DETERMINATION OF PILOCARPINE, ISOPILOCARPINE, PILOCARPIC ACID AND ISOPILOCARPIC ACID IN HUMAN PLASMA AND URINE BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH TANDEM MASS-SPECTROMETRIC DETECTION

A method is described for the determination of pilocarpine and its deg radation products isopilocarpine, pilocarpic acid and isopilocarpic ac id in human plasma and urine. The method is based on a simple sample p reparation step - ultrafiltration for plasma and dilution for urine sa mples - followed by a reversed-phase liquid chromatographic separation of the analytes and detection by means of tandem mass spectrometry. P arameters affecting the performance of these steps are discussed. The high sensitivity and selectivity of the method allow low ng/ml concent rations to be determined for all compounds in plasma and undiluted uri ne, which enables the investigation of the metabolic fate and eliminat ion of pilocarpine after oral administration to humans. (C) 1998 Elsev ier Science B.V.