一种ICT型荧光探针的光谱性质与识别机制研究

Spectral Property and Recognition Mechanism of An ICT Fluorescent Probe

以经典的金属离子响应型多羧酸识别基团为结构基础,连接苯乙烯类发色团苯并咪唑荧光基团,在识别基团与荧光基团之间构筑分子内电荷转移(ICT)机制,合成得到一种荧光探针T13;通过荧光光谱、紫外吸收光谱等手段,初步阐明了探针T13对Zn^(2+)、Cu^(2+)、Hg^(2+)的识别机制。结果表明,探针T13对目标物Zn^(2+)、Cu^(2+)、Hg^(2+)均表现出特征响应与稳定荧光性能;识别过程中荧光强度与目标物浓度线性相关,探针与目标物的络合比为1∶1,能够用于水环境中Zn^(2+)、Cu^(2+)、Hg^(2+)的定性检测和定量分析。为探针结构优化、性能筛选与探针-目标离子的生物学成像研究提供了理论基础。

Using the traditional metal ion responsive polycarboxylic acid as a recognition group,and the styrene chromophore benzimidazole as a fluorescent group,we synthesized a fluorescent probe T13 by constructing an intramolecular charge transfer(ICT)mechanism between the recognition group and the fluorescent group.Moreover,we preliminarily clarified the recognition mechanism of the probe T13 for Zn^(2+),Cu^(2+),and Hg^(2+) by means of fluorescence spectrum and UV absorption spectrum.The results show that the probe T13 shows characteristic response and stable fluorescence property to target metal ions Zn^(2+),Cu^(2+),and Hg^(2+).In the recognition process,the fluorescence intensity is linearly correlated with the concentration of the target metal ion,and the complex ratio of the probe T13 to the target metal ion is 1∶1,indicating that the probe T13 can be used for the qualitative detection and quantitative analysis of Zn^(2+),Cu^(2+),and Hg^(2+) in water environment.The study provides a theoretical basis for probe structure modification,properties improvement,and biological imaging of probe-target ions.