Green spectrofluorimetric quantification of aspirin, olmesartan, and metoprolol in spiked human plasma

Low dose aspirin is routinely taken with antihypertensive drugs such as olmesartan and metoprolol to avoid the cardiovascular and renal outcomes associated with high blood pressure. The first spectrofluorimetric method for quantifying aspirin, olmesartan, and metoprolol in spiked human plasma is described here. The emission/excitation wavelengths of Aspirin, olmesartan, and metoprolol were 404 nm/290 nm, 372 nm/250 nm, and 302 nm/230 nm, respectively. The native fluorescence spectra of metoprolol do not overlap with those of aspirin or olmesartan, although the spectra of aspirin and olmesartan overlap. As a result, metoprolol could be measured directly in a mixture at 302 nm following excitation at 230 nm. Using synchronous fluorescence spectrometry at Δλ = 110 allowed for the determination of olmesartan at 364 nm with no interference from aspirin and metoprolol. Coupling the synchronous fluorescence spectrometry with second-order derivative allowed for the determination of aspirin at 426 nm with no interference from olmesartan and metoprolol. The suggested approach has been validated using ICH M10 criteria for bioanalytical method validation and was effectively utilized for quantification of tested medications in human plasma with reasonable accuracy and precision findings. Furthermore, using two greenness metrics, the Green Analytical Procedure Index and the Analytical GREEnness, the suggested method obtained a high greenness score.