HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHODS FOR THE ANALYSIS OF HALOPERIDOL AND CHLORPROMAZINE METABOLISM IN-VITRO BY PURIFIED CYTOCHROME-P450 ISOFORMS

Sensitive HPLC methods for the resolution and quantitation of metaboli tes of both haloperidol and chlorpromazine metabolism have been develo ped for use in in vitro reconstitution assays with purified P450 isofo rms. Separation of haloperidol metabolites was accomplished using a Hy persil CPS column with a mobile phase of 67% acetonitrile and 10 mM am monium acetate, pH 5.4. Separation of chlorpromazine metabolites was a chieved using an Ultrasphere cyano column with a mobile phase of 87.5% acetonitrile, 5% methanol, 3% 0.12 M sodium acetate, 3% 0.12 M ammoni um acetate, 0.01% diethylamine and 0.01% triethylamine, pH 9.5. Sharp resolution was observed for haloperidol and three of its major metabol ites and for chlorpromazine and five of its major metabolites. Varying levels and combinations of these metabolites are formed during in vit ro incubations of parent compound with purified P450 isoforms 1A1 and 2B1 in a reconstituted system. (C) 1998 Elsevier Science B.V. All righ ts reserved.