Presentation day

Wednesday  8:10 PM

 

TITLE

Fabrication of 3-D nanodot array using Dps-DNA self-assembly

 

Abstract

In the field of electric devices, a 3-D nanodots array has been desired as a nanostructure
for various kinds of devices such as memory devices, thermoelectric transducers, solar cells and spintronic
devices. However, conventional semiconductor fabrication processes e.g. a vacuum process at hightemperature
has problems of a high energy consumption and a low throughput. Nano-fabrication processes
based on self-assembly of protein have attracted much attention in terms of both a low energy consumption
and a low environmental stress. Especially, Dps (DNA binding protein form starved cells) has been studied
in the field of bio-nanotechnology since Dps has unique features that constrict a 3-D nanostructure. Dps
from Escherichia coli is a 9 nm cage-shaped protein with a 4 nm hollow core. Dps creates a nanodot (<4
nm) in its hollow cavity by biomineralization. When bacteria suffering from starving produce Dps protein for
a generic defense strategy, Dps crystallizes with DNA to protect DNA against varied environmental stress.
The protection makes a 3-D structure of nanodots accommodated by Dps. Because the outer proteins
whose size is defined by genetic codes separate each FeOx nanodots, the nanostructure is uniform. In
order to establish a nano-construction process using Dps-DNA self-assembly, further investigations on Dps
-DNA self-assembly in vitro has been required. In this study, we proposed to control Dps-DNA
crystallization by changing electrical interactions. We found that the self-assembly control can be operated
by changing buffer concentration that effects electrical interactions gently. The formation of FeOx
superlattice by the self-assembly was reveled from TEM observation.