Novel and Ultra-sensitive Harnessing of Native Fluorescence and Bio-Inspired N, S-CQDs: A Greener Path to Pharmaceutical and Biological Analysis of Moexipril with Enhanced Sustainability Profiles

Abstract

Monitoring the level of Moexipril is crucial for hypertensive patients, therefore two environmentally friendly, rapid and selective analytical techniques have been established for its sensitive measurement. First method relies on direct measurement of its native fluorescence at λ_ex 282 nm / λ_em 315 nm. The second method is based on the efficient and quantitative enhancement of N, S-CQDs fluorescence intensity by Moexipril in the presence of 1% Tween. The remarkably fluorescent N and S-CQDs were developed via 8 minutes microwave-aided one-pot synthesis using promising, cheap and widely available precursors (Arugula leaves) for the first time. The sensor is characterized by excellent doping efficiency (N, 13.01% and S, 12.39%), narrow particle size distribution (2.7±0.6 nm), reproducibility and good fluorescence at λ_ex 320nm / λ_em 430 nm with 68.5% quantum yield. Also, the designed probe selectivity was verified in presence of possible co-existing excipients, various metal ions and co-administered drugs that grants the practical applicability of N, S-CQDs as an environmental probe. Additionally, both methods showed excellent linearity (r = 0.9999) within the specified concentrations range (0.02-0.6 and 0.004-0.7 µg/mL for method I and II, respectively) and they were implemented for the analysis of Moexipril in pharmaceutical tablets and biological fluids, yielding high recovery percentages. The proposed procedures were fully validated in compliance with the ICH Guidelines. Moreover, the greenness, blueness and whiteness profiles of developed methods were evaluated for accomplishment of a complete ecological profile of the designed fluorimetric methodologies and the excellent obtained results confirmed their excellent eco friendless, good applicability and sustainability.