Organophosphorus pesticides (OPs) are widely used in agricultural production, but their residues could cause pollution to the environment and living organisms. In this paper, a simple dual-readout method for OPs detection was proposed based on ChOx single enzyme inhibition. Firstly, ChOx can catalyze the production of H₂O₂ from choline chloride (Ch-Cl). Bifunctional iron-doped carbon dots (Fe-CDs) with good peroxidase-like activity and superior fluorescence properties can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB) by H₂O₂ formed, and oxTMB could quench the fluorescence of Fe-CDs. In light of the fact that OPs exhibited activity in inhibiting ChOx, less H₂O₂ and the decreasing oxTMB led to a result that the fluorescence of the system recovered and the solution became lighter in blue color. Moreover, the process of ChOx inhibition by OPs was analyzed by molecular docking technique and it was found that OPs interact with key amino acid residues catalyzed by ChOx (Asn510, His466, Ser101, His351, Phe357, Trp331, Glu312). Finally, a dual-mode (colorimetry and fluorescence) sensor was created for the detection of OPs with the detection limit of 6 ng/L, and was successfully used in the quantitative determination of OPs in actual samples with satisfactory results.

有机磷农药(OPs)在农业生产中广泛使用，但其残留会对环境和生物体造成污染。本文提出了一种基于ChOx单酶抑制的简单双读数OPs检测方法。首先，ChOx可以催化氯化胆碱(Ch-Cl)生产H ₂ O _{2 。}双功能铁掺杂碳点（Fe-CD）具有良好的类过氧化物酶活性和优异的荧光性能，可以催化H 2 将3,3',5,5'-四甲基联苯胺（TMB）氧化为蓝色氧化TMB（oxTMB_） O ₂形成，oxTMB可以猝灭Fe-CDs的荧光。鉴于OPs表现出抑制ChOx的活性，减少H ₂ O ₂和减少oxTMB导致体系荧光恢复，溶液颜色变浅蓝色。此外，通过分子对接技术分析OPs抑制ChOx的过程，发现OPs与ChOx催化的关键氨基酸残基（Asn510、His466、Ser101、His351、Phe357、Trp331、Glu312）相互作用。最后研制了一种检测限为6 ng/L的双模式（比色法和荧光法）传感器用于OPs的检测，并成功用于实际样品中OPs的定量测定，得到了满意的结果。