Spectrophotometric determination of chlorpromazine hydrochloride using 4-amino benzoic acid by oxidative coupling reaction

A simple, rapid spectrophotometric method has been established for the determination of chlorpromazine hydrochloride (CPZH) in its pure form and in a tablet formulations. The suggested method is based on the oxidative coupling reaction with4-amino benzoic acid using KIO3 in acidic solution to produce a violet colored product with maximum absorption at λ=560 nm. The analytical data obtained throughout this as follows: The Beer’s law is obeyed over the concentration range of (10–70) µg ml−1, but the detection limit and quantification limit are 0.194 besides 0.588 µg ml−1 respectively. The correlation coefficient (r) for the calibration graph was found to be 0.9990, molar absorptivity of 6.00 × 103 L.mol −1.cm−1, and Sandell’s sensitivity index of 0.0592 µg.cm−2. Direct and standard addition procedures were applied to both standards and specimens of pharmaceutical and the results indicate that the suggested method was successfully applied for the determination of CPZH.