Design,Synthesis And Application Of Novel Europium(?) Complex-Based Luminescent Probes

Lanthanide complexes possess several excellent advantages,including long luminescence lifetime and large Stokes shift,which can effectively eliminate the background fluorescence and light scattering from the complicated biological samples by the combination of time-gated luminescence analysis technology,and have exhibited important application value in the fields of biological sciences and medicine.The rapid development of time-gated luminescence microscopy bioimaging technology provides new opportunities for the application of luminescent lanthanide molecular probes.There are numerous reactive small molecules that have an important influence on life activities in organisms,such as NO,H₂S,HClO,¹O₂ and so on.Quantitative detection of these reactive small molecules can provide the real-time understanding of the activity state of cells or organisms.In this paper,two types of new lanthanide complex were designed and synthesized for time-gated luminescence detection of HClO and NO,respectively.Based on these results,the bioimaging applications of the probes were carried out.The main contents of this thesis are as follows:1.Synthesis and application of a visible-light-excited europium???complex-based luminescent probe for the selective detection of hypochlorous acid in lysosomes.By modifying the ligand 5-?4"-chlorosulfonyl-1',1"-diphenyl-4'-yl?-1,1,1,2,2,3,3-heptafluoro-4,6-hexanedione?CDHH?with a lysosomal targeting group and simultaneously introducing the visible-light-sensitized dipyrazotriazine derivative ligand 2-?N,N-diethylanilin-4-yl?-4,6-bis?3,5-dimethylpyrazol-l-yl?-l,3,5-triazine?DPBT?,anovel visible-light-excitedeuropium???complex-basedluminescentprobe,[Eu?Lyso-CDHH?₃?DPBT?],was designed and synthesized.The probe showed a maximum excitation wavelength at 407 nm with an excitation window extending to 450 nm,and a high luminescence quantum yield up to 41.7%.The luminescence of the probe was strongly quenched with a 155-fold decreasement after it reacted with HClO,proving the high sensitivity and selectivity for the detection of HClO.The introduction of a lysosomal targeting group?morpholine moiety?allows the probe to enter the lysosome of living cells after their co-incubation,and the time-gated luminescence imaging of HClO in lysosomes has been accomplished.2.Synthesis and application of a new europium???complex-based luminescent probe for the selective detection of nitric oxide.A terpyridine derivative ligand 4-?[2,2';6',2'']terpyridin-4'-yloxy?-benzene-1,2-diamine?TDBD?containing a NO-specifico-diaminophenyl group was designed and synthesized,and thenitcoordinatedwitheuropium???ionandtheb-diketoneligand5-?1,1”-bis-phenyl-4'-yl?-1,1,1,2,2,3,3-heptafluoro-4,6-hexanedione?DHH?to form a novel time-gated luminescent probe[Eu?DHH?₃?TDBD?].The probe itself was weakly luminescent.After it reacted with an aqueous solution of NO in air to form the triazole derivative,the luminescence intensity of the reaction product significantly increased up to an about 7-fold enhancement.The probe shows a good linear relationship and selectivity for the detection of NO.In addition,the probe can be applied for the time-gated luminescence imaging detection of NO in cells.