Modern spectrophotometric approach for assessment chlorpromazine hydrochloride drug

A rapid,simple, and sensitive spectrophotometric approach for theassessment of microgram amounts of chlorpromazine hydrochloride drug in aqueous solution is described. The method is based on the oxidative coupling reaction between chlorpromazinehydrochloride and N-methyl-p-hydroxy aniline (metol)in thepresence of sodium periodate andhydrochloride acid to form an intense redcolored product withmaximum absorption at 526 nm. Beer’s law is obeyed over the concentrationrange of(1-20)μg.ml-1 with molar absorptivity of 1.597x104l.mol-1.cm-1 and Sandell`s sensitivity of 0.022μg.cm-2. The approach does not resort totemperature control or to solvent extraction. Theoptimum conditions for all color development are described and the proposedmethod has been successfully applied for the assessment of chlorpromazinehydrochloride in bulk drug and pharmaceutical preparations(Largactil drug). The commonexcipients and additives did not interfere in this approach .