Kinetic spectrophotometric method for determination of perphenazine based on monitoring the oxidation intermediate by applying a stopped-flow technique

A novel and high-sensitive stopped-flow kinetic spectrophotometic method for the determination of perphenazine based on monitoring the variation of absorbance of the intermediate within a few seconds has been developed. The optimum conditions for various parameters on which the forming of the intermediate depends, were investigated. It was found that the initial reaction rate increased linearly with an increase in the perphenazine concentration in the range from 1.0 x 10(-5) to 1.6 x 10(-4) M. The detection limit was calculated to be 5.3 x 10(-6) M. The kinetics of the reaction was established by the aid of single-mixing or double-mixing stopped-flow techniques, a successive reaction model was proposed to analyze and simulate the reaction. The influence of both ascorbic acid and NADH on the time courses was also investigated. (C) 2004 Elsevier B.V. All rights reserved.