Synthesis And Properties Of Fluorescent Probe Molecules Containing TPE And Schiff Base

Recently,development of fluorescent molecule probes to detect metal ions and biological macromolecules has attracted people's attention in the fields of chemistry,environmental science,life science,and medicine.Tetraphenylethylene(TPE),which is easily to be synthesized and modified was usually introduced into the design of fluorescent sensors for recognition of biological macromolecules because of the excellent AIE properties.Schiff bases for recognition of metal ions have been widely used due to their excellent photoluminescence properties,special chelation sites,and significant light signals.Herein,series of fluorescent molecular probes containing TPE and Schiff base were designed and synthesized for the detection of heparin and various metal ions.It provides essential candidates for the development of new fluorescent molecular probes for the detection of biological macromolecules and metal ions.The research contents are as follows.1.Compound TPE-NH2 in which a hydrophobic tetraphenylethylene(TPE)was connected to four positively charged amino groups through a flexible alkyl chain was designed and synthesized,and the structure was characterized by 1H NMR,13C NMR and ESI-MS.TPE-NH2 can quantitatively detect heparin through electrostatic interaction.The linear range is 0-2 ?g/mL,and the detection limit can reach 35.89 ng/mL.At the same time,due to the higher affinity between heparin and protamine,the TPE-NH2/Hep complex can further detect protamine.Moreover,TPE-NH2 exhibited good biocompatibility and can detect heparin in the serum matrix quantitatively.2.In order to develop fluorescent molecular probes for recognition of metal ions with high selectivity and sensitivity,acetylated glucose with good biocompatibility was introduced into Schiff bases,and four compounds A,B,C1,C2 were designed and synthesized.Their structures were confirmed by 1H NMR,13C NMR and ESI-HRMS,and the response to different metal ions were investigated by UV and fluorescence spectrophotometry.The results show that,(1)Al3+could be quantitatively detected by probe A,with a linear range of 3-20?M and a detection limit of 10.45 nM;(2)Cu2+ and Zn2+could be identified by probe B quantitively,with linear ranges of 1-10 ?M and 3-10 ?M,and detection limits of 0.6 ?M and 17.87 nM,respectively;(3)Mg2+ could be recognized by probe Ci selectivity and sensitivity,with a linear range of 0-10 ?M,and a detection limit of 9.17 nM;(4)Cu2+ could be detected by probe C2 quantitatively,with a linear range of 0-10?M,and a detection limit of 0.19?M.The structures of compounds A,B,Ci and C2 are shown below.