Synthesis Of Tetraphenylene Fluorescent Probes And Their Application To The Detection Of CYP2J2 Enzyme And Mercury Ion

Cytochrome P450 2J2（CYP2J2）is a key enzyme in the oxidative metabolism of a variety of biological and endogenous compounds involved in a variety of human physiological and pathological processes.CYP2J2 enzyme is involved in the metabolism of endogenous compounds in the body and catalyze the production of oncogenic chemicals.Therefore,CYP2J2 enzyme can be used as diagnostic biomarkers and potential targets for cancer development and progression.Divalent mercury ion(Hg²⁺)is a common,bioaccumulative and highly toxic contaminant in the environment.Hg²⁺contamination accumulates through the food chain and poses a widespread and serious threat to living organisms,causing neurological and renal effects.The presence of both of these substances in the human body is harmful,therefore,it is necessary to develop a means by which these substances can be detected quickly and easily.Fluorescence spectroscopy allows not only specific detection and rapid analysis of target substances in real-time,but also in situ and visual detection and tracer imaging in cells and even living tissues.Given the hazardous nature of CYP2J2 enzyme and Hg²⁺in physiological processes and the environment,it is important to acquire fluorescent probes for the detection of CYP2J2 enzyme and Hg²⁺.In this thesis,two fluorescent probes for aggregation-induced emission（AIE）of tetraphenylene were designed and synthesized to achieve fluorescence detection of CYP2J2enzyme and Hg²⁺,respectively,as follows:（1）A fluorescence-enhanced fluorescent probe（TPE-Bn）based on the AIE effect was designed and synthesized using a tetraphenylethylene derivative,TPE-Br,as a fluorophore.The probe TPE-Bn uses methoxy as the reaction site for the detection of CYP2J2 enzyme,and has a high selectivity and sensitivity for the detection of CYP2J2 enzyme as well as a low lower limit of detection（1.09 n M）in the range of 0～20 n M with a large Stokes shift.In addition,the probe exhibited excellent cytocompatibility and low cytotoxicity for visualizing CYP2J2 enzyme produced endogenously in human hepatocellular carcinoma cells Hep G2 and human non-small cell lung cancer cells A549.The tissue imaging results showed that the probe has good penetration ability,providing potential applications for its pathological studies in humans.（2）Based on the catalytic reaction of metallic palladium,a“Turn-off”type fluorescent probe（TPE-DAMN）for the detection of Hg²⁺in aqueous solution was designed and synthesized using the tetraphenylethylene derivative TPE-Br as the fluorophore.The TPE-DAMN fluorescent probe also has AIE properties and shows excellent detection performance for Hg²⁺,with highly selective quenching of Hg²⁺in the range of 0～40μM,as well as the excellent anti-interference ability and low lower detection limit（0.45μM）,which can be used for actual water sample detection.In addition,the probe TPE-DAMN exhibits excellent cell permeability and low cytotoxicity and can detect Hg²⁺in Hep G2 cells.In summary,this dissertation was completed with the synthesis of two probes and the study of fluorescence detection aspects and bioimaging aspects of two different substances to be measured.