New insights in the DNA-[Cr(phen)2(dppz)]3+ binding and photocleavage properties by the complex with an intercalating ligand

J. TONEATTO; R. A. BOERO; G. LORENZATTI; ANA M. CABANILLAS; G. A. ARGUELLO

Elsevier

Lugar: UK; Año: 2010 vol. 104 p. 697 - 697

font size="3" face="Cambria"> Abstract: Chromium(III) complex [Cr(phen)2(dppz)]3+, (dppz = dipyridophenazine, phen = 1,10- phenanthroline), has been found to bind strongly to double strand oligonucleotides (ds-oligo) and plasmid DNA with a intrinsic DNA binding constants, Kb, of (3.9 ± 0.3) x105 M-1 and (1.1 ± 0.1) x105 M-1, respectively. The binding properties to DNA were investigated by UV-visible and electrophoretic studies. UV-Vis absorption data provide clearly that the Chromium(III) complex interacts with DNA intercalatively. Competitive binding experiments show that the enhancement in the emission intensity of ethidium bromide (EthBr) in the presence of DNA was quenched by [Cr(phen)2(dppz)]3+, indicating that the Cr(III) complex displaces EthBr from its binding site in plasmid DNA. Moreo