Simultaneous Determination of Simvastatin and Ezetimibe in Tablets by HPLC

A reverse phase high performance liquid chromatographic method was developed for the simultaneous determination of simvastatin and ezetimibe in tablet dosage forms. The separation was effected on a C18 Supelcosil column ( 250 mm x 4.6 mm; 5 mu) using a mobile phase consisting of 0.01 M ammonium acetate buffer and acetonitrile ( 35: 65 v/v) at a flow rate of 1 mL/min. The detection was made at 240 nm. The retention times for ezetimibe and simvastatin were 5.9 and 8.5 min respectively. Calibration curves were linear over the ranges of 0.5-40 mu g/mL for simvastatin and 2.5-50 mu g/mL for ezetimibe. The proposed method was validated as per the ICH and USP guidelines. The method is accurate and precise and found to be suitable for the quantitative analysis of both the drugs individually and in combination in tablet dosage forms.