多功能荧光探针用于次氯酸及微环境检测

Multifunctional Fluorescent Probe for the Detection of Hypochlorite and Microenvironment

次氯酸作为一种活性氧,在免疫系统中起着重要作用,但是过量的次氯酸会对生物体造成严重损伤,因此对次氯酸含量的检测十分有必要.另一方面,生物微环境的稳定是保持细胞正常增殖、分化、代谢和功能活动的重要条件,微环境成分的异常变化可使细胞发生病变.因此,极性和黏度,作为重要的微环境参数,对于其水平的监测是有意义的.在多种次氯酸和微环境检测方法中,荧光分析法由于灵敏度高、选择性好等显著优势受到广泛关注.虽然目前已经有多种探针用于次氯酸、极性或黏度的检测,但它们大多只能实现单一指标的检测.因此,开发一种用于次氯酸及微环境检测的多功能探针十分必要.通过合理的分子设计开发了一种基于香豆素-三苯胺衍生物的新型多功能荧光探针CAT.在设计策略中,将具有聚集诱导发光(AIE)效应的三苯胺衍生物作为供电基团引入D(电子供体)-π-A(电子受体)型分子中,以同时实现基于分子内电荷转移(ICT)效应的极性检测和基于AIE效应的黏度检测.实验证明,探针可以通过最大发射峰处的荧光强度变化实现对极性和黏度水平的监测.此外,选择香豆素衍生物作为次氯酸(HClO)的荧光基团,并以N,N-二甲基硫代甲酸酯作为其识别位点,成功实现了探针对HClO的快速选择性响应,且在中性与碱性环境中稳定.CAT为多功能荧光探针的开发提供了一种很有前景的策略.

As a kind of reactive oxygen species,hypochlorite plays an important role in the immune system.However,excessive hypochlorite causes serious damage to an organism;thus,the hypochlorite content must be detected.The stability of a biological microenvironment is an important requirement for maintaining the normal proliferation,differentiation,metabolism,and functional activities of cells.Abnormal changes in the microenvironment components can cause cell lesions;therefore,important microenvironment parameters such as polarity and viscosity levels must be monitored.Among the various methods for detecting hypochlorite and microenvironment,the fluorescence analysis method has attracted wide attention owing to its high sensitivity and good selectivity.Although many probes have been used to detect hypochlorite,polarity,or viscosity,most can only detect a single indicator;thus,developing a multifunctional probe for hypochlorite and microenvironment detection is necessary.A novel mul tifunctional fluorescent probe,called CAT,which is based on the coumarin-triphenylamine derivative,was developed here using a rational molecular design.In the design strategy,triphenylamine derivatives,which are an aggregation-induced luminescence(AIE)fluorophore,were introduced into the D(electron donor)-π-A(electron acceptor)molecule as the electron donor group.Therefore,CAT could realize polarity and viscosity detection based on the intramolecular charge transfer and AIE effects,respectively.The experiment results show that the probe can monitor the polarity and viscosity levels using fluorescence intensity changes at the maximum emission peak.In addition,coumarin derivatives and N,N-dimethylthioformate were selected as the fluorescent group and recognition site of hypochlorite(HClO),respectively.The probe exhibited good sensitivity and selectivity for HClO and was stable in neutral and alkaline environments.In summary,CAT provides a promising strategy for the development of multifunctional fluorescent probes.