Center for Computational Micro and Nanoelectronics, Faculty of Electrical Engineering, K. N. Toosi University of Technology, 16317-14191 Tehran, Iran.
Theoretische Chemie, Universität Hannover, Callinstr. 3A, 30167 Hannover, Germany.
Phys Chem Chem Phys. 2021 Nov 17;23(44):25126-25135. doi: 10.1039/d1cp03597e.
The in-plane heterostructure of graphene and h-BN has unique physical and electrical characteristics, which can be exploited for single-molecule DNA sequencing. On this account, we propose a nanostructure based on a nanopore in graphene/h-BN/graphene heterostructures as a viable approach for in-plane electrical detection. The insulating h-BN layer changes the charge transport to the quantum tunneling regime, which is very sensitive to the electrostatic interactions induced by nucleotides during their translocation through the nanopore. Density functional theory (DFT) is utilized to study the membrane/nanopore interactions as well as their interactions with different nucleotides (dAMP, dGMP, dCMP, and dTMP). The results indicate that the nucleotides show stronger interactions with nanopores in h-BN rather than nanopores in pristine graphene. For the calculation of electronic transport, non-equilibrium Green's function (NEGF) formalism at the first principles level is employed. The in-plane currents at different applied voltages are calculated in the presence of different nucleotides in the nanopore. The sensitivity of the proposed nanostructure towards different nucleotides is measured based on the current modulation induced by each nucleotide. The graphene/h-BN/graphene heterostructure shows higher sensitivity toward different nucleotides compared to a similar structure consisting of pristine graphene and can be considered as a promising candidate for DNA sequencing applications.
石墨烯和 h-BN 的面内异质结构具有独特的物理和电学特性，可用于单分子 DNA 测序。有鉴于此，我们提出了一种基于石墨烯/ h-BN/ 石墨烯异质结构中纳米孔的纳米结构，作为面内电检测的可行方法。绝缘的 h-BN 层将电荷输运改变为量子隧穿模式，这对核苷酸在通过纳米孔迁移时引起的静电相互作用非常敏感。我们利用密度泛函理论（DFT）研究了膜/纳米孔相互作用及其与不同核苷酸（dAMP、dGMP、dCMP 和 dTMP）的相互作用。结果表明，与原始石墨烯中的纳米孔相比，核苷酸与 h-BN 中的纳米孔具有更强的相互作用。对于电子输运的计算，在第一性原理水平上采用非平衡格林函数（NEGF）形式。在纳米孔中存在不同核苷酸的情况下，计算了不同外加电压下的面内电流。基于每个核苷酸引起的电流调制来测量所提出的纳米结构对不同核苷酸的灵敏度。与由原始石墨烯组成的类似结构相比，石墨烯/ h-BN/ 石墨烯异质结构对不同核苷酸具有更高的灵敏度，可被视为 DNA 测序应用的有前途的候选者。
