Effects of humidity and depurination on the charge transport in DNA films

We have investigated the humidity and depurination (creating apurinic sites) effects on the electrical conduction in the λ-DNA films at different relative humidities and depurination times. The DNA films were found to follow the polaron hopping model, and the polaron hopping distance turned out to decrease at the higher relative humidity, more water molecules supposedly being adsorbed on the film. The activation energy showed little dependence on the depurination time at the higher relative humidity, whereas at the lower humidity it increased sharply with increasing depurination time.