Base-Dependent Competitive Adsorption of Single-Stranded DNA on Gold
Abstract
Single-stranded DNA probes (ssDNA) immobilized on gold surfaces are a common element in many biotechnology and nanotechnology applications. Although recent studies have shown that different DNA bases and homo-oligonucleotides interact differently with Au 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 homo-oligonucleotides onto polycrystalline Au films, including competitive adsorption between all possible pairs of such unmodified oligomers. Homo-oligonucleotides serve as a model system that allows us to systematically study the base- and length dependence of ssDNA-Au interactions, while maintaining most properties of practical ssDNA probes. We characterize the adsorption ex-situ using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS), two methods that together provide unambiguous spectral signatures of the different bases and allow absolute surface densities to be determined.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2003
- Accession Number
- ADA481143
Entities
People
- Dmitri Y. Petrovykh
- Hiromi Kimura-suda
- Llyod J. Whitman
- Michael J. Tarlov
Organizations
- National Institute of Standards and Technology