Synthesis And Properties Of Several HBT-based Fluororescent Probes For Biothiols

In recent years,fluorescent probes have been widely used in environment,chemical,biological and other fields because of its high sensitivity,good selectivity and capability of real-time,on-site in vitra and in vivo detection and so on.2-(2'-hydroxyphenyl)benzothiazole(HBT)is a good fluorphore that have excited state intramolecular proton transfer(ESIPT)effect with advantages of good photostability,large stokes shift and so on.In this thesis,we used HBT as the fluorophore,synthesized several reaction-based fluorescent probes and studied their optical sensing properties for biothiols.The main work is summarized as follows:1.We synthesized a very simple small molecular fluorescent probe(Probe 1)through one step reaction from HBT and NBD-Cl,and characterized its stucture.Studies showed that probe 1 can be used to rapidly(<150 s)?selectively and simultaneously detect and discriminate the most important biothiols:H2S(the simplest thiol),Cys/Hcy and GSH by the changes of UV-Vis and fluorescent spectra under mild conditions.Moreover,probe 1 can be used to simultaneously detect and discriminate biothiols in living cells,which indicated that probe 1 has great potential in biological applications.2.With the purpose of exploring the influence on probe 1 in detecting and discriminating H2S,Cys/Hcy and GSH,we introduced an aldehyde group to the ortho-position and para-position of the hydroxy in the HBT.Then we synthesized and characterized two new fluorescent probes(Probes 2 and 3).We investigated the optical sensing properties of probe 2 and 3.And found that these two fluorescent probes can be used to detect H2S rapidly with high sensitivity and selectivity over other biothiols under mild conditions.In addition,obvious signal changes of color and fluorescent were observed during the detection of H2S.Moreover,probe 3 can be used to detect H2S in living cells with low cytotoxicity.