Super-sensitive Molecule-hugging Graphene Nanopores

TL;DR

This paper demonstrates that graphene nanopores exhibit high sensitivity to small changes in DNA diameter, making them promising for DNA sequencing with excellent resolution and robustness compared to protein nanopores.

Contribution

The study provides experimental evidence of high sensitivity in graphene nanopores tailored to DNA diameters, advancing nanopore-based sequencing technology.

Findings

Large sensitivities (0.5 nA/A) achieved with tailored graphene nanopores

Graphene nanopores can distinguish small diameter changes in DNA

Potential for graphene nanopores to rival protein nanopores in sequencing

Abstract

Longitudinal resolution and lateral sensitivity are decisive characteristics that determine the suitability of a nanopore sensor for sequencing a strand of DNA as well as other important polymers. Previous modeling of DNA induced ionic current blockades in single atom thick graphene nanopores has shown these nanopores to have sufficient longitudinal resolution to distinguish individual nucleobases along the length of a DNA molecule. Here we experimentally focus on the sensitivity to small changes in DNA diameter that can be discerned with graphene nanopores. We show that remarkably large sensitivities (0.5 nA/A)are obtained when the nanopore is tailored to have a diameter close to that of the polymer of interest. Our results have been obtained with double-stranded DNA (dsDNA). Smaller graphene nanopores that can be tuned to the diameter of single-stranded DNA (ssDNA) for sequencing have only recently been demonstrated. Our results indicate that nanopore sensors based on such pores will provide excellent resolution and base discrimination, and will be robust competitors to protein nanopores that have recently demonstrated sequencing capability.