title: Tuning the cellular uptake properties of luminescent heterobimetallic iridium(III)-ruthenium(II) DNA imaging probes.
abstract: The synthesis of two new luminescent dinuclear Ir(III)-Ru(II) complexes containing tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]phenazine (tpphz) as the bridging ligand is reported. Unlike many other complexes incorporating cyclometalated Ir(III) moieties, these complexes display good water solubility, allowing the first cell-based study on Ir(III)-Ru(II) bioprobes to be carried out. Photophysical studies indicate that emission from each complex is from a Ru(II) excited state and both complexes display significant in vitro DNA-binding affinities. Cellular studies show that each complex is rapidly internalised by HeLa cells, in which they function as luminescent nuclear DNA-imaging agents for confocal microscopy. Furthermore, the uptake and nuclear targeting properties of the complex incorporating cyclometalating 2-(4-fluorophenyl)pyridine ligands around its Ir(III) centre is enhanced in comparison to the non-fluorinated analogue, indicating that fluorination may provide a route to promote cell uptake of transition-metal bioprobes.
authors.affiliation: Department of Chemistry, University of Sheffield, Sheffield, S3 9HJ (UK), Fax: (+44) 114-22-29436; Institute of Material Research and Engineering, A*STAR (Agency for Science, Technology and Research, Singapore).
authors.forename: Ashley
authors.initials: A
authors.lastname: Wragg
authors.forename: Martin R
authors.initials: MR
authors.lastname: Gill
authors.forename: David
authors.initials: D
authors.lastname: Turton
authors.forename: Harry
authors.initials: H
authors.lastname: Adams
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Roseveare
authors.forename: Carl
authors.initials: C
authors.lastname: Smythe
authors.forename: Xiaodi
authors.initials: X
authors.lastname: Su
authors.forename: Jim A
authors.initials: JA
authors.lastname: Thomas
mesh_terms: D002463:Cell Membrane Permeability; D056831:Coordination Complexes / Q000737:chemistry / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D015342:DNA Probes / Q000737:chemistry / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007495:Iridium / Q000737:chemistry / Q000378:metabolism*; D049449:Luminescence; D049408:Luminescent Agents / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D010619:Phenazines / Q000737:chemistry / Q000378:metabolism*; D012428:Ruthenium / Q000737:chemistry / Q000378:metabolism*
chemical_list: D056831:Coordination Complexes; D015342:DNA Probes; D049408:Luminescent Agents; D010619:Phenazines; D007495:Iridium; D012428:Ruthenium; D004247:DNA
keywords: DNA; bioprobes; iridium; luminescence; ruthenium