Voltammetric determination of chlorpromazine hydrochloride and promethazine hydrochloride with the use of multivariate calibration

The voltammetric behavior of antipsychotic drugs, such as, chlorpromazine h ydrochloride and promethazine hydrochloride has been investigated at a glas sy carbon electrode in Britton-Robinson buffer of pH 9, It was found by app lying the differential pulse stripping voltammetry (DPSV) that both chlorpr omazine hydrochloride and promethazine hydrochloride had well formed oxidat ion voltammetric waves, with the peak potential for chlorpromazine hydrochl oride at 620 mV, and for the two peaks of promethazine hydrochloride at 444 and 668 mV. The calibrations were linear for chlorpromazine hydrochloride and promethazine hydrochloride in the concentration ranges of 0.05-1.2 and 0.1-1 mg 1(-1), respectively. However, the voltammetric peaks of these two drugs, seriously overlap and it is difficult to determine them individually from a response of a drug mixture. In this work, a method for the simultan eous determination of these two drugs is proposed, and is based on their ox idation at the glassy carbon electrode. The interpretation of the complex v oltammograms is achieved with the aid of chemometric methods, such as, clas sical least squares (CLS), principal component regression (PCR) and partial least squares (PLS). The proposed method was applied to determine these tw o drugs in a set of synthetic mixtures and blood samples, and in general, s atisfactory results were obtained, (C) 2001 Elsevier Science B.V. All right s reserved.