Separation-free spectrophotometric platforms for rapid assessment of combined antiplatelet therapy in complex matrices.

To develop simple and rapid UV-spectrophotometric platforms for the simultaneous quantification of a binary mixture containing clopidogrel bisulphate (CPS) and aspirin (ASP) in complex matrices without prior separation. Five mathematical models namely ratio-difference method, mean centering of the ratio spectra, dual wavelength, induced dual wavelength and H-Point Standard Addition method, were utilized for resolving spectral overlap by mathematical processing of ratio and zero-order absorption spectra. Analytes were extracted from tested matrices (whole blood, pharmaceutical formulations and dissolution media buffer) and quantified using the proposed methods. The methods were validated according to ICH guidelines. The developed methods demonstrated limits of detection ranging from 0.67 to 1.09 μg/ml for CPS and 0.49 to 0.71 μg.ml for ASP. All proposed methods allowed for reliable determination of CPS and ASP in complex matrices within reported reference ranges, indicating their potential application for therapeutic drug monitoring and quality control testing.