A novel, rapid, precise and accurate high performance liquid chromatographic method was developed and validated for the simultaneous determination of Sitagliptin phosphate and Simvastatin in bulk drug and pharmaceutical formulation. The components were separated on Ymc Cyano (150 mm × 4.6 mm I.D., 5 μm particle size) with a mobile phase composed of 20 mM ammonium formate and acetonitrile in the ratio of 50:50 v/v (Adjust the pH to 3.5 with 0.1% formic acid) at a flow rate of 1.2 mL/min. The response was measured at 218 nm. The peaks were detected at 5.33 minutes and 4.19 minutes for Sitagliptin phosphate and Simvastatin respectively. Calibration curves were found to be linear (r2=0.999 for both Sitagliptin phosphate and Simvastatin respectively) over the concentration range of 2.5-200 µg/mL for Sitagliptin phosphate and 1-80 µg/mL for Simvastatin. The method was validated for linearity, precision, accuracy, ruggedness and robustness. The proposed method can be applicable for simultaneous quantitation of Sitagliptin phosphate and Simvastatin in tablet dosage form. Validation results assured that the recommended method was specific, rapid, reliable and reproducible. Good percent recoveries and low % RSD reveals the suitability of the present method for analysis of Sitagliptin phosphate and Simvastatin in quality control laboratories.

Keywords: Sitagliptin; Simvastatin; RP-HPLC; Estimation.