Visualization of periodic electric polarizability of helical nanofibers formed by self-assembly of nucleotide-bearing bolaamphiphiles and natural-source DNA as a template

Abstract

The possibility of fabricating DNA-based electronics has attracted considerable attention, but constructing robust, functional DNA nanowires on hard substrates has proven to be difficult. This paper describes the production of robust one-dimensional nanofibers by self-assembly of 1,18-nucleotide-bearing bolaamphiphiles templated by salmon sperm DNA. Electrostatic force microscopy measurements of the nanofibers on a highly oriented pyrolytic graphite substrate revealed that they showed electric polarizability that varied periodically with a pitch of 20–30 nm. Atomic force microscopy, gel electrophoresis, and circular dichroism spectroscopy suggested that the periodic polarizability was derived from right-handed helicity induced by the template DNA. Salmon sperm DNA itself did not show electric polarizability.