Analytical Method Development and Validation of First Order Derivative Spectrophotometric Method for Simultaneous Estimation of Amiloride and Torsemide in their Combined Pharmaceutical Dosage Form

UV Spectrophotometric method has been developed for simultaneous estimation of Amiloride (AML) and Torsemide (TSM) in bulk drug and in their combined dosage form by first order derivative. This method utilizes methanol as a solvent and λmax of Amiloride and Torsemide selected for analysis was found to be 248 nm(at ZCP of TSM) and 308 nm (at ZCP of AML) respectively. Linearity was observed in the concentration range of 4-14μg/ml for AML (r2 = 0.999) and 4-20 μg/ml for TSM (r2 = 0.998). The accuracy and precision were determined and found to comply with ICH guidelines. This method showed good reproducibility and recovery with % RSD in the desired range. The proposed methods can be successfully applied for the routine analysis of both the drugs. This method was simple, rapid, accurate, and sensitive.