Synthesis And Application Of Ruthenium Complex-based Phosphorescent Probes For Singlet Oxygen

Singlet oxygen(1O2) is the lowest excited state of molecular oxygen. Due to its outstanding importance in many chemical and biological processes, the development of luminescent probes specific for the detection of singlet oxygen has attracted much attention. In this work, by using2,2’-bipyridine (bpy) and4-(9-anthryl)-2,2’-bipyridine (An-bpy) as ligands, three highly sensitive and selective Ru(Ⅱ) complex-based phosphorescent probes,[Ru(bpy)3-n(An-bpy)n](PF6)2(n=1,2,3), have been designed and synthesized for the detection of singlet oxygen at room temperature. The probes themselves are almost non-phosphorescent, but can selectively react with singlet oxygen to yield the anthryl-endoperoxide derivatives [Ru(bpy)3-n(EP-An-bpy)n](PF6)2(n=1,2,3), accompanied by a remarkable phosphorescence enhancement. The new probes are highly water soluble and have a wide pH available range. The phosphorescence response of the probes towards various reactive oxygen species indicates that the probes are highly specific for singlet oxygen.The probes were used for the phosphorescence detection of singlet oxygen generated from the MoO42--H2O2system. The dose-dependent luminescence enhancement of all the probes shows the good linearity with the concentrations of1O2At the same time, a detection limit of0.17μmol/L was obtained by using [Ru(bpy)2(An-bpy)](PF6)2·...