High Electronic Conductance through Double-Helix DNA Molecules with Fullerene Anchoring Groups

J Phys Chem A. 2017 Feb 16;121(6):1182-1188. doi: 10.1021/acs.jpca.7b00348. Epub 2017 Feb 3.

Abstract

Determining the mechanism of charge transport through native DNA remains a challenge as different factors such as measuring conditions, molecule conformations, and choice of technique can significantly affect the final results. In this contribution, we have used a new approach to measure current flowing through isolated double-stranded DNA molecules, using fullerene groups to anchor the DNA to a gold substrate. Measurements were performed at room temperature in an inert environment using a conductive AFM technique. It is shown that the π-stacked B-DNA structure is conserved on depositing the DNA. As a result, currents in the nanoampere range were obtained for voltages ranging between ±1 V. These experimental results are supported by a theoretical model that suggests that a multistep hopping mechanism between delocalized domains is responsible for the long-range current flow through this specific type of DNA.

MeSH terms

  • DNA, B-Form / chemistry*
  • Electric Conductivity
  • Fullerenes / chemistry*
  • Models, Chemical
  • Nanowires / chemistry
  • Nucleic Acid Conformation

Substances

  • DNA, B-Form
  • Fullerenes