Development and Validation of Stability Indicating UPLC method of Memantine and Donepezil Fixed Dosage Form Combination in Marketed Dosage form

A simple, Accurate, precise method was developed for the simultaneous estimation of the Memantine and Donepezil in Tablet dosage form. Chromatogram was run through X Bridge 100 x 2.1mm 3.5µm. Mobile phase containing Buffer 0.1% OPA: Acetonitrile taken in the ratio 60:40 was pumped through column at a flow rate of 0.2 ml/min. Buffer used in this method was 0.1% OPA buffer(4.5Ph). Temperature was maintained at 30°C. Optimized wavelength selected was 240.0 nm. Retention time of Memantine and Donepezil were found to be 0.901 min and 1.159 %RSD of the Memantine and Donepezil were and found to be 0.8 and 0.6 respectively. %Recovery was obtained as 100.25%& 99.98% for Memantine and Donepezil respectively. LOD, LOQ values obtained from regression equations of Memantine and Donepezil were 0.03, 0.08 and 0.08, 0.23 respectively. Regression equation of Memantine is y = 11481x + 1897.6, and y = 10726x + 1008.5., of Donepezil. Retention times were decreased and that run time was decreased, so the method developed was simple and economical that can be adopted in regular Quality control test in Industries.