【摘要】 有机磷农药（Organophosphorus pesticides, OPs）作为全球农业广泛使用的杀虫剂，因其高环境持久性和显著生物毒性，其残留物对生态环境和人体健康构成严重威胁。目前，基于乙酰胆碱酯酶（Acetylcholinesterase,AChE）抑制作用的比色传感检测方法因其操作简便、特异性强等优势，已成为检测OPs的重要手段，其中纳米酶作为常用检测试剂发挥了关键作用。然而，传统纳米酶催化效率的固有局限性严重制约了该检测方法灵敏度的进一步提升。本研究采用溶剂热法一步合成了金纳米颗粒（Au NPs）负载的多金属氧酸盐纳米带（Au-POM），在酸性环境下可以催化H₂O₂分解，表现出典型的类过氧化物酶活性。基于此，构建了AChE、胆碱氧化酶（ChOx）和Au-POM三酶级联催化体系，通过AChE特异性催化氯化乙酰胆碱（ACh）水解为胆碱，随后ChOx介导胆碱氧化产生H₂O₂副产物。在此过程中，具有类过氧化物酶活性的Au-POM催化H₂O₂分解产生活性氧，氧化显色底物3,3′,5,5′-四甲基联苯胺（TMB）生成氧化态产物（oxTMB），在625 nm处具有特征吸收，同时溶液颜色变为蓝色。OPs类杀虫剂灭线磷（EP）存在时，间接抑制TMB氧化，溶液颜色及625 nm处吸光度随EP浓度呈现梯度变化，基于此建立了三酶级联催化体系检测OPs的方法。本方法具有操作简单、检出限低（1.05μmol/L）和线性范围宽（20～180μmol/L）等优点，并具有良好的选择性。本方法被成功应用于湖水和香菜中EP浓度的比色分析，为环境与食品中OPs的监测提供了可靠的技术平台。更多还原

【Abstract】 Organophosphorus pesticides（OPs） are widely used in global agriculture, and pose a serious threat to ecological environment and human health due to their high environmental persistence and biological toxicity.Colorimetric sensing strategies based on the inhibition of acetylcholinesterase（AChE） have become an important method for detecting OPs because of their simplicity and high specificity. However, the sensitivity is limited by the insufficient catalytic efficiency of traditional nanozymes. In this study, a one-step solvothermal method was used to synthesize polyoxometalate nanoribbons（POM） loaded with gold nanoparticles（Au NPs）, named Au-POM.Experimental results showed that Au-POM could catalyze the decomposition of H₂O₂ in an acidic environment（pH 4.0）, demonstrating typical peroxidase-like activity. Based on this, an AChE, choline oxidase（ChOx） and AuPOM nano enzyme cascade catalytic system was constructed. In this system, AChE specifically catalyzed the hydrolysis of acetylcholine（ACh） to choline, and then ChOx mediated the oxidation of choline to produce H₂O₂.During this process, Au-POM acted as a peroxidase-like enzyme to catalyze the decomposition of H₂O₂ to generate reactive oxygen species, triggering a specific oxidation reaction of the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine（TMB） into oxidized form. When the OP pesticide ethoprophos（EP） was present, it inhibited the activity of AChE and blocked the generation of ACh and H₂O₂, indirectly inhibiting the oxidation of TMB. The color and absorbance of the solution changed in a concentration-dependent manner. The detection limit of this method for EP was 1.05μmol/L, and the linear response range was 20–180μmol/L（R²=0.998）. This method was applied to detection of environmental water samples and coriander samples with satisfactory results, providing a reliable technical platform for monitoring of OPs in environment and food.更多还原