DNA-Templated Ag Nanocluster/CdSe@ZnS Quantum Dot-Based Platform for Colorimetric and Fluorescence Detection of Organophosphorus Pesticide

作者：Xiaoxia Kang, Jige Yuan, Xijuan Gu, Xiaoyan Li, Tao Wen, Miao He, Yue He, Xiaoxiao Yang, Yuechen Li, Conglin Guo, Haiwei Ji, Yuling Qin, Li Wu · 发表于：ACS Applied Nano Materials · 年份：2025 · DOI：10.1021/acsanm.4c06928 · 被引用次数：10 · 研究领域：Nanocluster Synthesis and Applications、Advanced biosensing and bioanalysis techniques、Advanced Nanomaterials in Catalysis

The agriculture and environmental industries have employed organophosphorus pesticides (OPs) chemicals as insecticides extensively in previous decades, leading to persistent life-threatening issues. Therefore, developing a platform for the efficient identification of OPs is significant for environmental protection and human health. In this study, a strategy for the colorimetric and fluorescence detection of OPs by combining quantum dots (QDs) with DNA-templated silver nanoclusters (DNA-AgNCs) was proposed. Technically, the fluorescence of DNA-AgNCs will be enhanced once guanine (G)-rich sequences get close to the DNA-AgNCs to form hybrid complexes DNA-AgNCs/G, while quenching of fluorescence can be attributed to the hydrolysate (thiocholine) of acetylthiocholine (ATch) that was caused by acetylcholinesterase (AchE). Based on the fact that OPs can irreversibly inhibit the catalytic activity of AchE and slow down the fluorescence quenching of DNA-AgNCs/G, thus, OPs detection can be achieved by evaluating the fluorescence intensity of DNA-AgNCs/G. Additionally, a dual-mode detection system (colorimetric and fluorescent) is achieved through an ion-exchange reaction between QDs and DNA-AgNCs/G. The concentration of OPs is quantified by monitoring fluorescence changes in the QDs and poly(9,9-dioctylfluorene) (PFO) polymer dots (Pdots) system, with PFO Pdots serving as a stable internal reference. Using trichlorfon as a model, the limit of detection (LOD) was 2.55 pg/mL, while an ex...