DNA conductance modulation via aptamer binding

Abstract

The electronic properties of DNA make it an attractive candidate for applications in biosensing and molecular electronics. One approach to utilizing DNA in these fields involves binding molecules, such as aptamers, to control DNA's electrical conductance. By combining molecular dynamics simulations and density functional theory with Green's function-based charge transport calculations, we gain insights into aptamer induced structural realignment of DNA base pairs near the binding site. We find that this structural realignment enhances the electronic coupling, creating a conductive path near the highest occupied molecular orbital. This interaction results in a significant modulation of conductance by at least an order of magnitude compared to the dsDNA without the aptamer. We anticipate that our findings will promote the development of DNA-aptamer complexes for use in molecular electronics and biosensing applications.