Synthesis And Application Of Fluorescent Probes Based On Xanthene

Fluorescent molecular probe technology has attracted widespread attention in recent years due to its advantages of fast,simple and visual detection of analytes.The fluorophore is the important part of fluorescent molecular probe,and xanthene fluorophores are commonly used to construct fluorescent molecular probes due to their good photobleaching resistance and high fluorescence quantum yield.In this paper,a number of small molecule fluorescent probes based on xanthene backbone were designed and synthesized by introducing analyte-specific recognition groups.These probes were used for the identification of target ions.The specific contents are as follows:In the second chapter,we designed and synthesized two small molecule fluorescent probes Rh-p-Ap and Rh-o-Ap by introducing recognition sites p-aminophenol and o-aminophenol to Rhodol dyes.Both probes can selectively recognize Cl O^-.After reaction with Cl O^-,the fluorescence emission of both probes was significantly enhanced,and the quantitative detection of Cl O^-was realized according to the change of fluorescence intensity after the reaction with Cl O^-.The fluorescence intensity of Rh-p-Ap has a linear relationship with the concentration of Cl O^-within 0～45μM,and the detection limit is as low as 57.63 n M.The fluorescence intensity of probe Rh-o-Ap is linear with the concentration of Cl O^-in the range of 0～80μM,and the detection limit is 67.94 n M.Both probes are biocompatible and can be used for of Cl O^-imaging in Hela cells.In chapter three,a new rhodamine fluorophore Rh-Ip was synthesized,and then was modified to a fluorescent probe Rh-Ip-Hy.The probe is non-fluorescent.When it reacts with Hg2+,the spirolactam structure in the probe opens and emits strong fluorescence.The color of the solution changes from colorless to red,realizing the detection of Hg2+.There is a good linear relationship between the fluorescence intensity of probe and Hg2+concentration,with a linear range of 0～80μM.The detection limit is 57.57 n M.The probe can be used not only to detect Hg²⁺in solution,but also to image Hg²⁺in living cells.