Analytical Method Development and Validation of Metformin by Rp-HPLC

Metformin hydrochloride, a widely used biguanide antihyperglycemic agent, remains the first-line therapy for the management of type 2 diabetes mellitus due to its efficacy, safety, and cost-effectiveness. The present study focuses on the development and validation of a robust, precise, and reliable reversed-phase high-performance liquid chromatography (RP-HPLC) method for the quantitative estimation of metformin in bulk drug and pharmaceutical dosage forms. The method was developed using a C18 column with an optimized mobile phase consisting of a suitable buffer and organic solvent system, delivered at a controlled flow rate. Detection was carried out using UV spectroscopy at an optimized wavelength in the low UV range. The developed method was systematically optimized by evaluating critical parameters such as mobile phase composition, pH, flow rate, and column conditions to achieve acceptable retention time, peak symmetry, and resolution. The method was validated in accordance with ICH guidelines for specificity, linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), robustness, and system suitability. The results demonstrated excellent linearity with a high correlation coefficient, satisfactory recovery within acceptable limits, and low %RSD values indicating good precision and reproducibility. The method also proved to be stability-indicating, effectively separating metformin from its degradation products under various stress conditions. Its applicability was confirmed for routine quality control analysis of bulk drug and tablet formulations, as well as for bioanalytical and stability studies. Overall, the developed RP-HPLC method is simple, rapid, accurate, and cost-effective, making it suitable for routine pharmaceutical analysis and regulatory compliance.