First-principle insights into the non-covalent interaction between nucleotide bases and flat nanocarbon: Graphene vs graphdiyne

Abstract

Carbon-based devices are the most promising candidate for rapid and inexpensive development of biological identification and detection. The key factors to design and modulate the devices performances is heavily dependent on the understanding for non-covalent interaction between nucleotide bases (NBs) and carbon substrates for deoxyribo nucleic acid sequencing. This work is aimed to reveal non-covalent interaction between NBs and two flat nano‑carbon, graphene (GR) and graphdiyne (GDY) by density functional theory calculations. For all the complexes studied here, GDY or GR nano-flakes almost maintain the pristine structures after NBs absorbed and Van der Waals force dominates the intermolecular interaction of the adsorption. The binding energies between NBs and GR (or GDY) are all negative. However, the binding force between NBs and GR is stronger than that between NBs and GDY. Deformation energies of both NBs and the adsorbent are small, and the interaction energies are more important for the binding process compared with deformation. Based on energy decomposition analysis and reduced density gradient, the interactions behavior of the adsorption could be well described directly from both quantitative description and intuitive characterization. It is found that dispersion energy occupied >50 % of the total interaction energy, dominating the adsorption for NBs onto surfaces of GR and GDY.