Effect of hydration on electrical conductivity of DNA duplex: Green’s function study combined with DFT

The electrical conductivity of DNA duplex is affected by many factors such as DNA base sequence, hydration of DNA duplex, connecting configuration between DNA duplex and electrodes, thermal fluctuation of DNA duplex structure. We here investigate the electrical conducting properties of DNA duplexes sandwiched between Au electrodes by molecular simulations using nonequilibrium Green’s function method coupled with density functional theory. The results reveal the dependence of electrical conductivity on DNA base sequence as well as hydration, which are in qualitative agreement with experiment. The present results indicate the important role played by hydrating water molecules in the electrical conductivity through DNA duplexes.