Second Order Derivative spectroscopy.

A simple, accurate, and precise UV spectrophotometric method has been developed and validated for simultaneous estimation of Cilnidipine and Valsartan in synthetic mixture. The estimation of drugs was done by Second Order Derivative spectrophotometric method using 219 nm and 227 nm wavelength. Methanol was used as a solvent. The Linearity was obtained in the concentration range of 2-10 µg/ml for Cilnidipine and 5-25 µg/ml for Valsartan with R2 0.9994 and 0.9980 respectively. Accuracy was determined by recovery studies and showed % recovery between 98 to 102 % for both the drugs. The LOD and LOQ values of Cilnidipine were found to be 0.33 and 1.01 and for Valsartan values were found to be 0.18 and 0.55. The developed method was validated as per the ICH Guidelines Q2 (R1).