Design,Synthesis And Application Of Fluorescent Probe For Reactive(RSS)and(ROS)detection Based On Coumarin Or Rhodamine Matrix

Fluorescent probes are widely used in medicine,biological cell imaging and other fields because of their advantages of high sensitivity,fast response speed,high selectivity and strong anti-interference ability.At present,the design and synthesis of fluorescent probes with specific functions have become a research trend.Biologically active sulfur?RSS?species?such as H₂S,Cys/Hcy,and GSH?and biologically active oxygen?ROS?species?such as HCl O,H₂O₂,O₂^-,etc.?are a series of active small molecules widely present in organisms.They play an important role in maintaining the normal function and signal transmission of living cells in tissues.The abnormality of its content is often closely related to the occurrence of various diseases.Therefore,the detection of the above active molecules,especially the simultaneous detection of multiple active molecules,is of great significance.In this paper,using rhodamine and coumarin as the matrix,a series of fluorescent probes for detecting and distinguishing RSS/ROS small molecules were designed and developed.The specific work is as follows:1.Using a phenothiazine group with strong electron donating ability as an electron donor,a total of 12 new near-infrared rhodamine fluorescent dyes PRH1-PRH6 and RH1-RH6 were designed and synthesized,and the spectral properties of these dyes were systematically studied.In different solvents,the UV absorption of series phenothiazine rhodamine dyes PRH1-PRH6 is between 584-630 nm,the fluorescence emission is between 732-760 nm,and the Stokes shift can reach 122-159 nm.This series of dyes also has a high molar absorption coefficient?0.123-11.54?×10⁵M^-1cm^-1,quantum yield and fluorescence lifetime are between 0.0072-0.0672 and0.41-2.00 ns.The ultraviolet absorption of the esterified dyes RH1-RH6 is between 521-525 nm,the fluorescence emission is between 682-760 nm,molar absorption coefficient?0.1064-1.39?×10⁵M^-1cm^-1,quantum yield and fluorescence lifetime are between 0.0005-0.0465 and 0.31-3.4ns,and the Stokes shift is further increased to 120-173 nm.2.Research shows that RH1-RH6 can also be used as a near-infrared ratio rhodamine-based fluorescent probe for detecting HCl O.They have good water solubility,high selectivity,low detection limit?LOD=38 n M?,and fast response speed?t=10 s?,low cytotoxicity,large Stokes displacement,good light stability,etc.3.By introducing resorufin as a leaving group to coumarin,designed and synthesized a fluorescent probe Lyso-RC that can simultaneously detect and distinguish H₂S,Cys/Hcy and GSH.Lyso-RC itself does not fluoresce,adding H₂S,Cys/Hcy and GSH can induce the probe to different fluorescence emission:red?604 nm?,blue-red?480 nm+602 nm?,green-red?542nm+602 nm?.In addition,the probe has higher sensitivity to H₂S,Cys/Hcy and GSH?LOD0.38 n M,27 n M,33 n M,16 n M?,faster response?t<30 min?,stronger anti-interference ability and low cytotoxicity.Moreover,Lyso-RC is a lysosomal-targeted probe with a Pearson Coefficient of 0.96.The probe was successfully applied to multi-channel imaging of H₂S,Cys/Hcy and GSH in lysosomes.This probe provides a strong and reliable molecular tool for further study of the complex relationship between H₂S,Cys/Hcy and GSH.