title: Gold-gold junction electrodes:the disconnection method.
abstract: The formation of gold-gold junction electrodes for application in electroanalysis is described here based on electro-deposition from a non-cyanide gold plating bath. Converging growth of two hemispherical gold deposits on two adjacent platinum microelectrodes (both 100 µm diameter in glass, ca. 45 µm gap) followed by careful etching in aqueous chloride solution was employed. During growth both gold hemispheres "connect" and during etching "disconnection" is evident in a drop in current. Gold-gold junctions with sub-micron gaps are formed and applied for the electroanalytical detection of sub-micromolar concentrations of hydroquinone in 0.1 M phosphate buffer pH 7 (E(rev) = 0.04 V vs. SCE) and sub-micromolar concentration of dopamine in 0.1 M phosphate buffer pH 7 (E(rev) = 0.14 V vs. SCE). The potential future uses in analysis and limitations of gold-gold junction electrodes are discussed.
authors: Department of Chemistry, University of Bath, Bath BA2 7AY, UK.
authors: Sara E C
authors: SE
authors: Dale
authors: Anne
authors: A
authors: Vuorema
authors: Ellen M Y
authors: EM
authors: Ashmore
authors: Barbara
authors: B
authors: Kasprzyk-Horden
authors: Mika
authors: M
authors: Sillanpää
authors: Guy
authors: G
authors: Denuault
authors: Frank
authors: F
authors: Marken
mesh_terms: D002712:Chlorides / Q000737:chemistry; D004298:Dopamine / Q000032:analysis; D055664:Electrochemical Techniques; D004566:Electrodes; D006046:Gold / Q000737:chemistry*; D006873:Hydroquinones / Q000032:analysis; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry; D012996:Solutions / Q000737:chemistry
chemical_list: D002712:Chlorides; D006873:Hydroquinones; D012996:Solutions; D010984:Platinum; D006046:Gold; D004298:Dopamine; C031927:hydroquinone