Photoinduced electron transfer between ruthenium complexes and nucleotides or DNA
نویسنده
چکیده
The quenching of the luminescence of Ru(TAP)++, Ru(HAT)z(bpyp+ (TAP = 1,4,5$-tetraazaphenanthrene; HAT = 1,4,5,8,9,12-hexaazatphenylene; bpy = 2,2'bipyridyl) and related oxidising complexes by DNA, polynucleotides, and purine nucleotides occurs by reductive electron transfer. Laser flash photolysis provides evidence for the formation of the reduced metal complex and the deprotonated nucleotide radical cation. This photo-oxidation leads to DNA strand-breaks and to the formation of covalent adducts with GMP or DNA. The adducts with RU(TAP)~~+ or Ru(HAT),(bpy)2+ are formed via a covalent bond between the C atom p to the coordinating N in the TAP or HAT ligand and the N2 of guanine.
منابع مشابه
Fast photoinduced electron transfer through DNA intercalation.
We report evidence for fast photoinduced electron transfer mediated by the DNA helix that requires metal complexes that are avid intercalators of DNA. Here the donor bis(phenanthroline)(dipyridophenazine)ruthenium(II) [Ru(phen)2dppz2+] and acceptor bis(9,10-phenanthrenequinone diimine)(phenanthroline)rhodium(III) [Rh(phi)2phen3+] intercalate into DNA with Kb > 10(6) M-1. Luminescence quenching ...
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