Synthesis And Application Of Ruthenium(â…¡) Polypyridyl Complex-Based Phosphorescence Probes

Transition metal complexes based on metal to ligand charge transfer (MLCT) emission have a lot of advantages, such as large Stokes shifts, good photo stability and long luminescence lifetime. Ruthenium(Ⅱ) polypyridyl complex, which is an octahedral coordination compound, has been widely used in many fields, such as supramolecular self-assembly, luminescence assay and photoelectric conversion. In this thesis, two kinds of ruthenium(Ⅱ) polypyridyl phosphorescence probes were successfully designed and synthesized for the selective detection of bioactive molecules by introducing different recognition moieties.First, a binuclear ruthenium(Ⅱ)-copper(Ⅱ) complex-based phosphorescence molecule,[Ru(bpy)2(phen-cyc)Cu](PF6)4(bpy:2,2’-bipyridine; phen:1,10-phenanthroline; cyc:1,4,7,10-tetraazacyclododecane), has been designed and synthesized for selective detection of hydrogen sulfide. The phosphorescence intensity of the probe is almost completely quenched by Cu2+. Upon reaction with hydrogen sulfide, a remarkable-130-fold increase in phosphorescence intensity would be afforded owing to the high affinity of sulfide to Cu2+. The dose-dependent phosphorescence enhancement of the complex shows a good linearity in the hydrogen sulfide concentration range of2to20uM with a detection limit of21.60nM for hydrogen sulfide. In addition, the phosphorescence response of [Ru(bpy)2(phen-cyc)Cu](PF6)4to hydrogen sulfide is rapid and highly selective to distinguish hydrogen sulfide, which is available for sensitive phosphorescence detection of hydrogen sulfide in aqueous solutions.In addition, a novel ruthenium(Ⅱ) polypyridyl complex-based phosphorescence probe,[Ru(bpy)2(bpy-DNS)](PF6)2, has been synthesized for selective phosphorescence detection of thiols by introducing a2,4-dinitro-phenyl group. The phosphorescence intensity of the probe is very weak. However, a remarkable～80-fold increase in phosphorescence intensity would be afforded after reaction with GSH. The dose-dependent phosphorescence increase of the complex shows a good linearity in the GSH concentration range of5～90μM with a detection limit of1.04μM for GSH. Moreover, the phosphorescence response of [Ru(bpy)2(bpy-DNS)](PF6)2to GSH is sensitive and selective to distinguish GSH over other amino acids, which is available for phosphorescence detection of GSH in aqueous solutions.