Jiang Yansong, Chang Wenxin, Li Zhihao, Zhou Xiang, Zhang Panjing, Huang Xuehai, Pan Xinyi, He Zhenda, Wang Yu, Tian Zhongqun
South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China.
State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
JACS Au. 2025 Mar 17;5(4):1875-1883. doi: 10.1021/jacsau.5c00092. eCollection 2025 Apr 28.
Luminescent metal-organic frameworks (MOFs) represent an emerging class of materials for visual analyte detection. In this study, we present a strategy that integrates two synergistic aggregation-induced emissive (AIE) linkers into a MOF, significantly enhancing sensing sensitivity, selectivity, and quantification capabilities for practical applications. The dual AIE linkers simultaneously optimize porosity and amplify emission intensity. The tailored pore structure precisely matches the molecular dimensions of the pesticide 2,6-dichloro-4-nitroaniline (DCN), while Förster resonance energy transfer between the linkers achieves an exceptional fluorescence quantum yield of 92.6%. This design enables ultrasensitive DCN detection in water, with an unprecedented detection limit at the ppb level, along with superior selectivity, rapid response time, high quantification accuracy, recyclability, and strong resistance to interference. A comprehensive investigation using UV-vis, fluorescence, transient absorption, X-ray photoelectron, and Raman spectroscopies, supported by theoretical calculations, attributes the efficient fluorescence quenching to photoinduced energy transfer. Additionally, we demonstrate instant, naked-eye detection of DCN residues on fruit surfaces and contaminated soil by applying MOF solutions and illuminating under UV light. Quantitative analysis of DCN residues on fruits was further achieved using computer vision and a custom script, providing a practical, on-site method for rapid and precise detection of pesticide residues.
发光金属有机框架材料（MOFs）是一类新兴的用于视觉分析物检测的材料。在本研究中，我们提出了一种策略，即将两种协同的聚集诱导发光（AIE）连接体整合到一种MOF中，显著提高了实际应用中的传感灵敏度、选择性和定量能力。双AIE连接体同时优化了孔隙率并增强了发射强度。定制的孔结构与农药2,6-二氯-4-硝基苯胺（DCN）的分子尺寸精确匹配，而连接体之间的Förster共振能量转移实现了92.6%的超高荧光量子产率。这种设计能够在水中实现超灵敏的DCN检测，具有前所未有的ppb级检测限，同时具有卓越的选择性、快速响应时间、高定量精度、可回收性和强抗干扰能力。通过紫外可见光谱、荧光光谱、瞬态吸收光谱、X射线光电子能谱和拉曼光谱进行的全面研究，并辅以理论计算，将有效的荧光猝灭归因于光诱导能量转移。此外，我们通过应用MOF溶液并在紫外光下照射，展示了对水果表面和受污染土壤上DCN残留的即时肉眼检测。利用计算机视觉和自定义脚本进一步实现了对水果上DCN残留的定量分析，提供了一种实用的现场快速精确检测农药残留的方法。
