Abstrait

Investigations on nuclease activity of mixed ligand-copper(II) complexes with aromatic oximes and heterocyclic bases

M.S.Surendra Babu, Pitchika.G.Krishna, K.Hussain Reddy, G.H.Philip

Mixed ligand complexes of copper(II)with salicyladoxime (SAO), 2-hydroxy acetophenone oxime (HAO) as primary ligands and pyridine(Py), imidazole (Im) as secondary ligands have been synthesized and characterized by molar conductivity,magneticmoments, electronic, IR and ESR spectral data. Cyclic voltammetric studies show quasi-reversible reduction attributable to Cu2+/ Cu+. The binding interactions between metal complexes and calf thymus DNA have been investigated by using UV-Visible titrations and cyclic voltammetry studies. The cleavage activity of complexes was carried out on double-stranded pBR322 circular plasmid DNAby using gel electrophoresis. All complexes show increased nuclease activity in the presence of oxidant (H2O2). The nuclease activity ofmixed ligand complexes are compared with that of the parent copper(II) complexes. Controlled experiments suggest that the complexes cleave DNA predominantly via an oxidative mechanism.