Spectrophotometric determination of metformin hydrochloride via oxidative coupling reaction with 1-naphthol in pharmaceutical and environmental water sample


AbstractA simple, rapid, accurate and sensitive spectrophotometric method for determination of metformin hydrochloride has been developed. The proposed method is based on the oxidation of 1-naphthol by sodium hypochlorite and coupling with metformin hydrochloride in the presence of sodium hydroxide to form an intense blue soluble product with maximum absorption at 580 nm. Beerˈs law is obeyed over the concentration range of 2-20µg/ml, with molar absorptivity of 3.66x104 l/mol.cm.The present method is considered to be simple because it does not need either heating or hydrolysis or solvent extraction steps. The ingredients often formulated with metformin hydrochloride have been shown not to interfere, and the proposed method is suitable for the routine determination of metformin hydrochloride. The method has been successfully applied for the determination of metformin hydrochloride in pure form, pharmaceutical preparations(Tablets) and environmental water sample .