Validated RP-HPLC Method for Estimation of Atorvastatin and Ezetimibe in Tablets

Abstract

A simple, sensitive and reproducible RP-HPLC method was developed and validated for the simultaneous estimation of Atorvastatin and Ezetimibe in combined tablet dosage form. Chromatographic separation was achieved on a Purospher C18 column (250 × 4.6 mm, 5 µm) using a mobile phase consisting of ammonium acetate buffer and acetonitrile in the ratio of 60:40 (v/v), delivered at a flow rate of 1.5 mL/min in isocratic mode. Detection was carried out at 248 nm with an injection volume of 20 µL, and the retention times of Atorvastatin and Ezetimibe were found to be approximately 16.0 and 10.0 minutes, respectively. The method was validated as per ICH guidelines. Linearity was observed in the range of 80–120 µg/mL for Atorvastatin and 40–60 µg/mL for Ezetimibe, with correlation coefficients (r) of 0.9999 for both drugs. System precision and method precision studies showed low %RSD values, indicating excellent repeatability. Accuracy, evaluated by recovery studies at 80%, 100% and 120% levels, was within acceptable limits for both drugs. The method demonstrated good specificity, with no interference from tablet excipients, and satisfactory system suitability parameters. The limits of detection and quantification were 2.150 and 6.51 µg/mL for Atorvastatin, and 0.0945 and 0.286 µg/mL for Ezetimibe, respectively, confirming the sensitivity of the method. The proposed RP-HPLC method is thus suitable for routine quality control analysis of Atorvastatin and Ezetimibe in combined tablet formulations.