有机染料聚集在光化学传感中的应用

Photochemical Sensing Based on the Aggregation of Organic Dyes

有机染料在可见-近红外光区具有较高的摩尔消光系数和良好的荧光发光性能,因而常被用于光谱化学传感中。通常有机染料分子含有较大的π体系,在溶液中易于通过分子间弱相互作用(氢键、卤键、亲疏水作用、π-π堆积作用、范德华力等)聚集形成具有特定结构的组装体,聚集过程往往伴有明显的颜色或光谱变化。若向染料分子中引入特定的官能团,与分析物结合诱导染料聚集/解聚产生明显的光谱变化,可用于对分析物的识别。聚集体可同时提供多个结合位点,并具有组装单元之间可调控的空间取向、较高的传感结合基团局部浓度。因此基于聚集过程的光化学传感表现出优越的传感灵敏度和选择性。本文结合本课题组近年来的研究工作综述了有机染料聚集在光化学传感中的应用,分别从诱导聚集、诱导解聚以及聚集重组三个方面展开讨论,并展望了此类荧光传感体系未来的研究与发展方向。

Organic dyes possess high molar extinction coefficient and good fluorescence emission performance in visible and NIR region,thus they are often used in spectrochemical sensing.Generally,organic dyes usually contain a largeπsystem,and are easy to form assemblies with specific structures through weak intermolecular interactions(such as,hydrogen bonds,halogen bonds,hydrophobic interactions,π-πstacking interactions,van der Waals forces.)in solution.The aggregation process is often accompanied by obvious color or spectral changes.If a specific functional group is introduced into a dye molecule,binding with an analyte induces the aggregation or disaggregation to produce obvious spectral changes,which can be used for the detection of the analyte.Supramolecular aggregates can provide multiple binding sites simultaneously,and have adjustable spatial orientation between assembly units and higher local concentration of sensing binding groups.Therefore,photochemical sensing based on aggregation process shows superior sensing sensitivity and selectivity.In this review,the application of the aggregation of organic dyes in photochemical sensing is reviewed based on our own research work in recent years.Three aspects of induced aggregation,disaggregation and aggregation rearrangement are discussed respectively,and the future research and development direction of such fluorescent sensing systems are also prospected.