Abstract
Spectrophotometric Investigations On The Assay Of Phenothiazine Drugs
A rapid, accurate and sensitive spectrophotometric method for the quantitative determination of four phenothiazine drugs either in pure form or in pharmaceutical preparations has been developed. The method is based on the development of red coloured products by the interaction of phenothiazines with diazotised anthranilic acid in hydrochloric acid medium. The reaction proceeds via the oxidation of the phenothiazine nucleus into a semiquinonoid radical. The optimum reaction conditions and other analytical parameters are evaluated. The common excipients employed do not interfere in the determination of phenothiazine drugs. Results of analysis of pure drugs and their dosage forms by the proposed method are in good agreement with those of the official method.
