Singlet Oxygen-Mediated DNA Photocleavage with Ru(II) Polypyridyl Complexes
| Autor: | M. Emilia Jiménez-Hernández, Arantxa Hergueta-Bravo,†,‡, Guillermo Orellana, Francisco Montero, and Esther Oliveros |
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| Rok vydání: | 2002 |
| Předmět: |
Quenching (fluorescence)
Singlet oxygen Phenazine Cationic polymerization Photochemistry Binding constant Surfaces Coatings and Films Metal chemistry.chemical_compound chemistry Polynucleotide visual_art Agarose gel electrophoresis Materials Chemistry visual_art.visual_art_medium Physical and Theoretical Chemistry |
| Zdroj: | The Journal of Physical Chemistry B. 106:4010-4017 |
| ISSN: | 1520-5207 1520-6106 |
| Popis: | The efficiency of photosensitized DNA cleavage and quantum yields of singlet oxygen production (ΦΔ) have been determined for the metal complexes [Ru(bpy)2(ddz)]2+, [Ru(phen)2(ddz)]2+, [Ru(phen)3]2+, and [Ru(dsdp)3]4- (bpy = 2,2‘-bipyridine, ddz = dibenzo[h,j]dipyrido[3,2-a:2‘,3‘-c]phenazine, phen = 1,10-phenanthroline, and dsdp = 1,10-phenanthroline-4,7-diphenylsulfonate). ΦΔ values (0.19−0.52) have been measured in O2-saturated D2O solution, both in the absence and presence of DNA. Protection of the photoexcited Ru(II) complexes from O2 quenching imparted by the polynucleotide was evaluated from their emission lifetimes (0.13−3.7 μs) measured at three different O2 concentrations. Our results show the highest photocleavage efficiency for those sensitizers that display strong affinity for DNA (binding constant Kb > 106 M-1), despite their lower ΦΔ values (0.08−0.10 for the three cationic complexes vs 0.40 for the tris-dsdp, in H2O/air/DNA). Kinetic analysis (agarose gel electrophoresis) of the photocleavag... |
| Databáze: | OpenAIRE |
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