Absence of intrinsic electric conductivity in single dsDNA molecules

H Kleine; R Wilke; Ch Pelargus; K Rott; A Pühler; G Reiss; R Ros; D Anselmetti

doi:10.1016/j.jbiotec.2004.04.031

Absence of intrinsic electric conductivity in single dsDNA molecules

J Biotechnol. 2004 Aug 26;112(1-2):91-5. doi: 10.1016/j.jbiotec.2004.04.031.

Authors

H Kleine¹, R Wilke, Ch Pelargus, K Rott, A Pühler, G Reiss, R Ros, D Anselmetti

Affiliation

¹ Experimental Biophysics, Faculty of Physics, Bielefeld University, Universitätsstrasse 25, D-33615 Bielefeld, Germany.

PMID: 15288944
DOI: 10.1016/j.jbiotec.2004.04.031

Abstract

The intrinsic dc conductivity of long, individual lambda phage dsDNA molecules has been investigated by ultrasensitive low current-voltage-spectroscopy (IV) under ambient conditions and controlled low humidity inert gas atmosphere on microfabricated metal-insulator-metal gap structures. We found a strong dependence of the measured conductivity on the apparent humidity, which we attribute to capillary condensation of water to the immobilized DNA molecules, giving rise to additional ionic currents. Additional IV-spectroscopy experiments under controlled argon atmosphere always revealed a significant drop in electrical conductivity to 4 x 10(-15)AV(-1)microm(-1), indicating almost no considerable contribution of electrical long range charge transport.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacteriophage lambda / genetics*
DNA, Viral / analysis*
DNA, Viral / chemistry*
DNA, Viral / ultrastructure
Electric Conductivity
Electrochemistry / methods*
Electrodes*
Spectrum Analysis / methods*

Substances

DNA, Viral