Abstract

Spectrophotometric microdetermination of anti-diabetic drug metformin HCl in pharmaceutical formulation and biological fluids

Author(s): Manal S.Kamel, Elmorsy Khaled, Atef M.Homoda, Barsoum N.Barsoum

Two simple, sensitive and accurate spectrophotometric methods have been proposed for the determination ofmetformin (Mf) pharmaceutical formulations and biological fluids. The methods are based on the measurement of absorbances of tris (o-phenanthroline) iron (II) [FPL, method A] and tris (bipyridyl) iron (II) [FBL,methodB] complexes at 510 and at 520 nm, respectively. Reaction conditions have been optimized to obtain coloured complexes of higher sensitivity and longer stability. The absorbances were found to increase linearlywith increase in concentrations ofMfwhich were corroborated by correlation coefficient values. The complexes obeyed BeerÂ’s lawover the concentration range of 0.2–6.00.02-6.0ìgml-1 forMf. The proposed methods were successfully applied to the determination ofmetformin HCl in bulk drugs, pharmaceutical formulations and biological fluids (obtained from diabetic patients undergoing treatment with metformin, HCl) without interference by the common co-formulated substances. Statistical comparison of the results with the reference method showed good concurrence and indicated no significant difference in accuracy and precision.