A simple and convenient method for the simultaneous in vitro study of metformin and glimepiride tablets

A simple and convenient method was developed for the simultaneous determination of metformin HCl and glimepiride in tablet dosage form of different pharmaceuticals companies. This method was validated and proved to be applicable for assay determination in intermediate and finished staged. More over a single medium dissolution of metformin HCl and glimepiride was established and the media was evaluated for comparative studies for different formulations. Reverse phase HPLC equipped with UV detector was used for the determination of metformin HCl and glimepiride. A mixture of acetonitrile and ammonium acetate buffer 0.05M pH 3.0 was used as mobile phase at flow rate of 1.0ml/min. Promocil C18 5µ 100Aº 4.6 x 100mm C18 silica column was used and detection was carried out at 270nm. Method was found to be linear over the range of 4ppm to 16ppm for glimepiride and 170ppm to 680ppm for metformin HCl. Regression co-efficient were found to be 0.9949 and 0.9864 for glimepiride and metformin HCl respectively. Dissolution was performed in 500ml 0.2% sodium lauryl sulfate at 37°C for 45min using paddle apparatus. Dissolution of glimepiride was found to be 98.60% and 101.08% in Orinase Met1 tablet and Amaryl M tablet respectively whereas metformin was found 99.41% and 98.59% in Orinase Met 1 tablet and Amaryl M tablet. RSD for all the dissolutions was less than 2.0% after completion.