The Synthesis And Applications Of Fluorescent Probes Based On Coumarin And Oxanthene

Small molecule probes are important methods for biological and environmental samples.It is helpful for environmental assessments and clinical diagnosis of diseases because of its excellent sensitivity and selectivity,short response time and small sample damage.Hypochlorite?HClO/ClO^-?is often used as bleaching agent and disinfectant,but during the process,it often produces various chlorine-containing by-products,such as chlorine,chlorate and so on,which can potentially harm the human body.Fluoride?F^-?and hydrazine?N₂H₄?widely exist in water and industrial processes.As environmental pollutants and toxic substances to human body,when exposed to them,they will cause great harm to human body.Three probes were prepared for actual samples in real water samples and cells,and portable test strips were made.?1?Hypochlorite probe based on coumarinBased on the decomposition of HClO,a turn-on probe dimethylthiocarbamic acid O-?4-methyl-2-oxo-2H-chromen-7-yl?ester?DAME?was synthesized of coumarin derivative as fluorophore and dimethylcarbamothioic chloride group with sulfide moiety as recognition group for sensing HClO with excellent selectivity.The sulfide moiety would be oxidized by HClO,and the fluorophore exhibited significant fluorescence.Probe DAME could respond to HClO in solutions within 60s and the limit of detection was 34.75 nmol L^-1.And confocal images confirmed that probe DAME could be used for recognizing HClO in living PC-12 cells.?2?Red-emitting probe for hypochlorite in living cellsFollowingthestrongoxidationofClO^-,thewater-solublered-emittingprobe3-amino-10-?diethylamino?-5,6-dihydrobenzo[c]xanthen-12-ium?probe 1?was prepared for ClO^-.Probe 1which replies excellent sensitivity with LOD of 2.41 nmol L^-1,rapid response and better selectivity to ClO^-than relevant substances,was used to monitor enzymatically generated and exogenous ClO^-in living PC-12cells.?3?Dual-responsive probe for fluoride ion and hydrazine based on test stripsDual-functional fluorescent probe 4-nitrobenzene sulfonic acid 4-methyl-2-oxo-2H-tryptophan-7-ester?probe 2?was composed for both F^-and N₂H₄ with high selectivity and sensitivity.The LOD of probe 2 for F^-and N₂H₄ were 77.82 nmol L^-1 and 29.34 nmol L^-1,respectively.The home-made test strips of probe 2provided the positive tool for F^-and gaseous N₂H₄ in different system.Probe 2 has great prospects for N₂H₄ imaging and determining in living system.