Simultaneous estimation of cilnidipine and Valsartan by RP-HPLC in tablet formulation

Abstract

A new high performance liquid chromatography method was developed and validated for the quantitation of Cilnidipine and Valsartan in pharmaceutical formulations. Determination was performed using an ODS C18, 250mm x 4.6mm, 5μm column, a mobile phase containing Methanol: Water (85:15) pH 3 adjusts with ortho-phosphoric acid in isocratic flow rate 1.0 mLmin-1. The method was validated with respect to linearity, precision, robustness, and accuracy. The calibration graphs ranged from 1-5 μg/mL in Cilnidipine and 8-40 μg/mL Valsartan Intra- and interday relative standard deviation values for the standard solutions were 0.5%, 1.64% and 0.22%, 1.62 %. Robustness of relative standard deviation values was 0.334, 0.101 respectively. Total recoveries of Cilnidipine and Valsartan from the laboratory prepared mixtures were 98.94 % and 99.04 % respectively.