SEQUENTIAL OPTIMIZATION OF A FLOW-INJECTION SPECTROPHOTOMETRIC METHODFOR THE ASSAY OF CHLORPROMAZINE IN PHARMACEUTICAL PREPARATIONS

A new simple flow injection spectrophotometric method for the assay of chlorpromazine using cerium(IV) in sulfuric acid media was developed. The oxidized form of the drug was monitored at the maximum absorbance of 526 nm. The optimum conditions were 0.035 M sulfuric acid, 3.80 x 10(-3) M cerium(IV), flow rate 4.85 ml/min, coil length 45 cm and samp le size 110 mm(3). Optimization was carried out by the modified simple x method. Response surface methodology was employed to investigate the ruggedness of the method. A sampling frequency of 120 hr(-1) was atta ined. Relative standard deviations for standard sample were usually le ss than 0.75. The method was applied to the determination of chlorprom azine in proprietary drugs and results were statistically compared wit h the official British Pharmacopoeia (BP) method.