Research On Carbazole-based Reactive Fluoride Ion Fluorescent Prob

Fluoride is good for bone and dental health,but excessive intake can inhibit the synthesis of DNA and proteins,leading to diseases such as immune system metabolism disorders,reduced immunity and growth retardation in minors.Organic molecule fluorescent probes convert chemical information into fluorescence signals through interaction with specific target substances,which is a highly specific and visualizable trace analysis method.In this thesis,the fluorescent probe molecules SCT,SCC and SCP were designed and synthesized based on carbazole ring as fluorophore and Si-O bond as the identification group,and their photophysical properties were tested and applied,and the following results were obtained:The probe SCT was constructed by introducing rhodanine group,and the results showed that the SCT detection limit was low and the Stokes shift was large.Its detection limit was 82.7 n M and the Stokes shift was 140 nm.However,Ca²⁺,Ag⁺and Cu²⁺had obvious interference with the fluorescence signal of SCT to recognize fluoride ions,and the fluorescence quantum yield of the recognition product was only 25.7%,which limited the application of SCT.The probe SCC was constructed by introducing arylenitrile group,and the results showed that SCC detection limit was low,Stokes shift was large,and specificity was strong.The detection limit was 25.9 n M,the Stokes shift was 118 nm,and there was no obvious interference from common anions and cations.Due to the enhancement of probe specificity,SCC had been successfully applied to the detection of fluoride ions in river water.However,due to the low quantum yield of SCC（28.7%）,the fluorescence image obtained in cell imaging experiments had low brightness,and the imaging effect was insufficient and needed to be improved.The probe SCP was constructed by introducing pyridineacetonitrile group,and the results showed that the identification of fluoride ions by SCP not only had the characteristics of low detection limit,large Stokes shift and strong specificity,but also had the advantages of wide detection range and high quantum yield.SCP（0.2μM）quantifies fluoride ions in the 0-5.6μM range.In pure Et OH and Et OH-HEPES solvent systems,the fluorescence quantum yields were as high as 85.7%and 62.8%,respectively.As an in vitro detection reagent,it could accurately quantify n M-level fluoride ions in blood samples.Applied to cell imaging,the intracellular fluoride ion was successfully illuminated.Through the above research work,we had successfully developed a fluoride fluorescent probe SCP with high sensitivity,high selectivity and wide detection range.The probe provided a reliable quantitative analysis and visualization method for the prevention and control,diagnosis and medical research of fluorine-related diseases.