Development Of Fluorescence Probe For Hydrogen Sulfide And Hydrogen Polysulfides And Their Application In Biological System

Hydrogen sulfide（H₂S）and hydrogen polysulfides（H₂Sn,n>1）are widespread in body,belonged to reactive sulfur species（RSS）family.H₂S was one of the important endogenous gasotransmitters in physiological processes.H₂S was played a physiological and pathological role in biological systems.H₂Sn was produced by which H₂S was oxidized or enzyme catalyzed in the cell.H₂Sn was more effective than H₂S in some physiological processes.So H₂Sn was also considered which has important physiological effects in biological systems.Howere,physiological functions and pathological mechanisms of H₂Sn were still poorly understood.In this work,in order to better understand the biological functions and pathological mechanisms of these molecules in organisms,it is significant to develop a efficient methods that could rapidly and efficiently detect H₂S and H₂Sn in vivo.Two probes for the detection of H₂S and H₂Sn were synthesized based on the properties of them.This work contains three chapters.The specific content is as follows:Chapter 1.The chemical properties and biological functions sulfur-containing small molecules including H₂S,H₂Sn were introduced,and the recent research progress of fluorescent probes for sulfur-containing small molecule was summarised.Chapter 2.Development and application of a fluorescent probes for H₂S based on nitroso group as the recognition group.Based on nitroso rapidly tranfered to corresponding amino groups by H₂S,a fluorescent probe was developted using a benzopyranyl dye as a fluorescent group and a nitroso group as a recognition group.Introducing nitroso group with electron-withdrawing effect to probe 4,fluorescence intensity of probe 4 displayed relative weak due to nitroso group would quenching its fluorescence.The probe 4 reacted with H₂S,nitroso group was rapidly tranfered to the corresponding amino group,which the electron-withdrawing nitroso group was tansfered to the electron-donating amino group.The fluorescence intensity of the probe 4 at 625 nm is dramatically increased.The remarkable increase influorescence intensity was reached a pateat with in 5 min.Fluorescence intensity enhancement was showed a good linearity with H₂S of the range from 0 to 4 μM（R2=0.993）.The detection limit is calculated to be 29 n M.The probe 4 is applied in fluorescence imaging in human hepatoma cells SMMC-7721.Chapter 3.Development and application of a probe for the determination of H₂Sn and H₂S by UV-vis absorption based on Methyl aziridine-2-carboxylate.A probe is synthesized H₂Sn and H₂S based on methyl aziridine-2-carboxylate as the recognition group for H₂Sn,the NBD scaffold seleted as a group recognized for H₂S.A strong absorption of the probe A1 was measured at 393 nm.Reacted with H₂Sn,Absorption of the probe A1 was displayed with the result of a decrease at 393 nm and a increase at 472 nm,due ring-opening reation of Methyl aziridine-2-carboxylate by the nucleophilicity of H₂Sn;And absorption of the probe A1 was measured with a decreased at 393 nm with the concomitant increase at 536 nm owing to substitution reaction of NBD dyes at the 4 position by H₂S.In this way,H₂Sn and H₂S would be distinguished by probe A1.Probe A1 had a higher selectivity H₂Sn and H₂S than other biological thiols.Absorbance was illustrated a good linearity with H₂S2 of the range from 0 to 20μM and exhibited a good linear relationship with H₂S of the range from 0 to 5 μM.