title: A ruthenium(II) arene complex showing emission enhancement and photocleavage activity towards DNA from singlet and triplet excited states respectively.
abstract: The emission enhancement behavior and photocleavage activity of a ruthenium(II) arene complex, [(η(6)-p-cymene)Ru(dppn)(py)](2+) (1) (dppn = 4,5,9,16-tetraaza-dibenzo[a,c]naphthacene, py = pyridine), towards DNA were compared with [(η(6)-p-cymene)Ru(bpy)(py)](2+) (2), [Ru(bpy)2(dppz)](2+) (3) and [Ru(bpy)2(dppn)](2+) (4) (bpy = 2,2'-bipyridine, dppz = dipyrido-[3,2-a:2',3'-c]phenazine). It was found that 1 emits fluorescence from the dppn-based ligand-centered (LC) singlet excited state and generates singlet oxygen ((1)O2) from the dppn-based LC triplet excited state. As a result, 1 displays emission enhancement behavior and photocleavage activity towards DNA simultaneously. In contrast, 3 is the most classical DNA light switch but shows poor DNA photocleavage activity, while 4 is an efficient DNA photocleaver but cannot report DNA binding by luminescence enhancement. An increased cytotoxicity against human lung carcinoma cells A549 by about 10-fold was also observed for 1 upon visible light activation. These intriguing properties result from the unique combination of the Ru(II) arene and dppn subunits.
authors: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Yongjie
authors: Y
authors: Chen
authors: Wanhua
authors: W
authors: Lei
authors: Guoyu
authors: G
authors: Jiang
authors: Qianxiong
authors: Q
authors: Zhou
authors: Yuanjun
authors: Y
authors: Hou
authors: Chao
authors: C
authors: Li
authors: Baowen
authors: B
authors: Zhang
authors: Xuesong
authors: X
authors: Wang
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity; D000081007:Cymenes; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D053837:DNA Cleavage / Q000187:drug effects* / Q000528:radiation effects; D006801:Humans; D008027:Light; D039821:Monoterpenes / Q000737:chemistry; D010782:Photolysis; D012428:Ruthenium / Q000737:chemistry*; D026082:Singlet Oxygen / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D056831:Coordination Complexes; D000081007:Cymenes; D039821:Monoterpenes; D026082:Singlet Oxygen; C007210:4-cymene; D015082:2,2'-Dipyridyl; D012428:Ruthenium; D004247:DNA