Quantification and Validation of Simvastatin and Ezetimibe in Bulk Drugs and Combined Dosage Form by Reverse Phase Liquid Chromatographic Method (RPLC)

A simple, time saving, precise and cost effective reverse phase high performance liquid chromatographic (RP-HPLC) method developement was achieved for the determination and estimation of simvastatin and ezetimibe in its pure form and combined formulation. Separation was achieved by using Zorbax (100 × 4.6 mm, 5μ) C 18 column with mobile phase consisted of acetonitrile and methanol in a ratio of 60:40 (v/v). The separation was observed at 232 nm with flow rate adjusted to 1 ml/min. Simvastatin and ezetimibe were retained at 9.603 and 3.861 minutes successively. Validation was done for the developed method based upon different parameters like linearity, accuracy, precision, limit of detection and limit of quantitation. Simvastatin and ezetimibe obey Beer-Lambert’s law in the range of 20.0-160µg/ml and 5-40µg/ml respectively. The % recoveries of simvastatin and ezetimibe were found to be 101.25% and 102.03% respectively from the tablet formulation. The limit of detection of simvastatin and ezetimibe were found to be 1.34µg/ml and 0.253µg/ml successively. The limit of quantitation of simvastatin and ezetimibe were found to be 4.489µg/ml and 0.846µg/ml successively. The established method is suitable for simultaneous estimation of simvastatin and ezetimibe in their pure forms and combined formulation. Key words : Simvastatin, Ezetimibe, RP-HPLC, Simultaneous estimation.