Application of an electrochemical detector to the determination of procarbazine hydrochloride by high-performace liquid chromtography

Abstract An amperometric flow-through detector with a carbon paste working electrode was utilized as a high-performance liquid chromatographic (HPLC) detector to determine procarbazine hydrochloride, an antineoplastic agent, in both buffer solution and biological fluids. The HPLC system included an amino-cyano stationary phase and an aqueous (pH 7)-methanolic mobile phase which enabled the separation of procarbazine from its only electroactive degradation product, N-isoprophyl- a - (2-methylhydrazono)- p -toluamide. The electrochemical detector, with an approximate limit of detection of 2 ng procarbazine injected, was 20 times more sensitive to procarbazine than a typical UV detector. The low dead volume (I μl) and superior selectivity of the electrochemical detector enabled the HPLC determination of procarbazine in untreated human urine and plasma.