Development and validation of stability-indicating assay method by UPLC for a fixed dose combination of atorvastatin and ezetimibe.

A stability-indicating ultra-performance liquid chromatography method was developed and validated for the simultaneous determination of a fixed dose combination of atorvastatin and ezetimibe in bulk drugs. The developed method was successfully applied to the simultaneous quantitative analysis of the combination drugs in tablet. The chromatographic separation was performed on a Kromasil Eternity C18 UHPLC column (2.5 µm, 2.1 × 50 mm) using a gradient elution of acetonitrile and ammonium acetate buffer (pH 6.70; 0.01M) as the mobile phase at a flow rate of 0.2 mL/min with column oven temperature of 40°C. Ultraviolet detection was performed at 245 nm. Total run time was 5 min, within which the primary compounds and their degradation products were separated. The method was validated for accuracy, repeatability, reproducibility and robustness. Linearity, limit of detection and limit of quantitation were established for atorvastatin and ezetimibe.