RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION AND STABILITY INDICATING STUDY OF METFORMIN AND LINAGLIPTIN IN PURE AND PHARMACEUTICAL DOSAGE FORMS

摘要

Objective : The objective of this study was to develop a simple, efficient, specific, precise and accurate Reverse phase High Performance liquid chromatography method for the simultaneous estimation of Metformin and Linagliptin Pharmaceutical Dosage form. Methods : The separation method was carried out using reverse phase C18 column, Inertsil ODS – 3V (250 mm x 4.6 mm x 5μm). The mobile phase used was a mixture of Phosphate buffer (1.625 g of Potassium Di Hydrogen Ortho Phosphate and 0.3 g of Di Potassium Hydrogen Ortho Phosphate in 550 ml water) pH 4.5 and Acetonitrile in the ratio of 60:40 (v/v) at isocratic mode. The flow rate was 1.0 mL/min, column temperature was 30°C and eluents were monitored at 280 nm using waters 2695 alliance HPLC instrument equipped with the Waters 2998 PDA detector and Empower 2 software. Results: With the optimized method, the retention times of Metformin and Linagliptinwere found to be 3.048 and 4.457 respectively, with theoretical plate count and asymmetry as per the ICH limits. The method has shown a good linearity in the concentration range of 500-3000μg/ml from Metformin and 2.5-15μg/mL for Linagliptin with Regression coefficient (R2) of 0.99 and 0.99. The percentage assays were found to be 99.28% and 99.54% respectively for Metformin and Linagliptin. The method was found to be accurate (with percentage mean recoveries 100% for Metformin HCl and 100% for Linagliptin), precise, robust, stable and Degradation studies are conducted under various conditions. Conclusion: The proposed method was validated in accordance with ICH guidelines and hence, can be successfully applied to the simultaneous estimation of Metformin and Linagliptin tablet formulations. Keywords: Metformin and Linagliptin, Simultaneous estimation, Reverse phase HPLC, Validation, Degradation studies.