RP-HPLC method for the quantification of Metformin and Rosiglitazone in bulk and combined tablet dosage form: method development and validation
A rapid, simple and selective reverse phase high performance liquid chromatographic method for simultaneous estimation of metformin and rosiglitazone in bulk and combined tablet dosage form was developed and validated. The method employed Phenomenex (150 mm x 4.6 mm, 5-µm particle size) C8 analytical column as the stationary phase. The solvent system consisted of orthophosphoric acid (0.1%) and methanol in the ratio of 60:40 (v/v). The detection and quantification of metformin and rosiglitazone was carried out with PDA detector set at 220 nm. Retention time for metformin and rosiglitazone were 2.176 and 2.919 min, respectively. Linear regression analysis data for the calibration curves showed good linear relationship with R2 = 0.9995 with respect to peak area in the concentration range 500-1500 µg/ml for metformin and R2 = 0.9999 with respect to peak area in the concentration range 1-30 µg/ml for rosiglitazone. The method was validated for sensitivity, precision, accuracy, selectivity, recovery and robustness. The limits of detection & quantitation were 7.151 & 23.838 µg/ml for metformin and 0.012 & 0.043 µg/ml for rosiglitazone, respectively. Statistical validation analysis proved that the method is selective, precise, accurate and robust for the estimation of metformin and rosiglitazone.