Electrochemical scanning tunneling microscope imaging of self-assembled monolayer of double-stranded DNA on Au(111).
Self-assembled monolayer of a double-stranded DNA, which was formed by a 20-nt 5'-thiol-modified oligonucleotide at the interface of Au(111)/solution, has been imaged and studied with electrochemical scanning tunneling microscopy (ECSTM). The results showed that the preferred directions of the adsorbed DNA were <110> and <112>. The measured width of the DNA stripes was 0.95 +/- 0.02 nm, which was consistent with the width of dsDNA base pairs. The contour of DNA in the STM image consisted of a series of blobs, which were due to the anchoring of the bases to the substrate along the dsDNA chain. The imaging of a large-scale array of DNA lying flat on the substrate offers a convenient method for the further application of high-resolution STM to the study of the interaction between DNA and a variety of molecules.
Yang
Guang-Zheng
GZ
Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
Ling
Lian-Sheng
LS
Wan
Li-Jun
LJ
Fang
Xiao-Hong
XH
Bai
Chun-Li
CL
D001482:Base Composition; D004247:DNA / Q000737:chemistry / Q000648:ultrastructure*; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D016252:Microscopy, Scanning Tunneling / Q000379:methods*; D036103:Nanotechnology / Q000379:methods*; D009690:Nucleic Acid Conformation
D006046:Gold; D004247:DNA