ESTIMATION OF SOLID DOSAGE FORMS OF COMBINED ANTIHYPERLIPIDAEMIC DRUGS BY VALIDATED REVERSE PHASE LIQUID CHROMATOGRAPHIC METHOD

A reverse-phase high-performance liquid chromate-graphic method (RP-HPLC) was developed for the simultaneous estimation of combined dosage form of ezetimibe with simvastatin and rosuvastatin using RP-C18 column. For estimation of ezetimibe and simvastatin, the mobile phase (acetonitrile: water and pH adjusted to 4.5 with acetic acid) was pumped at a flow rate of 0.8 ml/min in the ratio of 85:15% v/v and the eluents were monitored at 234 nm. For the estimation of ezetimibe and rosuvastatin the mobile phase (acetonitrile: water and pH adjusted to 4.5 with acetic acid) was pumped at a flow rate of 0.8 ml/min in the ratio of 75:25% v/v and the eluents ezetimibe and rosuvastatin were monitored at 245 nm. Linearity was obtained in the concentration range of 2-12 μg/ml for ezetimibe in both the mobile phase, 2-12 μg/ml for simvastatin, and 2-12 μg/ml for rosuvastatin. The method was statistically validated, and RSD was found to be less than 2% indicating high degree of accuracy and precision of the proposed method. Due to its simplicity, rapidness, high precision, and accuracy, the proposed RP-HPLC method can be applied for simultaneous determination of ezetimibe and its combined drug simvastatin and rosuvastatin from the bulk and formulation.