Reaction–diffusion wave model for self-assembled network formation of poly(dA)·poly(dT) DNA on mica and HOPG surfaces

Abstract

Deoxyribonucleic acid (DNA) is a vital molecule for life since it contains genetic information. However, DNA has recently been reported to have unique properties that make it suitable for bionanoelectronic applications, such as the possibility of electrical conductivity and self-organisation. Self-assembled DNA network structures have been observed on several substrates, but the detailed self-assembly mechanism has yet to be determined. The present study investigates self-assembled structures of DNA both theoretically and experimentally. We developed a reaction–diffusion model and used it to investigate pattern formations observed by atomic force microscopy. The computational results qualitatively replicate the network patterns of DNA molecules based on a quantitative agreement with the surface size and timescale. The model can account for the effect of the DNA concentration on pattern formation. Furthermore, peculiar geometric patterns are simulated for mica and highly oriented pyrolytic graphite surfaces.

Keywords::

• DNA
• self-assembly
• reaction–diffusion wave
• pattern formation
• HOPG
• mica