富电子LMOFs对有机农药的高效荧光检测

High-Efficiency Fluorescent Detection of Organic Pesticides by Electron-Rich LMOFs

摘要:

以三嗪环富电子配体及Zn(Ⅱ)离子构筑的2例类分子筛拓扑结构的发光金属有机框架LMOF-1及LMOF-2作为荧光探针检测有机农药氟乐灵及除草醚。经荧光淬灭实验及密度泛函理论计算证实，LMOF-1及LMOF-2对氟乐灵的检测机理同时包含电荷转移机理及荧光共振能量转移机理；而LMOF-1及LMOF-2对除草醚的检测机理主要为电荷转移机理。LMOF-1对氟乐灵的检测限可低至5.54 μmol，检测效率可达2.959?0.488 μmol-1。

Abstract:

Two zeolite-topology luminescent metal-organic frameworks LMOF-1 and LMOF-2, constructed with the rich electronic triazine ring ligand and Zn(Ⅱ) were employed as fluorescent probes for the detection of carcinogenic organic pesticides trifluralin and nitrofen. The detection mechanism for trifluralin by LMOF-1 and LMOF-2 was assigned to the charge transfer and the fluorescence resonance energy transfer, confirmed by fluorescent quenching experiments and density functional theory calculations. And the detection mechanism for nitrofen by LMOF-1 and LMOF-2 was mainly assigned to the charge transfer. The limit of detection for trifluralin of LMOF-1 could be down to 5.54 μmol•L-1 with the detection efficiency up to 2.959±0.488 L•μmol-1.