Preparation And Application Of A Novel H₂S Fluorescent Probe Based On Quinoline Group

Hydrogen sulfide?H₂S?is the third endogenous gas transmitter in human body,next to carbon monoxide and nitric oxide,which is soluble in water.The concentration range of hydrogen sulfide between physiological level and toxicological level is less than two orders of magnitude,which is a great threat to the health of organisms.Therefore,it is of great significance to achieve efficient detection of H₂S.Fluorescence analysis technology has many advantages,such as good selectivity,high sensitivity,simple operation,fast detection speed,and it is suitable for cell and in vivo imaging.Due to the limitation of fluorescent materials and water solubility of the probe,the practical application value of H₂S fluorescent probe needs further study.Based on the mechanism of pet?photo induced electron transfer?and according to the strategy that the reduction of azides by H₂S can change the fluorescence intensity of the probe,the quinoline group was selected as fluorescence group and galactose ligand as target group of liver tumor cells,a series of quinoline hydrogen sulfide fluorescent probes modified by galactose were designed and synthesized.By modifying quinoline 5-site with different substituents,enhanced and ratio fluorescent probes with good fluorescence detection performance for H₂S were obtained,it has been successfully applied to the detection of sulfide and biological hydrogen sulfide in water quality.The main contents are as follows:1.By using quinoline group as the main ring framework and introducing triazole modification and galactose ligand at 5-position,we report a case of fluorescence enhanced H₂S fluorescence probe with good targeting and water solubility for liver tumor in this chapter.Because of the introduction of triazole group,the fluorescence emission intensity of the probe was enhanced obviously.The introduction of galactose ligands has greatly improved the water solubility of the probe and has been successfully used for the detection of hydrogen sulfide in water quality.The probe imaged the H2S fluorescence in tumor cells A549,Hela and Hep G-2,especially,it can effectively detect the endogenous H₂S in Hep G-2 cells.2.By using quinoline group as the main ring framework and introducing alkyne at 5-position to modify,a new ratio type of H₂S fluorescence probe was designed and synthesized.The fluorescent probe has the advantages of good selectivity,high detection sensitivity,fast reaction speed and good biocompatibility.It has been successfully used in the fluorescence imaging of H₂S molecules in Hu H-7 cells.3.By introducing alkyne modification and galactose ligands at 5-position with quinoline group as the main ring skeleton,we report a ratio type of H₂S fluorescence probe with both targeting ability and water solubility of liver tumor cells in this chapter.By introducing phenyl acetylene fluorescence group and changing the conjugation system of the probe,the probe shows the characteristics of ratio fluorescence,and has low background interference,which improves the reliability and accuracy of the detection results.The new fluorescent probe shows fast response,high sensitivity and low detection limit for hydrogen sulfide.Moreover,it has excellent water solubility and targeting for liver tumor cells,and is used for selective fluorescence imaging of H₂S in Hu H-7 cells and A549 cells.It shows a good application prospect.