title: Single particle detection by area amplification: single wall carbon nanotube attachment to a nanoelectrode.
abstract: We describe the electrochemical detection of single nanoparticle (NP) attachment on a nanoelectrode by the increase in the active electrode area. The attachment of gold NP-decorated single wall carbon nanotubes (Au-SWCNTs) was observed by their current-time transients for ferrocenemethanol (FcMeOH) oxidation. Since the attached Au-SWCNT increases the electroactive area available for FcMeOH oxidation, the current increases after attachment of the particle. The "staircase" shape of the current response establishes that the particles do not become deactivated for the outer-sphere electron transfer reaction after attachment. Au-SWCNTs migrate to and are held at the nanoelectrode by an electric field. However, SWCNTs that are not decorated with a gold NP produce only a sharp transient ("blip") response.
authors.affiliation: Center for Electrochemistry, Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Jun Hui
authors.initials: JH
authors.lastname: Park
authors.forename: Scott N
authors.initials: SN
authors.lastname: Thorgaard
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Bard
mesh_terms: D055664:Electrochemical Techniques; D004566:Electrodes; D005296:Ferrous Compounds / Q000737:chemistry; D036103:Nanotechnology / Q000295:instrumentation*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D010316:Particle Size; D013499:Surface Properties
chemical_list: D005296:Ferrous Compounds; D037742:Nanotubes, Carbon; C071550:ferrocenemethanol