Preparation and characterization of conductive and photoluminescent DNA-templated polyindole nanowires

ACS Nano. 2010 Apr 27;4(4):2149-59. doi: 10.1021/nn9014533.

Abstract

Polyindole (PIn) nanowires were formed on a lambda-DNA template by chemical oxidation of indole using aqueous FeCl3. The resulting nanowires are smooth, regular, conductive and had diameters in the range of 5-30 nm. These features allow them to be aligned by molecular combing and studied by scanned conductance microscopy, conductive AFM, and two-terminal I-V measurements. Using this combination of measurements, we find that the conductivity of PIn/DNA nanowires is between 2.5 and 40 S cm(-1) at room temperature, which is substantially greater than that in previous reports on the bulk polyindole conductivity (typically 10(-2)-10(-1) S cm(-1)). The conductance at zero bias shows an Arrhenius-type of dependence on temperature over the range of 233 to 373 K, and the values observed upon heating and cooling are repeatable within 5%; this behavior is consistent with a hopping mechanism of conductivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • DNA / chemistry*
  • Electric Conductivity
  • Indoles / chemistry*
  • Luminescent Agents / chemistry*
  • Microscopy
  • Nanowires / chemistry*
  • Oxidation-Reduction
  • Polymers / chemistry*
  • Silicon / chemistry
  • Silicon Dioxide / chemistry
  • Spectrum Analysis
  • Surface Properties
  • Temperature

Substances

  • Indoles
  • Luminescent Agents
  • Polymers
  • Silicon Dioxide
  • DNA
  • Silicon