DETERMINATION OF TIMIPERONE IN RAT PLASMA BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH ELECTROCHEMICAL DETECTION

We report a sensitive new method for the determination of timiperone i n rat plasma by using high-performance liquid chromatography with elec trochemical detection. The method involves extraction of plasma sample s with heptane-isoamyl alcohol at pH>8, followed by back-extraction in to dilute acetic acid. Separation was accomplished by reversed-phase h igh-performance liquid chromatography on an ODS column with the mobile phase consisting of 0.1 M phosphate buffer (pH 3.5)-acetonitrile-meth anol (65:20:15, v/v). Recovery was greater than 80%. Calibration curve was linear over the concentration range 0.5-50.0 ng/ml. The limit of quantitation of timiperone was 0.5 ng/ml plasma.