Effect of Noise on DNA Sequencing via Transverse Electronic Transport

TL;DR

This study models environmental noise effects on transverse electronic transport in DNA sequencing, finding that typical fluctuations do not significantly disrupt current signatures, thus supporting the method's robustness.

Contribution

The paper introduces a simple model analyzing environmental scattering effects on electronic DNA sequencing, showing current distributions are resilient to typical noise levels.

Findings

Environmental fluctuations have limited impact on current distributions.

Large scattering strengths significantly alter current signatures.

Transverse electronic transport remains viable for DNA sequencing despite noise.

Abstract

Previous theoretical studies have shown that measuring the transverse current across DNA strands while they translocate through a nanopore or channel may provide a statistically distinguishable signature of the DNA bases, and may thus allow for rapid DNA sequencing. However, fluctuations of the environment, such as ionic and DNA motion, introduce important scattering processes that may affect the viability of this approach to sequencing. To understand this issue, we have analyzed a simple model that captures the role of this complex environment in electronic dephasing and its ability to remove charge carriers from current-carrying states. We find that these effects do not strongly influence the current distributions due to the off-resonant nature of tunneling through the nucleotides - a result we expect to be a common feature of transport in molecular junctions. In particular, only large scattering strengths, as compared to the energetic gap between the molecular states and the Fermi level, significantly alter the form of the current distributions. Since this gap itself is quite large, the current distributions remain protected from this type of noise, further supporting the possibility of using transverse electronic transport measurements for DNA sequencing.