Enzyme-targeted near-infrared fluorescent probe for organophosphorus pesticide residue detection.

Abstract

Pesticide residues significantly affect food safety and harmhuman health. In this work, a series of near-infrared fluorescent probes were designed and developed by acylating the hydroxyl group of the hemicyanine skeleton with aquenching moiety for monitoring the presence of organophosphorus pesticides in food and live cells. The carboxylic ester bond on the probe was hydrolyzed catalyticallyin the presence of carboxylesterase and thereby the fluorophore was releasedwith near-infrared emission. Notably, the proposed probe 1 exhibited excellent sensitivity against organophosphorus based on the carboxylesterase inhibition mechanism and the detection limit for isocarbophos achieved 0.1734μg/L in the fresh vegetable sample. More importantly, probe 1 allowed for situ visualization of organophosphorus in live cells and bacteria, meaning great potential for tracking the organophosphorus in biological systems. Consequently, this study presents a promising strategy for tracking pesticide residues in food and biological systems.