Photoluminescence quenching/recovery kinetics of [Ru(bpy)2(tatp)]2+ and [Ru(bpy)2(dmtatp)]2+ intercalated within DNA by copper(II) ions and EDTA.
The quenching and recovery kinetics of photoluminescence of [Ru(bpy)(2)(tatp)](2+) (Ru1) and [Ru(bpy)(2)(dmtatp)](2+) (Ru2) intercalated within DNA (where bpy=2,2'-bipyridine, tatp=1,4,8,9-tetra-aza-triphenylene and dmtatp=2,3-dimethyl-1,4,8,9-tetra-aza-triphenylene) have been investigated by steady-state and time-resolved methods performed at various temperatures (293-333K). Two complexes Ru1 and Ru2 show a single-exponential luminescence decay with τ(Ru1)=246.0 ns and τ(Ru2)=513.5 ns, whose luminescence upon intercalating into DNA exhibits very consistent bi-exponential decay changes. The addition of Cu(2+) ions is found to dynamically quench the luminescence of both DNA-bound Ru(II) complexes, involving a spontaneous exothermic process. The sequential addition of EDTA can partially recover the luminescence quenched by Cu(2+), however depending on methyl substituents of the intercalative ligand. The chemical conversion and luminescence control mechanism of the two DNA-bound Ru(II) complexes is discussed in detail. The present results should be of value for better understanding chemical modulation of DNA-bound Ru(II) complexes as luminescence probes.
Key Laboratory of Technology on Electrochemical Energy Storage and Power Generation in Guangdong Universities, School of Chemistry and Environment, South China Normal University, Guangzhou, PR China.
Shibo
S
Ji
Miaojing
M
Chen
Guilian
G
Gan
Hong
H
Li
Weishan
W
Li
D000818:Animals; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry*; D007364:Intercalating Agents / Q000737:chemistry*; D007477:Ions; D007700:Kinetics; D049449:Luminescence; D009942:Organometallic Compounds / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013997:Time Factors
D007364:Intercalating Agents; D007477:Ions; D009942:Organometallic Compounds; D003300:Copper; D012428:Ruthenium; D004247:DNA; D004492:Edetic Acid