New Validated Analytical Method for the Simultaneous Estimation of Metformin and Etrugliflozin in Combined Pharmaceutical Dosage Forms by Using RP-HPLC

Abstract

The present research focuses on the development and validation of a Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) method for the simultaneous estimation of Metformin and Etrugliflozine in combined pharmaceutical dosage forms. The primary objective of this study was to establish a simple, accurate, precise, and cost-effective analytical method suitable for routine quality control and stability analysis. Chromatographic separation was achieved using a BDS C18 column (150 × 4.6 mm, 5 µm) with a mobile phase consisting of phosphate buffer and acetonitrile in the ratio of 45:55 v/v, at a flow rate of 1.0 mL/min. Detection was performed at a wavelength of 224 nm, where both drugs exhibited significant absorbance. Under the optimized chromatographic conditions, sharp and symmetrical peaks were obtained with retention times of 2.186 minutes for Metformin and 2.908 minutes for Etrugliflozine, showing excellent resolution and separation. The developed method was validated as per the International Council for Harmonisation (ICH Q2 R1) guidelines. The method demonstrated good linearity over the concentration range of 50–300 µg/mL for Metformin and 0.75–4.5 µg/mL for Etrugliflozine, with correlation coefficients (R²) greater than 0.999. Accuracy studies showed mean recoveries between 98% and 102%, while precision results confirmed reproducibility with %RSD values below 2. The method also proved to be robust and specific, showing no interference from excipients or degradation products. Hence, the developed RP-HPLC method is rapid, reliable, and suitable for routine simultaneous analysis of Metformin and Etrugliflozine in combined dosage forms.