Self-assembly of DNA-templated polypyrrole nanowires: Spontaneous formation of conductive nanoropes

Abstract

Polypyrrole nanowires formed by polymerization of pyrrole on a DNA template self-assemble into rope-like structures. These 'nanoropes' may be quite smooth (diameters 5-30 nm) or may show frayed ends where individual strands are visible. A combination of electric force microscopy, conductive atomic force microscopy and two-terminal current-voltage measurements show that they are conductive. Nanoropes adhere more weakly to hydrophobic surfaces prepared by silanization of SiO2 than to the clean oxide; this effect can be used to aid the combing of the nanoropes across microelectrode devices for electrical characterization. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA.