The role of surface charging during the coadsorption of mercaptohexanol to DNA layers on gold: direct observation of desorption and layer reorientation.
We study the coadsorption of mercaptohexanol onto preimmobilized oligonucleotide layers on gold. Monitoring the position of the DNA relative to the surface by optical means directly shows the mercaptohexanol-induced desorption of DNA and the reorientation of surface-tethered strands in situ and in real time. By simultaneously recording the electrochemical electrode potential, we are able to demonstrate that changes in the layer conformation are predominantly of electrostatic origin and can be reversed by applying external bias to the substrate.
Arinaga
K
K
Walter Schottky Institut, Technische Universitaet Muenchen, 85748 Garching, Germany. ari@jp.fujitsu.com
Rant
U
U
Tornow
M
M
Fujita
S
S
Abstreiter
G
G
Yokoyama
N
N
D000327:Adsorption; D001483:Base Sequence; D002232:Carbocyanines; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes; D006046:Gold; D000441:Hexanols / Q000737:chemistry*; D008422:Materials Testing; D055672:Static Electricity; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties
D002232:Carbocyanines; D020099:Coated Materials, Biocompatible; D005456:Fluorescent Dyes; D000441:Hexanols; D013438:Sulfhydryl Compounds; C089187:cyanine dye 3; D006046:Gold; D004247:DNA