DNA-binding and photocleavage studies of mixed polypyridyl ruthenium(II) complexes with calf thymus DNA

Complexes [Ru(dmb)2(NMIP)]2+ (1) and [Ru(bpy)2(NMIP)]2+ (2) have been synthesized and characterized. The binding of these complexes to CT-DNA has been investigated with spectroscopic methods, viscosity and electrophoresis measurements. The experimental results indicate that both complexes could bind to DNA via partial intercalative from the minor/major groove. In addition, both complexes have been found to promote the single-stranded cleavage of plasmid pBR 322 DNA upon irradiation.