Base-Dependent Competitive Adsorption of Single-Stranded DNA on Gold
H Y. Kimura-Suda, D Y. Petrovykh, Michael J. Tarlov, L J. Whitman
Aqueous solutions of single-stranded DNA probes (ssDNA) are widely used with gold surfaces in current biotechnology and emerging nanotechnology applications. Although recent studies have shown that different DNA bases interact differentlywith gold surfaces, competitive interactions among the bases which will occur in most practical applications have not been systematically addressed. Here we examine room-temperature adsorption of the four DNA bases onto polycrystalline gold films, including competitive adsorption between all possible pairs ofunmodified homo-oligonucleotides. We find the homo-oligonucleotides adsorb with a base-dependent affinity thymine (T) < guanine (G) cytosine (C) < adenine (A). In competitive experiments, adsorption of poly(dA) strongly dominates over other oligonucleotides. The adsorption affinity of the nucleotide dA to gold is so great that it allows poly(dA) to compete effectively against adsorption of a thiolatedssDNA, and even forces the dissociation of dA.dT duplexes from solution.
, Petrovykh, D.
, Tarlov, M.
and Whitman, L.
Base-Dependent Competitive Adsorption of Single-Stranded DNA on Gold, Journal of the American Chemical Society
(Accessed December 4, 2023)