SENSITIVE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHOD FOR A DOPAMINE-RECEPTOR AGONIST, CI-1007, AND ITS METABOLITE PD-147693 IN MONKEY PLASMA

A sensitive gradient high-performance liquid chromatographic (HPLC) me thod for the simultaneous quantitation of a dopamine autoreceptor agon ist CI-1007 (I) and its metabolite PD 147693 (II) is described. Monkey plasma samples were purified by liquid-liquid extraction using hexane . Liquid chromatographic separation was achieved on two C-18 analytica l columns (installed in series) using gradient elution. Column effluen t was monitored using a fluorescence detector programmed to change wav elengths at specified times. Minimum quantitation limits of I and II w ere 3.0 and 5.0 ng/ml, respectively, for a plasma sample volume of 0.1 00 ml. Linearity was demonstrated up to 300 ng/ml. The assay has been applied to the analysis of I and II in plasma from monkeys following i ntravenous and oral doses of I.