DEVELOPMENT AND VALIDATION OF RP - HPLC METHOD FOR SIMULTANEOUS ESTIMATIONOF OLMESARTAN MEDOXOMIL AND METOPROLOL SUCCINATE IN BULK AND DOSAGE FORM

A simple, specific, accurate and precise reverse phase high performance liquid chromatographic method was developed for the simultaneous estimation of olmesartan medoxomil and metoprolol succinate intablet dosage form. A Phenomenex-C18, 5 mcm column 250 mm 4.6 mm in gradient mode, with mobile phase containing phosphate buffer, acetonitrile and methanol in proportion of 65:35 v/v, pH 5.5 adjusted with orthophosphoric acid were used. The flow rate was 1 mL/min, and effluent was monitored at 254 nm.The retention time of olmesartan medoxomil and metoprolol succinate were 8.02 and 5.36 min respectively, and the resolution factor was 9.0. Linearity range for olmesartan medoxomil and metoprololsuccinate was 5-30 mcg mL-1 and 5-70 mcg mL-1 respectively. The proposed method is accurate, precise,specific and rapid for simultaneous estimation of ol mesartan medoxomil and metoprolol succinate in tablet dosage form.