Sensitive spectrophotometric determination of some dibenzazepine drugs with diazotized P-phenylenediamine dihydrochloride

A simple, sensitive and selective spectrophotometric procedure was develope d for the determination of imipramine hydrochloride, desipramine hydrochlor ide, clomipramine hydrochloride and trimipramine maleate belonging to diben zazepine class of drugs. The method is based on the interaction of diazotiz ed p-phenylenediamine dihydrochloride with the drug in sulphuric acid mediu m. The resulting chromophore was measured at 565 nm, and was stable for abo ut 2.5 hr. The commonly encountered excipients and additives do not interfe re with the determination. Dibenzazepine drugs can be determined in the ran ge of 0.1-4.0 mug/ml, with a relative standard deviation of 1.92% for ten r eplicate measurement of 2.0 mug/ml dibenzazepine drugs. Results from the an alysis of preformulations and commercial tablets by this procedure agree we ll with those of the official method.