Synthesis, characterization, and DNA binding, photocleavage, cytotoxicity, cellular uptake, apoptosis, and on-off light switching studies of Ru(II) mixed-ligand complexes containing 7-fluorodipyrido[3,2-a:2',3'-c]phenazine.

Four new ruthenium(II) polypyridyl complexes-[Ru(phen)2(7-F-dppz)](2+) (7-F-dppz is 7-fluorodipyrido[3,2-a:2',3'-c]phenazine, phen is 1,10-phenanthroline), [Ru(bpy)2(7-F-dppz)](2+)(2) (bpy is 2,2'-bipyridine), [Ru(dmb)2(7-F-dppz)](2+) (dmb is 4,4'-dimethyl-2,2'-bipyridine), and [Ru(hdpa)2(7-F-dppz)](2+) (hdpa is 2,2'-dipyridylamine)-have been synthesized and characterized. Their DNA binding behavior has been explored by various spectroscopic titrations and viscosity measurements, which indicated that all the complexes bind to calf thymus DNA by means of intercalation with different binding strengths. The light switching properties of these complexes have been evaluated, and their antimicrobial activities have been investigated.