Study On Synthesis And Spectral Properties Of Reactive Oxygen Species And Active Sulfur Fluorescent Probes

In the course of life,the body produces many oxygen species,including reactive oxygen species,active sulfur,etc.Hydrogen peroxide,as an important active oxygen molecule,is involved in various physiological processes.However,excessive H₂O₂ can induce a variety of diseases,such as cancer,arteriosclerosis,etc.Herein,we report the simultaneous near-infrared?NIR?and two-photon imaging by a ratiometric fluorescent probe to detect H₂O₂ in living system.The probe BC employed oxonium group as novel response site and showed NIR emission.When responded to H₂O₂,the probe BC released a two-photon dye and exhibited extremely large emission shift of 221 nm,which enabled the precise measurement of the peak intensities and ratios.The probe BC showed nearly no influence in fluorescent spectra when exposed to NO for a long time,and had nearly no response to electrophilic molecules such as H₂ S,cysteine or GSH.Cysteine is one of the important semi-essential amino acids,often participates in many enzymatic reactions and possesses lots of biological functions.Herein,we present a sensitive and selective red fluorescent probe?RCys?for detecting Cys in living cells and animals.RCys utilized the rhodamine derivative as the fluorescent platform,and employe acrylate as the response site for Cys.When RCys responded to Cys,a red fluorescence was observed at 638 NM.RCys displayed obvious fluorescece response to Cys in a short time,and exhibited favorable selectivity to Cys over the other thiols including GSH and Hcy.Thiol compounds are important molecules in the cell,and they play an important role in the oxidative stress response,such as antioxidants,chelating agents that bind to the metal,and so on.Hydrogen sulfide,the simplest biological thiol,is produced in the process of enzymatic and non enzymatic processes in humans.Hydrogen sulfide could induce the proliferation of cancer cells in a concentration-dependent manner,and has close relation with the tumor growth.Monitoring the H₂ S level in real-time is of great important for understanding its roles in the cancer cell proliferation and the diagnosis of the tumor.Herein,Biotin was selected as the cancer cell-specific group and the azide group was employed as the response site for H₂ S.Under the guidance of the biotin group,BN-H₂ S can be successfully used for the two-photon imaging of H₂ S in cancer cells.