A Rp-hplc Method for Determination of Diclofenac with Rabeprazole in Solid Dosage Form

To develop and validate simple, reproducible, stability indicating reverse phase high performance liquid chromatography for the simultaneous determination of Rebeprazole and Diclofenac in pharmaceutical solid dosage form. The method was based on HPLC separation of both drugs in reverse phase mode using Phenomenox C18 column with Waters HPLC system by using mobile phase composition of acetonitrile and 50mM ammonium acetate buffer (pH 3.6) (60:40 v/v) at flow rate 1 ml/min. Detection wavelength used at 254 nm. Loratidine was used as internal standard. Linearity was obtained in the concentration range of 1.0-3.2 μg/ml for rabeprazole and 6.0-16.0 μg/ml diclofenac. The mean values of the correlation coefficient, slope and intercept for rabeprazole and diclofenac were 0.998, 0.0186, + 0.010 and 0.999, 0.0193, -0.0098 respectively. The method was validated for precision, robustness and recovery. The limit of detection (LOD) and limit of quantitation (LOQ) for rabeprazole 30, 95 ng/ml and for diclofenac 125, 375 ng/ml respectively. Statistical analysis showed that the method is reproducible and selective for the estimation of rabeprazole and diclofenac in pharmaceutical formulations. This method can be applicable for bioequivalence studies.