Stable and reproducible electronic conduction through DNA molecular junctions

Ajit K. Mahapatro, Purdue University - Main Campus
Gil Lee, Purdue University - Main Campus
Kyung J. Jeong, Purdue University - Main Campus
David B. Janes, Purdue University

Date of this Version



DOI: 10.1063/1.3186056

This document has been peer-reviewed.



This letter presents the observation of stable and reproducible electronic conduction through double stranded (ds) DNA molecules in a nominally dry state. Stable conduction was realized by immobilizing 15 base-pair guanine:cytosine rich dsDNA within gold nanogap junctions, stabilizing the dsDNA with a polycation, and characterizing in nitrogen. In air, the current levels decrease with successive voltage scans likely due to oxidation of the guanine bases under bias. In nitrogen, reproducible current-voltage traces are observed and the current levels at specific bias points are stable with time. The stability allows comprehensive electrical studies and could enable conductance-based DNA sensors.


Nanoscience and Nanotechnology