Adsorption of calf thymus DNA on Au(110) studied by reflection anisotropy spectroscopy.
Reflection anisotropy spectroscopy (RAS) was used to investigate the adsorption of single-stranded (ss-) and double-stranded (ds-) calf thymus DNA on Au(110) in an electrochemical cell. Both types of DNA form ordered structures for electrode potentials in the range from +0.6 to -0.4 V. Both types of DNA desorb at -0.6 V and may start desorbing at lower negative potentials. When adsorbed at +0.6 V, both forms give rise to a similar RAS signal and adsorb through the phosphate groups. As the potential is reduced, the RAS intensity observed from ss-DNA increases to roughly twice that observed from ds-DNA, a result that is interpreted as due to a change in the adsorption of the ss-DNA from sites involving the phosphate groups to sites involving the bases.
Cuquerella
M Consuelo
MC
Department of Physics, Oliver Lodge Laboratory, and School of Biological Sciences, University of Liverpool, Liverpool L69 7ZE, United Kingdom.
Smith
Caroline I
CI
Fernig
David G
DG
Edwards
Clive
C
Weightman
Peter
P
D000327:Adsorption; D000818:Animals; D016880:Anisotropy; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D013057:Spectrum Analysis
D006046:Gold; D004247:DNA; C427203:calf thymus DNA