Elsevi er Science B.V. All rights reserved.