Eco-friendly Spectrophotometric Methods for Assessment of Alfuzosin and Solifenacin in their new Pharmaceutical Formulation; Green Profile Evaluation via Eco-scale and GAPI Tools

Background: Alfuzosin is recently co-formulated with solifenacin for relieving two coincident urological diseases, namely; benign prostate hyperplasia and overactive bladder. Objective: Herein, green, simple and rapid spectrophotometric methods were firstly developed for simultaneous determination of the two cited drugs in their co-formulated pharmaceutical capsule. Methods: Alfuzosin, which is the major component in the dosage form, was directly assayed at its extended wavelength at 330.0 nm. The challenging spectrum of the minor component, solifenacin, was resolved by five spectrophotometric methods, namely; Dual Wavelength (DW) at 210.0 & 230.0 nm, first derivative (¹D) at 222.0 nm, Ratio Difference (RD) at 217.0 - 271.0 nm , derivative ratio (¹DD) at 223.0 and mean centering of ratio spectra (MC) at 217.0 nm. Results: The proposed methods were successfully validated as per ICH guidelines. Alfuzosin showed linearity over the range of 4.0 - 70.0 μg/mL, while that of solifenacin were 4.0 - 50.0 μg/mL for DW, 2.0 - 70.0 μg/mL for ¹D and RD methods, 1.0 - 70.0 μg/mL for ¹DD and 4.0 - 70.0 μg/mL for MC method. Statistical comparison with their official ones showed no noticeable differences. The methods showed good applicability for assaying drugs in their newly combination. Besides the eco-scale, the greenness profile of the methods was assessed and compared with the reported spectrophotometric one via the newest metric tool; Green Analytical Procedure Index (GAPI). Conclusion: The proposed methods are superior in not only being smart, accurate, selective, robust and time-saving, but also in using distilled water as an eco-friendly and cheap solvent.