College of Chemistry and Materials, Fujian Normal University, Fuzhou 350007, PR China.
College of Chemistry and Materials, Fujian Normal University, Fuzhou 350007, PR China; Fujian Key Laboratory of Polymer Materials, Fuzhou 350007, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2021 Mar 5;248:119191. doi: 10.1016/j.saa.2020.119191. Epub 2020 Nov 14.
Previously reported fluorescent sensors for Th experienced emission quenching or generated false positive signal upon aggregate formation in aqueous media. Herein, a simple and novel thorium sensor (CDB-BA) based on cyanodistyrene structure was designed and synthesized, which integrated the highly emitting characteristic of AIE effect and off-on response of PET modulation for the first time to construct the "turn-on" fluorescent probe for Th. Besides excellent selectivity, CDB-BA exhibited remarkable fluorescent enhancement which was linearly related to the concentration of Th in the range of 0.25-8 μM. The detection limit was attained 0.074 μM, which was lower than that of most previously reported sensors. The mechanism of tris-chelate complex of CDB-BA with Th was confirmed by mass spectra, IR spectra and DFT calculation. The excellent Th sensing ability of CDB-BA was successfully applied to detecting Th on TLC plates, in real water samples and living-cell imaging. This work suggested that the combination of AIE and PET photophysical mechanism could offer the merits of minimized background and enhanced signal fidelity to develop novel "turn-on" fluorescent probe in complicated aqueous environment and biological research.
先前报道的用于检测钍的荧光传感器在水相介质中聚集形成时会经历荧光猝灭或产生假阳性信号。本文设计并合成了一种基于氰基二苯乙烯结构的简单新颖的钍传感器（CDB-BA），它首次集成了 AIE 效应的高发射特性和 PET 调制的开-关响应，构建了用于检测 Th 的“开”式荧光探针。除了出色的选择性外，CDB-BA 还表现出显著的荧光增强，其与 Th 的浓度在 0.25-8 μM 的范围内呈线性关系。检测限达到 0.074 μM，低于大多数先前报道的传感器。通过质谱、红外光谱和 DFT 计算证实了 CDB-BA 与 Th 形成的三螯合配合物的机理。CDB-BA 优异的 Th 传感能力成功应用于 TLC 板上、实际水样和活细胞成像中的 Th 检测。这项工作表明，AIE 和 PET 光物理机制的结合可以提供最小化背景和增强信号保真度的优点，从而在复杂的水相环境和生物研究中开发新型“开”式荧光探针。
