Probing Electrical Properties of oriented DNA by conducting probe AFM
L.T. Cai*, H.Tabata and T.Kawai
Kawai Lab., ISIR-Sanken, Osaka University,
Ibaraki, Osaka 567-0047, Japan
This is an abstract
for a presentation given at the
Eighth
Foresight Conference on Molecular Nanotechnology.
There will be a link from here to the full article when it is
available on the web.
DNA is an important and promising molecule, not only due to its genetic function, but also as a molecular scaffold for nanotechnology and nanostructure. DNA has the special double helix structure with p-electron cores of well-stacking bases, which may be a good candidate for long-distance(e.g., 200Å) and one-dimensional charge transport. These investigations have significant implications for the study of DNA damage and repair in biological systems, the application of DNA in electronic devices and DNA-based electrochemical biosensors. The nature of this electronic interaction is vigorously debated and dependent on the base-sequence, dynamic structure and base stacking, etc.
Herein we report the direct measurements of electrical characteristics of DNA bundles and single DNA molecule, i.e. polyd(A)-polyd(T) and polyd(G)-polyd(C). Three different methods have been applied for the stretching and alignment of DNA on the freshly cleaved mica or modified-mica surface by APS and Mg ions. A gold electrode is fabricated on DNA/mica surface by shadow-mask deposition in high vacuum. The electrical properties of DNA are measured using an AFM equipped with a gold-coated conductive tip under vacuum.
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| Fig.1. Three elongated polyd(A)-polyd(T) molecules attached on gold electrode. |
*Corresponding Address:
Lintao Cai
Kawai Lab., ISIR-Sanken, Osaka University
8-1 Mihogaoka,
Ibaraki, Osaka 567-0047, Japan
Email: [email protected]
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