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Title: First-principles transversal DNA conductance deconstructed

Abstract

First-principles calculation of the transverse conductance across DNA fragments placed between gold nanoelectrodes, reveals that such conductance describes electron tunneling that depends critically on geometrical rather than electronic-structure properties. By factoring the first-principles result into two simple and approximately independent tunneling factors, we show that the conductances of the A, C, G, and T fragments differ only because of their sizes: the larger is the DNA base, the smaller is the distance that separates the electrode from the corresponding molecule, and the larger is its conductance. Because the geometrical factors are difficult to control in an experiment, the DC-current measurements across DNA may not be a convenient approach to DNA sequencing.

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Nanophase Materials Sciences
Sponsoring Org.:
Work for Others (WFO); USDOE Office of Science (SC)
OSTI Identifier:
1003335
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biophysical Journal; Journal Volume: 91; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; DNA; DNA SEQUENCING; ELECTRODES; ELECTRONIC STRUCTURE; ELECTRONS; GOLD; TUNNELING

Citation Formats

Zhang, Xiaoguang, Krstic, Predrag, Zikic, Radomir, Wells, Jack C, and Fuentes-Cabrera, Miguel A. First-principles transversal DNA conductance deconstructed. United States: N. p., 2006. Web. doi:10.1529/biophysj.106.085548.
Zhang, Xiaoguang, Krstic, Predrag, Zikic, Radomir, Wells, Jack C, & Fuentes-Cabrera, Miguel A. First-principles transversal DNA conductance deconstructed. United States. doi:10.1529/biophysj.106.085548.
Zhang, Xiaoguang, Krstic, Predrag, Zikic, Radomir, Wells, Jack C, and Fuentes-Cabrera, Miguel A. Sun . "First-principles transversal DNA conductance deconstructed". United States. doi:10.1529/biophysj.106.085548.
@article{osti_1003335,
title = {First-principles transversal DNA conductance deconstructed},
author = {Zhang, Xiaoguang and Krstic, Predrag and Zikic, Radomir and Wells, Jack C and Fuentes-Cabrera, Miguel A},
abstractNote = {First-principles calculation of the transverse conductance across DNA fragments placed between gold nanoelectrodes, reveals that such conductance describes electron tunneling that depends critically on geometrical rather than electronic-structure properties. By factoring the first-principles result into two simple and approximately independent tunneling factors, we show that the conductances of the A, C, G, and T fragments differ only because of their sizes: the larger is the DNA base, the smaller is the distance that separates the electrode from the corresponding molecule, and the larger is its conductance. Because the geometrical factors are difficult to control in an experiment, the DC-current measurements across DNA may not be a convenient approach to DNA sequencing.},
doi = {10.1529/biophysj.106.085548},
journal = {Biophysical Journal},
number = 1,
volume = 91,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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