NEXAFS Characterization of DNA Components and Molecular-Orientation of Surface-Bound DNA Oligomers

Published

September 7, 2006

Author(s)

N T. Samuel, C H. Lee, L Gamble, Daniel A. Fischer, David G. Castner

Abstract

Single stranded DNA oligomers (ssDNA) immobilized onto solid surfaces forms the basis for several biotechnological applications such as DNA microarrays, affinity separations, and biosensors. The surface structure of the surface-bound oligomers is expected to significantly influence their biological activity and interactions with the environment. In this study near-edge x-ray absorption fine structure spectroscopy (NEXAFS) is used to characterize the components of DNA (nucleobases, nucleotides and nucleosides) and the orientation information of surface-based ssDNA. The k-edges of carbon, nitrogen and oxygen have spectra with features that are characteristic of the different chemical species present in the nucleobases of DNA. The effect of addition of the DNA sugar and phosphate components on the NEXAFS k-edge spectra was also investigated. The polarization-dependent nitrogen k-edge NEXAFS data show significant changes for different orientations of surface bound ssDNA. These results show NEXAFS is a powerful non-destructive technique for chemical and structural characterization of surface-bound DNA oligomers.

Citation

Journal of Electron Spectroscopy and Related Phenomena

Volume

152

Pub Type

Journals

Keywords

DNA, monolayers, NEXAFS, XPS

Citation

Samuel, N. , Lee, C. , Gamble, L. , Fischer, D. and Castner, D. (2006), NEXAFS Characterization of DNA Components and Molecular-Orientation of Surface-Bound DNA Oligomers, Journal of Electron Spectroscopy and Related Phenomena (Accessed December 14, 2024)