Novel eco-friendly spectrophotometric determination of potential combination silodosin and darifenacin hydrobromide in bulk and pharmaceutical formulations

Abstract

Silodosin and darifenacin hydrobromide have lately been administered to males with overactive bladder for the management of benign prostatic hyperplasia. The present work details the development and validation of spectrophotometric methods that demonstrate reliability, accuracy, and selectivity for quantifying two medications in bulk and pharmaceutical formulations. Both drugs are quantified from the recorded spectra using different mathematical manipulations. Direct measurement of silodosin concentration was performed at a wavelength of 328.8 nm. The methods for determining darifenacin include Method I, which employs fourier self-deconvolution; Method II, which utilizes ratio difference analysis; and Method III, which applies first derivative ratio. The procedure parameters were validated following ICH recommendations. The methodologies included the direct quantification of silodosin within the range of 10-45 µg/mL with LOD and LOQ of 0.942 and 2.857 µg/mL respectively, as well as Fourier self-deconvolution, ratio difference, and first derivative ratio spectrophotometric techniques for the assessment of darifenacin hydrobromide within the range of 5-70 µg/mL with LOD and LOQ for each method of (0.484, 1.468 µg/mL), (1.353, 4.100 µg/mL), (0.794, 2.408 µg/mL), respectively. Recovery studies validated the accuracy of the methods in pharmaceutical formulations, with an average recovery of 100.37% for silodosin (direct method) and 100.96%, 99.87%, and 100.69% for darifenacin hydrobromide using fourier self-deconvolution, Ratio difference, and first derivative ratio methods, respectively. The procedures demonstrate a high level of environmental sustainability, as evidenced by Analytical GREEnness calculator (a comprehensive, flexible, and straightforward assessment approach that provides an easily interpretable and informative result for evaluating greenness), Modified Green Analytical Procedure Index (which merges the advantages of the visual impact of Green Analytical Procedure Index with the precise total score of the analytical Eco-Scale and provides an overall assessment of the method greenness by calculating a total score), spider chart, green solvents selection tool (spider chart and green solvent selection tools were applied to select and evaluate solvents used during the experiment) and Blue applicability grade index (evaluating the practicality of an analytical techniques).