STABILITY INDICATING HPLC METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION OF GLIMEPIRIDE AND SITAGLIPTIN PHOSPHATE MONOHYDRATE IN SYNTHETIC MIXTURE

A new, precise, rapid and accurate RP-HPLC method was developed for the simultaneous estimation of Glimepiride and Sitagliptin phosphate monohydrate in synthetic mixture.RP-HPLC method was designed using an HPLC system equipped PDA detector.After optimization of good chromatographic separation was achieved with a mixture of Acetonitrile: Methanol: Phosphate buffer (pH-4.5 with orthophosphoric acid) in the volume ratio of 35:30:35 %v/v/v as the mobile phase with, C18 column (250 nm x 4.6 mm, 5 m) as stationary phase at flow rate of 1 mL/min and detection wavelength of 240 nm.The retention time of Dexamethasone and Metoclopramide was found to be 5.640 min and 3.504 min respectively.The linearity of this method was found in the concentration range of 50 to 300 g/ml for Glimepiride and Sitagliptin phosphate monohydrate.The correlation coefficient r 2 value was found to be 0.994 for Glimepiride and 0.9984 for Sitagliptin phosphate monohydrate.The method was extensively validated according to ICH guidelines for Linearity, Range, Precision, specificity and Robustness.