Synthesis And Properties Of Organic Small Molecule Fluorescent Probes

In recent years,as a novel detection method,fluorescent probe have played important roles in many fields.Compared with traditional detection methods,fluorescent probe showed the advantages of good selectivity,high sensitivity,simple operation and excellent performance in vivo imaging.The development of new fluorescent probes have become the focus of research.Among the numerous fluorescent probes,small molecule fluorescent probes have defined molecular weight and element composition,with excellent advantages in synthesis analytical performance,reproducibility and biological imaging.In this paper,small molecular fluorescent probes for Cu²⁺,Fe³⁺and CN^-were synthesized with coumarin,rhodamine,benzothiazole.And their application in actual detection and biological imaging were studied.1.Copper ion(Cu²⁺)is a metal element necessary for organisms and human body.It showed a key role as a catalytic cofactor for a variety of metal enzymes,including tyrosinase and superoxide dismutase.However,the transitional of Cu²⁺was used,may lead to environmental problems.This paper,a small-molecule fluorescent probe was gained by coumarin as the parent that could recognize Cu²⁺through naphthalimide modification.The probe had highly selective for detecting Cu²⁺in HEPES buffer（10 m M,p H=7.4）/CH₃CN（1:4,v/v）,and low detection limit.And it was used for in vivo imaging of C.elegans.2.Iron ions(Fe³⁺)showed important role in the chemical industry,environment and organisms,especially in the formation of red blood cells,the transportation and storage of proteins,and the process of oxygen metabolism.However,the deficiency and overload of Fe³⁺could cause various dysfunctions of the organism and the occurrence of diseases.In this paper,an"off-on"fluorescent probe could recognize Fe³⁺was synthesized by rhodamine as a parent.The probe recognized Fe³⁺selectively in HEPES buffer（10 m M,p H=7.4）/CH₃CN（2:3,v/v）,with a low detection limit,and could qualitatively and quantitatively detect water pollution caused by Fe³⁺.The probe has also been successfully used for imaging of C.elegans,mice and plant tissues.3.Cyanide ion（CN^-）has been studied because of its highly toxic properties,especially CN^-quickly binds to the ferric ion in cytochrome oxidase in the human body,inhibiting the enzyme activity,making the tissues unable to use oxygen and causing some disease.In this paper,a small molecule fluorescent probe was analyzed by the benzothiazole.The probe had high selectivity,high sensitivity and low detection limit for CN^-in DMSO:H₂O=（8:2,20μM,v/v）solution.The probe interacted with CN^-,the obvious color changed and fluorescence enhancement were observed.The probe was successfully applied to He La cells and real-time vivo imaging in mice.