Ammonia (NH3) and hydrazine (N2H4) present potential risks to human health, food and environmental safety. A sustainable flavonol-based probe, quercetin pentaacetate (QPA, weak blue emission 417 nm), was fabricated for dual-ratiometric fluorescent sensing and visual differentiating NH3 and N2H4. Excited state intramolecular proton transfer-on products with green (487 nm) and yellow (543 nm) emissions occurred as meeting with NH3 and N2H4, respectively, for their different nucleophilicities. Such a promising response offered a great opportunity of QPA to discriminatively detect NH3 and N2H4 with large Stokes shifts (>122 nm), high sensitivity (limit of detection: 35.4 μM and 0.70 ppm for NH3 solution and gas; 0.26 μM for N2H4 solution), excellent accuracy (spiked recoveries from 98.6 % to 105 %), and superior selectivity. Importantly, QPA was utilized for monitoring NH3 vapor in fish spoilage procedures and detecting N2H4 in water samples for food and environmental safety evaluation.
Keywords: Ammonia; Fluorescent differentiation; Hydrazine; Quercetin; Ratiometric detection.
Copyright © 2023 Elsevier Ltd. All rights reserved.