综述聚集诱导发光(aggregation—induced emission,AIE)现象的发现、机理及其在生物/化学探针应用研究方面的进展.指出传统荧光分子溶液浓度过高或分子发生聚集后,往往发生分子荧光淬灭,而AIE现象刚好与之相反,分子发生聚集后荧光会增强数倍或数百倍.AIE现象的本质是分子聚集使分子间相互作用增强,限制了分子内基团的自由旋转,抑制了其非辐射能量的转移,使分子荧光增强.生物分子或待测化学物质可以通过疏溶剂作用、静电作用或配位作用诱导AIE分子发生聚集,使分子荧光显著增强,根据这一“光开关效应”可以构筑用于蛋白、DNA、金属离子以及有害物质检测的生物/化学传感器.该类新型传感器操作简单便捷,与传统的检测方法相比,在检测灵敏性和选择性方面具有极大的优势.
The finding of aggregation-induced emission (AIE) and development of AIE-based application in bio/chemosensors is reviewed. The conventional chromophoric molecules are usually quenched because of molecular aggregation. However, the AIE molecules are non-emissive in solution, but their luminescence is significantly enhanced when they aggregate or exist in solid state. The essence of AIE is the restriction of intramolecular rotation and enhancement of intermolecular interaction, which blocks the non-emissive energy transfer and therefore leads to an increase of luminescence. Biomolecules or chemical analyte can induce AIE molecules to aggregate with a significant increase of luminescence. This "light-switch" mechanism can be employed to develop bio/chemosensors for protein, DNA and chemical analyte detection. The AIE based bio/chemosensors are easy to operate. They also have the advantages of high sensitivity and selectivity compared with conventional detection methods.