Synthesis And Properties Of Fluorescence Probe For Detection Of Biothiols

A mercapto amino acid in an organism,such as cysteine,homocysteine and glutathione play an important role in the body's physiology.At present,the recognition of biothiols methods include the HPLC,CE,MS etc,while the fluorescent probe posses fast response speed,high sensitivity,low cost,simple operation,high temporal and spatial resolution,which has been widely used in the fileds of chemistry,biology and medcine.In recent years,many fluorescent probes have been developed for the detection and study of biothiols based on the strong nucleophilic properties of the sulfhydryl groups,showing a good application prospect.In this paper,four pyrazolines and two quinolinones probe were designed and synthesized on the basis of the relevant literature and the previous work of our research group.The structure of the probe molecules was characterized by HRMS,¹H NMR and ¹³C NMR.Their optical properties were studied by UV-Vis absorption spectroscopy and fluorescence spectroscopy.The recognition mechanism of the probe was further studied by HRMS.1.Four probes(A,B,C and D)were designed and synthesized for detecting Cys using pyrazoline as the fluorophore and acrylamide as the reaction site of thiols.These probe can efficiently detect Cys in PBS:DMSO=7:3(V/V)solution without the influence of other amino acids and anions,but the Hcy and GSH can interfere with the recognition of probe toward Cys.The recognition limit of the probe was as low as 0.2?M and its response time was 150 min.The probe has good optical properties in the range of human physiological p H,indicating that the probe possess potential for biological application.2.Two probes(E and G)were designed and synthesized for detecting Cys using quinolinone as the fluorophore and acrylate as the target group based on ESIPT mechanism.The probe was able to detect Cys rapidly in PBS p H 7.4 solution and its response time was reduced to 15 min and its recognition limit was as low as 0.6?m.The probe has a good fluorescence response toward Cys in the presecence of other analytes.The mechanism of probe E for detecting Cys was studied and further verified by HRMS.