Development and validation of reversed phase high performance liquid chromatography method for simultaneous estimation of Nebivolol HCl and Cilnidipine in combined tablet dosage form

Objective: A simple, precise and accurate reversed phase high-performance liquid chromatography (RP-HPLC) method has been developed and subsequently validated for the simultaneous estimation of Nebivolol HCl and Cilnidipine in tablet formulation. Methods: The adequate separation was carried out using Grace Smart C18 column (250 mm x 4.6 mm, 5 μm particle size), mixture of 0.05 M Potassium dihydrogen phosphate PH 5.0 and Methanol 30:70 % v/v as a mobile phase with a flow rate of 1 ml/min and the effluent was monitored at 225 nm using PDA detector. The retention time of Nebivolol HCl and Cilnidipine were 4.057 min and 6.470 min respectively. Results: Linearity for Nebivolol HCl and Cilnidipine were found in the range of 5-15 µg/ml and 10-30 µg/ml (R 2 = 0.998) respectively. The accuracy of the present method was evaluated at 80%, 100% and 120%. The % recoveries of both drugs were found to be in range of 99.698-100.108% and 99.497-99.512% for Nebivolol HCl and Cilnidipine respectively. Precision studies were carried out and the RSD values were less than two. The method was found to be robust. Conclusions: The proposed method was found to be specific, accurate, precise and robust can be used for simultaneous estimation of these drugs in tablet dosage form.