VALIDATED STABILITY INDICATING RP -HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF FURAZOLIDONE AND METRONIDAZOLE IN COMBINED PHARMACEUTICAL DOSAGE FORMS

A simple, selective, precise and accurate stability-indicating highperformance liquid chromatographic method for the analysis of metronidazole, furazolidone and its degradation products in tablet dosage form was developed and validated. The stability indicating ability of the method was determined by performing forced degradation studies which indicated susceptibility of the drug under basic and thermal conditions. Separation of drug from its degradation products was achieved by isocratic elution using a mobile phase consisting of acetonitrile: Methanol: phosphate buffer (10:40:50) through an XTerra C18 column (150 x 4.6 mm, 5 μ) at a flow rate of 1ml/min with UV-detection(270nm) at ambient temperature. Analytical performance of the proposed HPLC procedure was statistically validated with respect to linearity, precision, accuracy, specificity, robustness, detection and quantification limits. The linearity ranges were 30–150 and 10–50µg/ml for metronidazole and furazolidone respectively with correlation coefficients >0.9993. The two drugs were subjected to stress conditions of acidic and alkaline hydrolysis, oxidation, thermal and photolysis degradation. The proposed method proved to be stability-indicating by resolution of the analytes from their forced-degradation products.