Several Coumarin-based Fluorescent Probes Are Used For The Detection And Imaging Of Zinc Ions And Active Sulfur

To completely elaborate the roles of intracellular biological species in biological events,various detection technologies have been developed and improved.However,most of the detection technologies require tedious sample preparation,time-consuming cell and tissue lysis,and high cost operations.It is a challenging research job to realize the real-time and in situ tracking of bioiogical species in living systems.Therefore,it is extremely urgent to construct advanced chemical tools to meet the requirements of mapping the distribution of intracellular various relative biomarkers.Among the detection technologies,small molecule fluorescent probe bioimaging technology is considered as a powerful tool for real-time,noninvasive,and in situ visualization of diversified species in living cells.When capturing analytes,the fluorescent probe switches on its specific fluorescence without damaging cells and provides the detailed information of biological roles of intracellular biomolecules and ions.To date,the available fluorescent probe for intracellular species detection has been making advanced progress.However,fluorophore platform which possesses high fluorescent quantum yield,excellent biocompatibility,strong fluorescence signal,stable fluorescence emission,and good structural flexibility is still an important strategy that should be considered in the design and synthesis of fluorescent probes.Therefore,we choose coumarin dye with excellent chemical and biological properties as fluorophores,and promote the use of fluorescent probe for life imaging analysis without causing damage to living organism.In recent years,coumarin platform has been widely used in the design of organic small molecule fluorescent probe due to good biocompatibility,stable fluorescence emission,and good structural flexibility.The structure has been widely used in the development of fluorescent chemical sensors in the fields of molecular recognition,molecular imaging,bioorganic chemistry,analytical chemistry,materials chemistry,and biology and medicine.The specific work of this article will be presented in the following five parts:Chapter one:A simple introduction of the concept,composition,types of fluorescent probes.A simple summery on the development status and the research background of coumarin fluorescent probes for zinc cation(Zn2+),reactive sulfur species(RSS)such as cysteine(Cys)and sulfur dioxide derivatives sulfite(SO32-)and bisulfite(HSO3-).Focus on the research ideas of this paper.Chapter two:The design and synthesis of two-photon fluorescent probes CHP-R(CHP-H and CHP-CH3)and the detection and bioimaging analysis of Zn2+in living system.The probes consist of two moieties:7-amino coumarin dyes as the two-photon fluorescence transducer,2-hydrazino pyridine as the fluorescence modulator and Zn2+chelator.CHP-H and CHP-CH3 exhibite high sensitivity,selectivity,and low limit of detection(19 and 25 nM)in simulated physiological systems.The probe CHP-H can track Zn2+concentration fluctuations in normal cells and ischemia-reperfusion(I/R)model cells.CHP-H possess the ability to penetrate deep tissues and real-time Zn2+ bioimaging in the mice brain hippocampus and is utilized to verify that the mutual interaction between Zn2+and nitrosyl hydrogen(HNO)was unidirectional.Chapter three:The design and synthesis of two-photon fluorescent probe CUKF and the dual-site bioimaging analysis of Cys and sulfur dioxide derivatives SO32-in living system.The probe CUKF is formed by the aldol condensation reaction of amino-coumarin methyl ketone and p-dibenzaldehyde.The formed ?,?-unsaturated ketone serve as the reaction site for Cys,and the terminal formyl group acts as the SO32-reaction site to undergo addition reaction with SO32-.CUKF exhibits excellent optical properties for the detection of Cys and SO32-under simulated physiological condition and possesses good biocompatibility in the organism.Furthermore,the probe CUKF can be applied to the detection and imaging analysis of Cys and SO32-in normal cells and epileptic model cells to realize the dual-channel species analysis and bioimaging via a single probe.Chapter four:Design and synthesis of fluorescent probe for cysteine/bisulfite response and intracellular imaging research.The probe is prepared from 7-amino salicylaldehyde via Michael addition reaction.Under simulated physiological condition,Cou-F has the advantages of high sensitivity,strong specificity,rapid response,and low cytotoxicity.Cou-F is successfully applied to Cys and HSO3-imaging study in RAW246.7 cell lines.Chapter five:Summary of the research work and future examination outlook.In order to better adapt to the development of probes and meet the demands of detection and bioimaging,we optimize the probes based on the current work to design to synthesize a series of novel fluorescent probes.