ISSN:
0006-3525
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The binding of tris(2,2′-bipyridyl)ruthenium(II) cations [Ru(bpy)2+3] with single- and double-stranded (ss and ds) DNA, and the polynucleotides poly(A), poly(C), poly(G), poly(I), poly(I) · poly(C), and poly(U), was studied in aqueous solution. Steady-state electrical conductivity measurements with the polynucleotides, ssDNA, and dsDNA reveal that approximately three nucleotides offer one binding site. This may be compared with the ratio [nucleotide]/[Mg2+] of 2.4 : 1 for dsDNA. After laser excitation (353 nm), the luminescence of Ru(bpy)2+3 bound to nucleic acids shows two decay components. The contribution of the fast component, which is interpreted as resulting from quenching processes of the absorbed ruthenium complex, exhibits a maximum with increasing [nucleotide]/[Ru(bpy)2+3] at a ratio of about three to one. Bound Ru(bpy)2+3 can be released from the strand by addition of NaClO4 [half-concentration: 2.5 and ≤ 10 mM for poly(U) and dsDNA, respectively].
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bip.360260203
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