▎ 摘　　要

First-principles calculations were applied to design and study the electron transport behavior of a biomolecular sensor with graphene-based electrodes. It is shown that the designed biosensor is capable of distinguishing different nucleotide molecules such as cytosine, methylcytosine, and hydroxymethylcytosine. The current was seen to change by nearly one order of magnitude, while molecules passed through the device individually. The resolution capacity of the present device was primarily determined by the interactions and specific configurations of two adjacent single-stranded desoxyribonucleic acid (DNA) molecules and their specific configurations. This graphene-based biosensor was proved to be effective and efficient in detecting and distinguishing different DNA molecules, which provides a new potential method to pinpoint exactly varietal base molecules in DNA chains for the genetic information.