The layer impact of DNA translocation through graphene nanopores

TL;DR

This study uses molecular dynamics simulations to explore how the number of graphene layers affects DNA translocation through nanopores, revealing that layer thickness influences ionic conductance, translocation probability, and speed.

Contribution

It provides new insights into the layer-dependent effects on DNA translocation dynamics in graphene nanopores, which was not previously well understood.

Findings

Ionic conductance varies with graphene layer number.

DNA translocation probability depends on nanopore thickness.

Bilayer graphene slows DNA translocation more than monolayer.

Abstract

Graphene nanopore based sensor devices are exhibiting the great potential for the detection of DNA. To understand the fundamental aspects of DNA translocating through a graphene nanopore, in this work, molecular dynamics (MD) simulations and potential of mean force (PMF) calculations were carried out to investigate the layer impact of small graphene nanopore (2 nm-3 nm) to DNA translocation. It was observed that the ionic conductance was sensitive to graphene layer of open-nanopores, the probability for DNA translocation through graphene nanopore was related with the thickness of graphene nanopores. MD simulations showed that DNA translocation time was most sensitive to the thickness of graphene nanopore for a 2.4 nm aperture, and the observed free energy barrier of PMFs and the profile change revealed the increased retardation of DNA translocation through bilayer graphene nanopore as compared to monolayer graphene nanopore.