A Validated Stability-indicating Hplc Assay Method for Determination of Fesoterodine Fumarate

A novel stability indicating reverse-phase high performance liquid chromatographic method has been developed for quantitative determination of Fesoterodine Fumarate, new antimuscarinic agent for the treatment of overactive bladder. The chromatographic separation was achieved using an Inertsil ODS-3V (150mm × 4.6mm × 5μm) in isocratic mode employing Buffer (1.15g of Ammonium dihydrogen orthophosphate, 2.0mL Triethylamine in 1000mL of water. Adjust pH of the solution to 3.0±0.05 with Orthophosphoric acid solution) and Methanol in the ratio of 42:58(v/v) with a 1.0 mL/min flow rate was chosen. Detector wavelength monitored at 210nm. The column temperature was maintained at 30°C.Fesoterodine Fumarate was exposed to thermal, photolytic, acid, base and oxidative stress conditions. Considerable degradation of the drug substance was found to occur under acid, base and oxidative stress conditions. Peak homogeneity data of Fesoterodine Fumarate obtained by photodiode array (PDA) detection demonstrated the specificity of the method in the presence of degradants. The degradation products were well resolved from main peak of Fesoterodine Fumarate thus proved the stability, indicating power of the method. The developed method was validated as per International Conference on Harmonization (ICH) guidelines with respect to specificity, precision, linearity, accuracy and robustness.Regression analysis showed correlation coefficient value greater than 0.999. Accuracy of the method was established based on the recovery obtained between 96.9% and 101.5% for Fesoterodine Fumarate.