Method Development and Validation for Simultaneous estimation of Metformin Hcl and Sitagliptin by RP-HPLC in Tablet Dosage Form

Abstract

method has been developed and subsequently validated for the simultaneous estimation of Metformin
Hydrochloride and Sitagliptin Phosphate in pure and tablet formulation. The proposed method is based on the
separation of the two drugs in reversed-phase mode using zodiac C18 (250×4.6 mm, 5 μm particle size). The
optimum mobile phase consisted of phosphate buffer : acetonitrile in the ratio of 55:45 v/v (Phosphate buffer pH
5.8 was adjusted with sodium hydroxide) was selected as a mobile phase, flow rate of 1.0 ml/min and UV
detection was set at 244 nm. The retention times were 2.1 and 4.90 min for Metformin Hydrochloride and
Sitagliptin Phosphate respectively. The method was validated according to ICH guidelines. It was found to be
accurate and reproducible. Linearity was obtained in the concentration range of 75-175 μg/ml for Metformin
Hydrochloride and 7.5-17.5 μg/ml Sitagliptin Phosphate. Mean percent recovery of samples at each level for
both drugs were found in the range of 99.70% for Metformin Hydrochloride and 99.40s % for Sitagliptin
Phosphate. The proposed method can be successfully applied in the quality control of bulk and pharmaceutical
dosage forms.