[Differential kinetic spectrophotometric determination of chlorpromazine hydrochloride and promethazine hydrochloride by chemometric method].

Chlorpromazine hydrochloride and promethazine hydrochloride were oxidized fastly resulting in red intermediate product, which was then gradually changed into a colorless product by ammonium cerous sulfate in appropriate acidic medium. The chemometric multivariate calibration methods, such as partial least squares (PLS) and principal components regression (PCR) were applied to the resolution of the kinetic curves to determine these two compounds. The linear ranges are 8.3 - 66.7 mg x L(-1) and 3.3 - 26.7 mg x L(-1) for chlorpromazine and promethazine, respectively. The limits of detections are 2.32 and 0.95 mg x L(-1) for these two compounds, respectively. This method was successfully applied to the analysis of pharmaceutical samples with satisfied results.