Nanogallery
Nanogallery
TODAY DECEMBER 12, 2018

Search for DNA electrical conductance

Electrostatic trapping method illustrated in the previous picture has been applied to insert a few DNA molecules into the gap between two Pt electrodes. This setup is illustrated in the figure. Thus it was possible to test the electrical properties of DNA
DNA insert into a nanodevice acts as a semiconductor.
Electrostatic trapping technique has been used to insert a few DNA molecules into the gap between two Pt electrodes as is illustrated in the picture. Thus it was possible to test the electrical properties of DNA. The measurements suggest that the DNA conductance is similar to that of a large band gap semiconductor. In the experiment, the electrodes were separated by just about 8 nm. The 10-nm-long DNA double-helix links the electrodes and provides a path for the electrical current. It was suggested that the DNA conductance is due to the fact that each electron assumes a wavefunctions that is a superposition of many localized states, called orbitals. Although each orbital belongs to some particular base of the DNA, each electron has no definite position and can by visualized as a cloud spread over the entire DNA molecule. Since the molecule is not too long in these experiments, electrons can assume such sates that have a position uncertainty at least as large as the length of the DNA. By the Heisenberg Uncertainty Principle, such electrons can have a quite definite momentum and thus contribute significantly to the net electrical current flowing along the molecules. This explains why the DNA molecule can have a nonzero electrical conductance.


1. D. Porath, A. Bezryadin, S. de Vries, and C. Dekker, "Direct measurements of electrical transport through DNA molecules," Nature 403, 635638, 2000.

Carbon nanotubes are deposited in solution onto the substrate. The nanotubes are allowed to settle and stick to the surface of the substrate.
Nanowerk Nanotechnology Portal
http://www.nanowerk.com

Nanohedron
http://www.nanohedron.com

Biomolecules
http://perso.curie.fr/Simon.Sc..


Nano-news | Nanosuperconductors | Nanofabrication | Nanophenomena | Journals | Web directory | contacts

20042012 Copyright by Nanogallery.info
Design by UpMrk