钌(Ⅱ)配合物与核酸作用的研究主要集中于作用的本质和键合位点等问题,对键合过程的动力学研究报道很少.我们在钌配合物与核酸键合性质的研究中发现,无论是双核还是单核钌配合物,都可能存在明显的RNA键合动力学效应.
The binding kinetics properties of three Ru ( Ⅱ ) complexes of [ Ru ( bpy ) 2 ( dhipH3 ) ] ( ClO4 ) 2,[ (bpy) 2 Ru ( eipcH ) ] ( ClO4 ) 2 and [ ( bpy ) 2 Ru ( ebipcH2 ) Ru ( bpy ) 2 ] ( ClO4 ) 4, where bpy = 2,2'-bipyridine, dhipH3 = 3,4-dihydroxyphenyl- ( imidazo [ 4,5 -f] [ 1,10 ] phenanthroline ), eipcH = N-ethyl-4- ( imidazolo [ 4,5-f] - ( 1,10-phenanthrolin ) -2-yl ) carbazole, and ebipcH2 = N-ethyl-4,7-bis ( imidazolo [ 4,5-f] - ( 1,10-phenanthrolin)-2-yl) carbazole, with yeast-RNA were investigated by monitoring the decays in absorbance for π-π^* absorption peaks at 286 nm with binding time. The decay curves for the complexes were well fitting to biexponential decay functions with half-life times for rapidly-decayed components being 0. 006, 0. 02 and 0. 8 min, and those for slowly-decayed components being 0. 7, 4. 2 and 103 min, respectively. The rapidly- and slowly-decayed components are probably due to electrostatic interaction and aromatic base stacking of the RNA with the Ru ( Ⅱ ) complexes, respectively. The results indicate that not only binuclear complexes but also mononuclear complexes can slowly bind to the RNA depending on the molecular structures of the complexes.