title: Preparation and characterization of conductive and photoluminescent DNA-templated polyindole nanowires.
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.
authors.affiliation: Chemical Nanoscience Laboratories, School of Chemistry, Bedson Building, Engineering and Advanced Materials, Newcastle University, Newcastle Upon Tyne NE1 7RU, United Kingdom.
authors.forename: Reda
authors.initials: R
authors.lastname: Hassanien
authors.forename: Mariam
authors.initials: M
authors.lastname: Al-Hinai
authors.forename: Said A
authors.initials: SA
authors.lastname: Farha Al-Said
authors.forename: Ross
authors.initials: R
authors.lastname: Little
authors.forename: Lidija
authors.initials: L
authors.lastname: Siller
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Wright
authors.forename: Andrew
authors.initials: A
authors.lastname: Houlton
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Horrocks
mesh_terms: D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D004553:Electric Conductivity; D007211:Indoles / Q000737:chemistry*; D049408:Luminescent Agents / Q000737:chemistry*; D008853:Microscopy; D053770:Nanowires / Q000737:chemistry*; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013057:Spectrum Analysis; D013499:Surface Properties; D013696:Temperature
chemical_list: D007211:Indoles; D049408:Luminescent Agents; D011108:Polymers; D012822:Silicon Dioxide; D004247:DNA; D012825:Silicon