Development and Validation of RP-HPLC Method for Estimation of Vardenafil in Bulk and Pharmaceutical Formulation

A specific, accurate and precise reverse phase high performance liquid chromatographic method was developed and validated for the estimation of vardenafil in bulk and pharmaceutical formulation. A Hypersil BDS C 8, 5μ column having 250 x 4.6 mm internal diameter in isocratic mode with mobile phase containing buffer and acetonitrile (60:40, v/v) was used. The flow rate was 1.0 ml/min and effluents were monitored at 240.0 nm over the concentration range of 50-250 µg/ml. The retention time obtained for vardenafil was 5.4 min. The method was validated for linearity, accuracy, repeatability, precision, specificity (in terms of acid, alkali, peroxide and thermal degradation), limit of detection, limit of quantification and ruggedness. Chromatographic peak purity data demonstrated specificity of the method to estimate vardenafil in presence of degradation products.  Limit of detection and limit of quantification were found 0.0125 µg/ml and 0.025 µg/ml respectively. Accuracy in terms of recovery of vardenafil from tablet formulation was found to be above 98 % indicating that vardenafil can be estimated from tablet dosage form without interference from the excipients. The validation data proves the potential utility of the proposed method for the quantitative determination of vardenafil in tablet formulation.