Perspectives of graphene-nucleotide complexes for the development of new bioelectronics devices

摘要

The purpose of this work is to study the physical phenomena that arise during contact of DNA nucleotides with a graphene substrate, and the numerical evaluation of the electrically conductive properties of graphene-nucleotide complexes. As a graphene substrate we considered graphene nanoribbons of armchair and zigzag type. We investigated changes in the atomic structure of the graphene-nucleotide complexes. Such characteristics of the complexes as charge redistribution, electron transmission functions, electrical conductivity and current-voltage characteristic were calculated using Nonequilibrium Green's function (NGF) matrices method. In order to calculate the electrical conductivity we constructed a model, where semi-infinite graphene sheets with the zigzag and armchair edges acted as electrodes, respectively. The search for the equilibrium configuration of graphene-nucleotide complexe was carried out by the method of relaxation scanning of the multi-well potential of the nucleotide interaction energy with a carbon object. Analysis of the calculated resistances and current-voltage characteristic showed that the most suitable for biosensorics are graphene nanoribbons of the zigzag type.