Murali, S. ; Sastri, C. V. ; Maiya, Bhaskar G. (2002) New mixed ligand complexes of ruthenium(II) that incorporate a modified phenanthroline ligand: synthesis, spectral characterization and DNA binding Proceedings of the Indian Academy of Sciences - Chemical Sciences, 114 (4). pp. 403-415. ISSN 0253-4134
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Official URL: http://www.ias.ac.in/chemsci/Pdf-Aug2002/Pc3206.pd...
Related URL: http://dx.doi.org/10.1007/BF02703830
Abstract
The hexafluorophosphate and chloride salts of two ruthenium(II) complexes, viz. [Ru(phen)(ptzo)2]2 and [Ru(ptzo)3]2+, where ptzo = 1,10-phenanthrolino[5,6-e]1,2,4-triazine-3-one (ptzo) - a new modified phenanthroline (phen) ligand, have been synthesised. These complexes have been characterised by infrared, UV-Vis, steady-state emission and1H NMR spectroscopic methods. Results of absorption and fluorescence titration as well as thermal denaturation studies reveal that both thebis- and tris-complexes of ptzo show moderately strong affinity for binding with calf thymus (CT) DNA with the binding constants being close to 105M-1 in each case. An intercalative mode of DNA binding has been suggested for both the complexes. Emission studies carried out in non-aqueous solvents and in aqueous media without DNA reveal that both [Ru(phen)(ptzo)2]2+ and [Ru(ptzo)3]2+ are weakly luminescent under these solution conditions. Successive addition of CT DNA to buffered aqueous solutions containing [Ru(phen)(ptzo)2]2+results in an enhancement of the emission. These results have been discussed in the light of the dependence of the structure-specific deactivation processes of the MLCT state of the metallo-intercalator with the characteristic features of its DNA interaction. In doing so, attempts have been made to compare and contrast its properties with those of the analogous phenanthroline-based complexes including the ones reported by us previously.
Item Type: | Article |
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Source: | Copyright of this article belongs to Indian Academy of Sciences. |
Keywords: | Ruthenium(II) Complexes; Modified Phenanthroline Ligand; Spectroscopy; DNA Binding; Fluorescence Enhancement |
ID Code: | 32229 |
Deposited On: | 31 Mar 2011 10:01 |
Last Modified: | 17 May 2016 15:01 |
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