Studies of the Interaction of Ni (II) Complexes Bearing Planar Aromatic Ligands with Calf Thymus DNA

Three Nickel (II) complexes of formula [Ni(en)2](NO3)2(a), [Ni(bpy)2](NO3)2 (b) and [Ni(phen)2](NO3)2(c) (where en = ethylenediamine, bpy = 2,2 bipyridine and phen = 1,10 phenanthroline) were prepared. The structure of these complexes have been characterized by spectroscopic methods such as infrared, ultraviolet visible and nuclear magnetic resonance and conductivity measurements and elemental analysis. Interaction of these three complexes with calf- thymus DNA were carried out using ultraviolet- visible, fluorescence and jell- filterationtachniques. These complexes can denature the DNA at quite low concentrations. Complexes b and c having aromatic surface presumably intercalate in DNA. Moreover complex c can cleave the DNA into two parts and interact with both.