Electrical detection of Hachimoji nucleobases via a nanopore device incorporated in a graphene/h-BN heterostructure*

Sold-state nanopores based on 2D materials have been proposed as a candidate for next generation sequencing (NGS) to achieve high throughput, label-free DNA and protein sequencing at low costs. A recent endeavor in synthetic biology resulted in the creation of stable DNA/RNA systems based on 8 (`hachi`) letter (`moji`) building blocks (i.e. 4 synthetic and 4 natural nucleobases) [1]. Although mutations and methylations of the natural nucleobases have been extensively investigated, synthetic nucleobases reported in the hachimoji system remain unexplored with such NGS methods. Hence in this talk, we propose a computational study based on density functional theory and non-equilibrium Green’s function formalism, to unravel the electrical read-out of synthetic and natural nucleobases. To this end, we propose a hybrid 2D nanopore formed in a graphene nanorod embedded within hexagonal boron nitride to perform the electrical read. We will go on to show that the proposed hybrid 2D nanopore can qualitatively discriminate natural and synthetic nucleobases.
[1] Hoshika et al., Hachimoji DNA and RNA: A genetic system with eight building blocks, Science 363, 884 (2019)