School of Agricultural Engineering and Food Science, Shandong University of Technology, No. 266 Xincun Xilu, Zibo, Shandong 255049, China; Shandong Provincial Engineering Research Center of Vegetable Safety and Quality Traceability, No. 266 Xincun Xilu, Zibo, Shandong 255049, China; Zibo City Key Laboratory of Agricultural Product Safety Traceability, No. 266 Xincun Xilu, Zibo, Shandong 255049, China.
School of Agricultural Engineering and Food Science, Shandong University of Technology, No. 266 Xincun Xilu, Zibo, Shandong 255049, China; Shandong Provincial Engineering Research Center of Vegetable Safety and Quality Traceability, No. 266 Xincun Xilu, Zibo, Shandong 255049, China; Zibo City Key Laboratory of Agricultural Product Safety Traceability, No. 266 Xincun Xilu, Zibo, Shandong 255049, China.
J Hazard Mater. 2022 Oct 15;440:129707. doi: 10.1016/j.jhazmat.2022.129707. Epub 2022 Aug 1.
For the visual detection of four organophosphorus pesticides (OPs), a colorimetric aptasensor was developed based on aptamer-mediated bimetallic metal-organic frameworks (MOFs) nano-polymers. Fe-Co magnetic nanoparticles (MNPs) and Fe-N-C nanozymes were prepared based on pyrolytic reaction, and were labeled with broad spectrum aptamers and complementary chains of organophosphorus pesticides respectively. The hybridization of aptamers and complementary chains led to the formation of nano-polymers. In the presence of target pesticides, they competed with complementary chains for aptamers on Fe-Co MNPs, resulting in a large number of Fe-N-C nanozymes signal labels being released into the supernatant. Fe-N-C nanozymes showed similar activity to peroxidase and catalyzed the 3,3',5,5'-tetramethylbenzidine-hydrogen peroxide (TMB-HO) color system to turn the solution blue-green under mild conditions. The magnetic probes had good selectivity and sensitivity, and were easily separated by magnetic absorption. The sensor functioned well under optimal conditions, demonstrating good stability and specificity for four pesticides: phorate, profenofos, isocarbophos and omethoate, and the detection limits of four pesticides were as low as 0.16 ng/mL, 0.16 ng/mL, 0.03 ng/mL and 1.6 ng/mL respectively, and the recovery rate of OPs residue in vegetable samples was satisfactory. The work described here provided a simple, rapid and sensitive way to construct a biosensor.
为了实现对四种有机磷农药（OPs）的可视化检测，开发了一种基于适配体介导的双金属金属有机骨架（MOFs）纳米聚合物的比色适体传感器。基于热解反应制备了 Fe-Co 磁性纳米颗粒（MNPs）和 Fe-N-C 纳米酶，并分别用广谱适配体和 OPs 的互补链进行标记。适配体和互补链的杂交导致纳米聚合物的形成。在存在目标农药的情况下，它们与互补链竞争 Fe-Co MNPs 上的适配体，导致大量 Fe-N-C 纳米酶信号标签被释放到上清液中。Fe-N-C 纳米酶表现出类似过氧化物酶的活性，并在温和条件下催化 3,3',5,5'-四甲基联苯胺-过氧化氢（TMB-HO）显色体系，使溶液变为蓝绿色。磁探针具有良好的选择性和灵敏度，并可通过磁性吸收轻松分离。该传感器在最佳条件下运行良好，对四种农药（甲拌磷、丙溴磷、异稻瘟净和氧乐果）表现出良好的稳定性和特异性，四种农药的检测限分别低至 0.16ng/mL、0.16ng/mL、0.03ng/mL 和 1.6ng/mL，蔬菜样品中 OPs 残留的回收率令人满意。这里描述的工作为构建生物传感器提供了一种简单、快速和灵敏的方法。
