Synthetic Hachimoji DNA Sequencing with Graphene Nanodevice

TL;DR

This study explores quantum interference effects in synthetic Hachimoji DNA within graphene nanodevices, revealing significant conductance variations that could enable precise DNA sequencing.

Contribution

It demonstrates the potential of quantum interference effects in graphene nanodevices for distinguishing nucleobases in synthetic DNA sequencing.

Findings

Conductance varies by 2-5 orders of magnitude with nucleobase rotation.

Distinct current-voltage signatures for different nucleobases.

Quantum interference effects influence conductance and tunneling current.

Abstract

Based on combined density functional theory and nonequilibrium Greens function quantum transport studies, we have demonstrated quantum interference effects on the transverse conductance of Hachimoji synthetic nucleic acids placed between the oxygen-terminated zigzag graphene nanoribbon nanoelectrodes. We theorize that the QI effect could be well preserved in pi-pi coupling between a nucleobase molecule and the carbon-based nanoelectrode. Our study indicates that QI effects such as anti-resonance or Fano-resonance that affect the variation of transverse conductance depending on the nucleobase conformation. Further, a variation of up to 2-5 orders of magnitude is observed in the conductance upon rotation for all the nucleobases. The current-voltage characteristics results suggest a distinct variation in the electronic tunnelling current across the proposed nanogap device for all the five nucleobases with the applied bias voltage. The different rotation angles keep the distinct feature of the nucleobases in both transverse conductance and tunnelling current features. Both features could be utilized in an accurate synthetic DNA sequencing device.