Synthesis Of A Novel Coumarin Fluorescent Probe And Identification Of Metal Ions

With the rapid development of social economy,the pollution of heavy metal ions in the environment has attracted extensive attention of researchers.Therefore,the ion detection method,which is simple,convenient,efficient and practical,is paid more attention to by people.Compared with the traditional ion detection method,the fluorescent probe has the advantages of low cost,high efficiency and simple operation.However,there are also some deficiencies such as poor selectivity,low solubility and low quantum yield.The binding of receptors with large conjugated systems with chromophores can improve the specificity of ion recognition and fluorescence quantum yield.Therefore,the design and synthesis of this kind of small molecule compound with coumarin as the chromophores and pyridine,pyrazole,pyrimidine and polypyridine aromatic heterocyclic ring with both rich coordination group and electron acceptor is a very challenging frontier work.At the same time,the synthesis of these small molecules provides a theoretical basis for the development of metal ion fluorescent probes with good sensitivity and high selectivity.This paper mainly involves the following aspects:(1)A novel copper ion fluorescent probe was designed and synthesized with pyridine-pyrazolyl as electron donor and coumarin-Schiff as receptor.The response of the probe to various metal ions was investigated by UV-vis absorption spectrum and fluorescence spectrum.The complexation measurement ratio between the probe and copper ion and the lowest detection limit of fluorescence response were found by fluorescence titration.The functional group that the probe interacts with the copper ion is acylhydrazine group by infrared spectroscopy.(2)A novel copper ion fluorescent probe was designed and synthesized with pyridine-pyrimidine as electron donor and coumarin-Schiff base as receptor.Through UV-vis absorption spectrum and fluorescence spectrum,the response effect between the probe and a variety of metal ions,the reaction measurement ratio,and the minimum detection limit of fluorescence response were explored.The functional group that the probe interacts with copper ion is acylhydrazine group.(3)A novel ferric ion fluorescent probe was designed and synthesized by using3-acetylene-1,10-phenanthroline as electron donor and coumarin bromine as acceptor.Through UV-vis absorption spectrum and fluorescence spectrum,the response effect of the probe with a variety of metal ions and the measurement ratio of the interaction were investigated.The minimum detection limit of its fluorescence response is the lowest of the three new fluorescent probes.