In this work, a novel electrochemiluminescence (ECL) aptasensor was structured for the detection of four organophosphorus pesticides (OPs). Firstly, multi-walled carbon nanotubes (MWCNTs) were used to create a favorable loading interface for the fixation of tris (2, 2’-bipyridyl) ruthenium (II) (Ru(bpy)₃²⁺). At the same time, copper (core)-gold (shell) bimetallic nanoparticles (Cu@Au NPs) were synthesized in the aqueous phase for the sensor construction. Gold nanoparticles (Au NPs) could promote the electrochemiluminescence intensity of Ru(bpy)₃²⁺ with high efficiency by catalyzing the oxidation process of tri-n-propylamine (TPrA). Compared with the Au NPs, Cu@Au NPs increased the solid loading of Au NPs by virtue of the large specific surface area of copper nanoparticles (Cu NPs), which could further improve the sensitivity of aptasensor. When OPs were added, the ECL intensity was significantly reduced, and the concentration of OPs could be detected through the ECL intensity. Under the optimum conditions, the aptasensor had a wider dynamic range and ultra-low detection limit for the detection of four pesticides: profenofos, isocarbophos, phorate, and omethoate, and their detection limits were 3×10^-4 ng/mL, 3×10^-4 ng/mL, 3×10^-3 ng/mL, and 3×10^-2 ng/mL respectively (S/N = 3). The aptasensor had the merits of good stability, reproducibility, and specificity, and had a favourable recovery rate in detecting OPs residues in vegetables. This work provided an effective method for the construction of a simple, rapid, and sensitive biosensor.

在这项工作中，构建了一种新型电化学发光 (ECL) 适体传感器，用于检测四种有机磷农药 (OP)。首先，使用多壁碳纳米管 (MWCNT) 为固定三 (2, 2'-联吡啶基) 钌 (II) (Ru(bpy) ₃ ²⁺ )创造了有利的负载界面。同时，在水相中合成了铜（核）-金（壳）双金属纳米粒子（Cu@Au NPs）用于传感器结构。金纳米粒子 (Au NPs) 可以提高 Ru(bpy) ₃ ²⁺的电化学发光强度通过催化三正丙胺 (TPrA) 的氧化过程高效地进行。与Au NPs相比，Cu@Au NPs由于铜纳米颗粒（Cu NPs）的大比表面积增加了Au NPs的固载量，这可以进一步提高适体传感器的灵敏度。添加OPs后，ECL强度显着降低，可以通过ECL强度检测OPs的浓度。在最佳条件下，适体传感器对丙磺磷、异卡波磷、甲拌磷和氧化乐果四种农药的检测具有更宽的动态范围和超低检出限，其检出限分别为3×10 ^-4 ng/mL、3× 10 ^-4 ng/mL、3×10 ^-3 ng/mL 和 3×10 ^-2分别为 ng/mL (S/N = 3)。该适体传感器具有良好的稳定性、重现性和特异性等优点，在蔬菜中OPs残留检测中具有良好的回收率。该工作为构建简单、快速、灵敏的生物传感器提供了一种有效的方法。