Design, Synthesis And Application Of New Europium(Ⅲ) Complex-based Luminescent Probes For The Specific Detection Of Nitric Oxide

With the combination of time-gated fluorescence analysis technology,lanthanide complex-based luminescent probes exhibit advantages of high sensitivity and high selectivity,and have been widely applied in biological analysis and clinical medicine because of their characteristics of sharp emission peak,large Stokes shift,long luminescence lifetime,etc.Nitric oxide（NO）,as an important signaling molecule in vivo has vital impacts on various physiological activities of organisms.Abnormal levels of NO can cause cancer,Alzheimer’s disease,and neurodegenerative diseases.Therefore,it is important to establish a method for detecting NO with high sensitivity and quick response.In this work,by introducing the o-diaminophenyl group to the Eu³⁺complexes as a recognition group of NO,two time-gated luminescence probes have been designed and synthesized.The time-gated luminescence detection methods have also been established for NO in the solution media,living cells and in vivo.The contents of this thesis are divided into the following two parts:1.Synthesis and application of new NO-responsive Eu³⁺complex-based luminescent probeFirstly,a terpyridine derivative ligand,4-（4-[2,2’:6’,2’’]-terpyridine-4’-yl-phenoxy）-benzene-1,2-diamine（DAPT）,was designed and synthesized using o-diaminophenyl as a specific reaction group of NO.Then it was coordinated with a?-diketone ligand DHH and Eu³⁺to form a new time-gated luminescence probe[Eu（DHH）₃（DAPT）].The probe shows only weak luminescence,and a 9-fold luminescence enhancement is acquired after its reaction with NO.The interference experiment toward other species indicates that the probe has good selection to NO.The probe has been successfully applied for the establishment of time-gated luminescence measurement method for NO in aqueous media and time-gated luminescence imaging measurement method for NO in living cells and zebra fish.2.Synthesis and application of NO-responsive long-wavelength-excited Eu³⁺complex-based luminescent probeOn the basis of the research for the probe[Eu（DHH）₃（DAPT）],a long-wavelength-excited Eu³⁺complex-based luminescent probe[Eu（pfppd）₃（DAPT）]was synthesized by replacing the ligand DHH with the ligand4,4,5,5,5-pentafluoro-1-（phenanthrene-3-yl）-1,3-pentanedione（pfppd）that has long absorption wavelength.Compared with the probe[Eu（DHH）₃（DAPT）],the maximum excitation wavelength of the probe[Eu（pfppd）₃（DAPT）]is red shifted by 15 nm(?_ex=350 nm),and it is noteworthy that the excitation intensity of the probe at 380 nm reaches to 74.3%of the maximum excitation intensity,indicating the achievement of long-wavelength excitation.Moreover,[Eu（pfppd）₃（DAPT）]shows better stability.The probe has been applied for the time-gated luminescence imaging of NO in living cells.