DNA-binding and photocleavage studies of ruthenium(II) complexes containing asymmetric intercalative ligand

Spectrochim Acta A Mol Biomol Spectrosc. 2012 Feb:86:554-61. doi: 10.1016/j.saa.2011.11.014. Epub 2011 Nov 18.

Abstract

A novel asymmetric ligand 2-(pyridine-2-yl)-1-H-imidazo[4,5-i]dibenzo[2,3-a:2',3'-c]phenazine (pidbp) and its ruthenium complexes [Ru(L)(2)(pidbp)](2+) (L=bpy (2, 2'- bipyridine), phen (1, 10 - phenanthroline)), have been synthesized and characterized by elemental analysis, ES-MS, (1)H NMR. Various methods support the conclusion that both Ru(II) complexes can intercalate into DNA base pairs. Complex [Ru(bpy)(2)(pidbp)](2+)4 exhibits its DNA "molecular light switch" properties. Furthermore, the two complexes are efficient DNA-photocleavers under irradiation at 365 nm, and complex 5 exhibits a stronger DNA-photocleavage efficiency than complex 4. The mechanism of DNA cleavage is an oxidative process by generating singlet oxygen.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorption / radiation effects
  • Coordination Complexes / chemical synthesis
  • Coordination Complexes / chemistry
  • Coordination Complexes / metabolism*
  • DNA / metabolism*
  • DNA Cleavage / radiation effects*
  • Electrons
  • Electrophoresis, Agar Gel
  • Ethidium / chemistry
  • Intercalating Agents / chemistry
  • Intercalating Agents / metabolism*
  • Ligands
  • Light
  • Plasmids / metabolism
  • Ruthenium / chemistry
  • Ruthenium / metabolism*
  • Spectrometry, Fluorescence
  • Titrimetry
  • Viscosity / radiation effects

Substances

  • Coordination Complexes
  • Intercalating Agents
  • Ligands
  • Ruthenium
  • DNA
  • Ethidium