The Research On Novel Two-Photon Fluorescent Probes Based On Naphthalene Derivatives

Various small molecules in the organism play important roles in life activities.The concentration of these molecules is closely associated with human's health.Two-photon fluorescence probes have broad prospects in the field of biological analysis and detection due to their characteristics such as easy synthesis,simple operation,long wavelength excitation,and deep tissue penetration depth.The naphthalene derivatives are excellent two-photon fluorescent substances,which have a large two-photon absorption cross-section.Combining naphthalene derivatives with compounds or materials that selectively respond to small molecules,and constructing novel and efficient two-photon fluorescent probes have significant advantages for the analysis and detection of small molecules.In this study,the two-photon properties of naphthalene derivatives were utilized to constructed a series of two-photon fluorescence probes by combining several substances that react with small molecules.These probes were utilized for the analysis of sulfur dioxide and derivatives,nitroxyl and hypochlorous acid.They exhibit high selectivity,high sensitivity and good biocompatibility.They were also applied to cell imaging.These researches provide a theoretical reference for the detection of small molecules in vitro and in vivo.In the second chapter,we chose hemicyanine dyes as the reactive groups of sulfur dioxide and derivatives.The structure of hemicyanine dyes were changed due to the nucleophilic addition reaction between sulphur dioxide derivatives and the unsaturated carbon-carbon double bonds of hemicyanine dyes.This reaction affected the fluorescence resonance energy transfer between naphthalene derivatives and hemicyanine dyes,realizing the analysis and detection of sulfur dioxide derivatives and the imaging of cells and tissues.In chapter 3,based on the Staudinger-like reaction between triphenylphosphine and nitroxyl,we attached triphenylphosphine to the rhodol fluorophore group.When nitroxyl attacted the probe and reacted with triphenylphosphine group,the ester group on the structure of rhodol fluorophore was hydrolyzed.So that the fluorescence resonance energy transfer between the naphthalene derivative and the rhodol fluorophore was affectd,thus the detection of nitroxyl was realized.In chapter 4,we utilized the gold nanoclusters to react with hypochlorous acid.Hypochlorous acid oxidized gold nanoclusters and quenched the fluorescence of the gold nanoclusters.At the same time,the fluorescence of the naphthalene deriva tives was not affected by hypochlorous acid,which can act as a comparison.This probe showed a ratiometric detection of hypochlorous acid.