Electronic detection of dsDNA transition from helical to zipper conformation using graphene nanopores.

Mechanical manipulation of DNA by forced extension can lead double-stranded DNA (dsDNA) to structurally transform from a helical form to a linear zipper-like form. By employing classical molecular dynamics and quantum mechanical nonequilibrium Green's function-based transport simulations, we show the ability of graphene nanopores to discern different dsDNA conformations, in a helical to zipper transition, using transverse electronic conductance. In particular, conductance oscillations due to helical dsDNA vanish as dsDNA extends from a helical form to a zipper form while it is transported through the nanopore. The predicted ability to detect conformational changes in dsDNA via transverse electronic conductance can widen the potential use of graphene-based nanosensors for DNA detection.