Preparation And Detection Application Of Triphenylamine-containing Fluorescent Probes With Aggregation-induced Emission

Fluorescent probes with aggregation-induced emission(AIE)exhibit many advantages,including high quantum yield,excellent photostability and high detection sensitivity.Electron-rich triphenylamine group is usually employed to design fluorescent probes with aggregation-induced emission.In this study,two fluorescent probes based on triphenylamine have been designed,and their applications in detection and imaging for nitroreductase and hydrogen sulfide have been explored.The main contents are as follows:(1)The fluorescent probe TAE-NQS with aggregation-induced emission based on triphenylamine group and quinoline salt was designed and synthesized.Fluorescent probe TAE-NQS was successfully synthesized by coupling carbon-carbon double bond between triphenylamine and quinoline salt through nucleophilic substitution reaction and Knoevenagel condensation reaction.Then it was characterized by nuclear magnetic resonance hydrogen spectroscopy(~1H NMR).The spectroscopic properties of fluorescent probe TAE-NQS were investigated using absorption and fluorescence spectrometry.With the enzymatic reaction by nitroreductase,the recognition group of the fluorescent probe TAE-NQS is cleaved,and the near-infrared fluorescence signal at 750 nm of the resultant fluorophore appears.The fluorophore molecules produced by the fluorescent probe TAE-NQS upon responding to nitroreductase show obvious aggregation-induced emission.The fluorescent probe display great potential in the detection of nitroreductase detection in various fields.(2)The fluorescent probe TPANF with aggregation-induced emission which contains triphenylamine group was designed and prepared.TPANF was successfully synthesized by directly coupling triphenylamine and quinoline through bromination reaction and Suzuki coupling reaction.Nuclear magnetic resonance hydrogen spectrometry(~1H NMR)and high resolution mass spectrometry(HR-MS)were employed to verify the chemical structure of the probe.In the presence of hydrogen sulfide,the recognition group of the fluorescent probe TPANF is cleaved,and the resultant fluorophore molecules show reduced hydrophilicity and readily aggregate,thus the fluorescence signal enhances at 468 nm.This probe exhibits high sensitivity for hydrogen sulfide detection with a very low detection limit of 0.17?M.The probe shows low cytotoxicity,and can be used to detect and image hydrogen sulfide in cells and tumor tissues.In addition,the probe TPANF can be used to detect hydrogen sulfide in meat and to evaluate the freshness of meat.