Voltammetric detection of the DNA interaction with copper complex compounds and damage to DNA

Binding reactions of copper(II) complexes of 1,10-phenanthroline (phen) and tetraaza macrocyclic ligand TAAB with calf thymus DNA have been investigat ed voltammetrically at bare and DNA modified glassy carbon electrodes. The values of binding constant, binding site size, ratio of binding constants f or the reduced and oxidized copper complex forms as well as information on the electrostatic and intercalative binding modes were obtained by solution and surface-based methods. The Cu(phen)S' complex mediates the dsDNA cleav age to a higher degree than Cu(TAAB)(2+) as indicated by the redox marker C o(phen)(3)(3+) and the anodic signal of the DNA base. A procedure for the d amage to DNA detection using dsDNA/GCE biosensor is proposed.