Analytical Method Development and Validation of Metformin, Voglibose, Glimepiride in Bulk and Combined Tablet Dosage Form by Gradient RP-HPLC

Background: A simple, sensitive, linear, precise, and accurate method by gradient reversed-phase-high performance liquid chromatography for the simultaneous estimation of metformin (MET), voglibose (VOG) and glimepiride (GLI) in bulk and in their combined tablet dosage form was developed and validated. Materials and Methods: The separation of the three drugs was based on the use of Inertsil ODS 3V (150 × 4.6 mm, i.e. 5 μm) column in a gradient mode. Mobile phase consisted of 0.02 M Phosphate buffer adjusted to pH 2.5 using dilute orthophosphoric acid (solvent A) and acetonitrile (solvent B) was set with gradient programming for 18 min and was delivered at 1 ml/min fl ow rate and effl uents are achieved with variable wavelength: Photodiode array detector at 230 nm. Results: The retention times of MET, VOG and GLI were found to be 2.423, 8.191, and 11.708, respectively. The percentage assay of MET, VOG and GLI was found to be 99.92%, 99.32, and 99.72%, respectively. Calibration curves were linear for MET, VOG and GLI at concentration ranges of 200-600 μg/ml, 0.08-0.24 μg/ml, and 0.8-2.4 μg/ml with the regression coeffi cient of 0.999 for all the three drugs and precise with ( % relative standard deviation <2). The limit of detection for MET, VOG and GLI was found to be 0.05 μg/ml, 0.004 μg/ml, 0.002 μg/ml, and limit of quantitation for MET, VOG and GLI was found to be 1.5 μg/ml, 0.012 μg/ml, and 0.006 μg/ml, respectively. Conclusion: The method was validated by determining its linearity, accuracy, precision, system suitability and can be employed for routine quality control analysis as per International Conference o