Synthesis, Characterization, DNA Binding and Nuclease Activity of Cobalt(II) Complexes of Isonicotinoyl Hydrazones

Cobalt(II)  complexes of isonicotinoyl hydrazones of two series of ligands have been synthesized and characterized on the basis of elemental analyses, molar conductance, magnetic moment, mass, IR, UV spectral data. Electrochemical behavior of ligands and complexes has been investigated by using cyclic voltammetry. Cyclic voltammetric studies reveal that the oxidation/reduction potentials of all complexes are shifted towards positive or negative values than its corresponding ligands. The interactions of these complexes with calf thymus DNA have been studied by using absorption studies. Bathochromic shift and hypochromism suggest that the intercalative mode of binding of complexes with DNA. Their DNA cleavage activity of complexes was studied on double-stranded pBR322 plasmid DNA using gel electrophoresis experiments in the absence and presence of oxidant (H2O2) and reductant (DTT).