Design Of Novel Fluorescence Probes Based On Keto-salicylaldehyde Azine And Their Applications In Biology

As an effective method to visualize the dynamic process of biological activity,fluorescence microscopic imaging technology has made fluorescence probes with high selectivity and stability become the research hotspot in this field.At present,the aggregation-caused quenching(ACQ)and photobleaching commonly occur in most commercial fluorescence probes,which greatly limit their application,but the concept of aggregation-induced emission(AIE)opens up a new field for the development of fluorescence probes.The restriction of intramolecular motion(RIM)has been proposed to explain AIE phenomanen for several years,and the constructions of AIE core materials based on the theory of RIM are also changeable and functionable.In this thesis,a new class of Keto-Salicylaldehyde Azine(KSA)based on RIM and excited-state intramolecular proton transfer(ESIPT)have been developed.The structure-property relationship and luminescence mechanism were studied through a series of structural modification and function optimization,and then the application in the imaging and recognition of specific organelles and microorganisms and their dynamic tracing were expanded.In chapter 1,we systematically summarize and report the KSA probe based on the mechanism of RIM and ESIPT.In chapter 2,based on the structure-property relationship of FAS and DPAS,a series of FAS and DPAS derivatives targeting lipid droplets were developed by introducing groups with different electron effects.What's more,the visualization of tracing lipid droplets and the prevention of Parkinson's disease were investigated.In chapter 3,based on the study of lysosome-targeting AIE-LysoY,three kinds of KSA probes,which are also selective to lysosomes,were synthesized and used as long-term tracing probes for studying lysosome-related disease.In chapter 4,new application of KSA probes in selective recognition of microorganisms are developed,which is reported for the first time that the probe without any modification could specifically identified Gram positive bactria.Through the structure regulation and groups substitution,the mechanism and structure-property relationship of the recognition process were described.