Synthesis Of Fluorescent Probes For Detection Of Bisulfite And Cysteine And Their Applications In Living Cells

With the development of modern life science,in order to have deeper understanding in the process of human life and the mechanism of various diseases,researchers eager to gain intuitively functional information of molecules,which participate in physiological action.In recent years,fluorescent probes gradually become an indispensable instrument in the research field of bioimaging,medical diagnosis,modern medicine,bioscience due to high sensitivity,high selectivity,low reaction time,less dosage,operation simple,real-time monitoring,especially in the field of the detection of physiological molecules,and fluorescence imaging of organs in organism.Therefore,in order to have deeper understanding in the influence of physiological molecules,it is of great importance to develop novel organic fluorescent probes which possess high sensitivity,high selectivity,high spatical regulation and sample nondestructive.Two novel organic fluorescent probes had been designed and synthesized in this paper,which can be used to detect bisulfite,and cysteine belonging to physiological amino acid.They not only have excellent opticical and detection performance,but also can be successfully used to the analysis of cellular imaging.1.Based on ESIPT and ICT process,we designed and synthesized a novel fluorescent probe HBT-TCF for colorimetric and ratiometric detection of bisulfite.The probe was consisted of molecular fragments of HBT and TCF.HBT and TCF were linked by an ethylene bridge,enabling the probe to have NIR emission property.The ethylene bridge was selected as reaction site with HSO₃^-based on Michalel-type addition reaction.By interrupting conjugated structure between HBT and TCF,the emission peak could be changed from 665nm to 445 nm.The excellent properties of probe HBT-TCF are as follows:?1?A good linear correlation between fluorescent intensity and the concentration of HSO₃^-ranging from 5?M to 40?M with a coorelation coefficient?R2?of 0.993.The detection limit of the probe was101 nM.?2?A wide suitable pH range of 3.0-10.0?3?A large emission wavelength shift?200nm?,which solved the problem of channeling peak,reducing the optical losses of HBT-TCF in the process of detection.Based on the excellent optical properties of HBT-TCF,we successfully applied the probe to the detection of bisulfite in MCF-7 cells.2.Based on the typical structure properties of coumarin and fluorescein,we designed and synthesized a novel fluorescent probe for detection of cysteine.It can change intramolecular structure and change distribution by the addition-cyclization reaction between cysteine and acrylate,realizing quantitative detection of cysteine.According to experimental result,the excellent properties of probe CF-AC are as follows:?1?A good linear correlation between fluorescent intensity at 525 nm and the concentration of cysteine ranging from 0?M to 40?M?2?Two new fluorescent emission peak at 525nm and 650nm appeared upon addition of cysteine.The multichannel imaging of cysteine can be realized through the selection of imaging area.?3?Probe CF-AC had been successfully applied to the detection of cysteine in MCF-7 cells.