Abstract
Author(s): T. Raja1and A. Lakshmana Rao2*
A simple, accurate, precise and rapid reversed-phase high performance liquid chromatographic (RP-HPLC) 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 Xterra Symmetry C-8 analytical column (100×4.6 mm I.D., 5 μm particle size). The optimum mobile phase consisted of methanol:acetonitrile:phosphate buffer inthe ratio of 20:35:45 v/v/v (Phosphate buffer pH 8 was adjusted with sodium hydroxide) was selectedas a mobile phase, flow rate of 1.0 ml/min and UV detection was set at 254 nm. The retention times were 3.69 and 4.90 min forMetformin Hydrochloride and Sitagliptin Phosphaterespectively. The method was validated according to ICH guidelines. It was found to be accurate and reproducible. Linearity was obtained in the concentration range of 100-300 μg/ml for Metformin Hydrochlorideand 10-30 μg/ml Sitagliptin Phosphate. Mean percent recovery of samples at each level for both drugs were found in the range of 101% for Metformin Hydrochloride and 102% for Sitagliptin Phosphate. The proposed method can be successfully applied in the quality control of bulk and pharmaceutical dosage forms