Enhanced DNA Sequencing Performance Through Edge- Hydrogen ati on of Graphene Electrodes

摘要

The use of graphene electrodes with hydrogenated edges for solid-state nanopore-based DNA sequencing is proposed, and molecular dynamics simulations in conjunction with electronic transport calculations are performed to explore the potential merits of this idea. The results of the investigation show that, compared to the unhydrogenated system, edge-hydrogenated graphene electrodes facilitate the temporary formation of H-bonds with suitable atomic sites in the translocating DNA molecule. As a consequence, the average conductivity is drastically raised by about 3 orders of magnitude while exhibiting significantly reduced statistical variance. Furthermore, the effect of the distance between opposing electrodes is investigated and two regimes identified: for narrow electrode separation, the mere hindrance due to the presence of protruding hydrogen atoms in the nanopore is deemed more important, while for wider electrode separation, the formation of H-bonds becomes the dominant effect. Based on these findings, it is concluded that hydrogenation of graphene electrode edges represents a promising approach to reduce the translocation speed of DNA through the nanopore and substantially improve the accuracy of the measurement process for whole-genome sequencing.