Analytical Method development and Method validation for the simultaneous estimation of Metformin HCL and Linagliptin in Bulk and tablet Dosage Form by RP-HPLC Method

A rapid, highly sensitive, economical and accurate RP-HPLC method was developed for simultaneous estimation of Metformin HCL and Linagliptin in Bulk and Pharmaceutical Dosage form. The separation was achieved by Hypersil C18 column (250 × 4.6 mm, 5 μ particle size) with mobile phase consisting of phosphate buffer (pH 5.6, diluted with orthophosphoric acid), methanol and acetonitrile in the ratio of 40:5:55 v/v, using flow rate 1.0 mL/min and eluents monitored at 233nm .The developed method was validated as per ICH guidelines for specificity, linearity, precision, accuracy, robustness, limit of detection and limit of quantification. The retention times of Linagliptin and Metformin were 5.4 and 6.6 min respectively. The linearity was found to be in the range of 125-750 μg/mL and 0.625-3.75 μg/mL for Metformin and Linagliptin respectively, had regression coefficients (R 2 ) 0.999. The proposed method was successfully applied for simultaneous estimation of both drugs in Pharmaceutical formulation.