A novel nopinone-based fluorescent probe for sensitive detection of pesticide parathionmethyl in soil and its applications in biological imaging

Abstract

The overapplication of chemical pesticides will cause heavy pollution in water, soil, and foodstuff, and cause irreversible damage to the ecological environment and human health. Therefore, it is imperative to develop a highly sensitive and reliable tool for detecting pesticide residues in the environment. In this work, a novel nopinone-based fluorescent probe THIPOCP for the detection of parathion−methyl was constructed from BchE inhibition principles. The ester bond in THIPOCP was hydrolyzed by BchE, leading to the release of the fluorophore THIPOH and a significant enhancement of the fluorescence signal at 547 nm. However, parathion-methyl could inhibit BchE activity significantly and resulted in fluorescence quenching at 547 nm. Probe THIPOCP was effectively used to detect BchE and parathionmethyl, and the detection limits were as low as 8.56 U/L and 0.79 μg/mL, respectively. A portable smartphone-based analysis platform for quantitative and qualitative analysis of parathionmethyl in soil was developed from probe THIPOCP. This probe can also be used to detect butyrylcholinesterase (BchE) and parathionmethyl in living cells and zebrafish, providing a new tool for monitoring BchE and parathionmethyl in living systems, which is helpful for protecting human life and health. Therefore, the probe THIP-OCP is regarded as a promising tool for monitoring environmental safety and biological health systems.