Abstract
DNA has several characteristics such as complementation, self-replicating function, and self-assembly network formation. They are expected to be applied to development of bio-nano technologies. In addition, phosphoric groups in main chains of DNA have negative charges in aqueous solutions. In this study, self-assembled structures of poly(dA)-poly(dT) DNA on highly oriented pyrolytic graphite (HOPG) is investigated. It is not easy to fabricate self-assembled DNA networks on HOPG due to the negatively charged surfaces. We try to artificially control the behavior of DNA in the aqueous solution by applying electric voltages. Using an in-house experimental apparatus and an atomic force microscope (AFM), self-assembled networks are successfully observed on the HOPG surfaces. The concentration of the aqueous solution is set to 0.5 μM. Consequently, based on the Fourier analyses, it is found that peculiar structures of DNAs, e.g., hexagonal textures, are formed on the HOPG surfaces.
