Synthesis And Properties Of Novel NIR Fluorescent Probes Based On DCM

Fluorescence detection is more attractive than several other analytical techniques because which is high sensitivity,excellent selectivity and specificity.Fluorescent probes are potentially suitable for biologic imaging and temporal resolution in living cells.Basically,the fluorescent probes are based on the unique increase or decrease in the emission intensity signal in the detection of biological species of molecules,so that the fluorescent probe is a simple and convenient detection tool.Dicyanomethylene（DCM）compounds as an important red fluorescent dyes,which are widely used in electroluminescence,optical materials,dye-sensitized solar cells,chemical molecular sensors and other fields.Based on its own structural characteristics,the recognition mechanism of DCM compounds are usually based on Intramolecular charge transfer（ICT）processes.The DCM compounds have a fluorescent wavelength of usually above 600 nm,moreover,they have a high fluorescence quantum yield,which provide a greater use space for its application in the organism.Based on the above considerations,this paper through the DCM compounds for further structural modification.Six new near-infrared fluorescent probes Lx1-Lx6 were synthesized,all of which were new compounds that were not reported.1.The probes Lx1,Lx2,Lx3 have a well-specific identification of hydrazine hydrate.The probe Lx2 in DMSO and water（7:3,v/v,10 mM PBS,pH=7.4）and the probe Lx3 in DMSO and water（4:1,v/v,10 mM PBS,pH=7.4）was detected in the ratio and colorimetric can identify N₂H₄·H₂O,moreover the probe Lx3 was more sensitive than the probe Lx2.At the same time,the tap water test can prove that these two probes can detect N₂H₄·H₂O in drinking water.Cell imaging experiments show that these two probes can be successfully applied to the detection of N₂H₄·H₂O in cells.2.The probe Lx4 utilizes nucleophilicity of SO₃^2-to characterize SO₃^2-with good specificity,the reaction speed is fast,and be able to naked eye recognition.3.The probe Lx5 reduced-NO₂ to-NH₂ by using H₂S reduction.The probe Lx5 can specifically recognize H₂S in a DMSO aqueous solution（PBS buffer solution）.4.The probe Lx6 responds quickly in a pure Tris-HCl system to identified H₂S.The probe Lx6 can be used to quickly and accurately detect H₂S in the environment using the test strip.