Journal of Electroanalytical Chemistry, Vol.610, No.2, 218-226, 2007
Self-assembled monolayers of a hydroquinone-terminated alkanethiol onto gold surface. Interfacial electrochemistry and Michael-addition reaction with glutathione
An electroactive self-assembled monolayer (SAM) was fabricated by covalent attachment of a novel hydroquinone-terminated dodecanethiol onto the gold surface and its electrochemical behavior was investigated using cyclic voltammetry and electrochemical impedance spectroscopy. The capability of the designed SAM in immobilization of organic molecules onto the gold surface was studied utilizing the Michael-addition as a model reaction. The results obtained from cyclic voltammetry, electrochemical impedance and grazing incidence Fourier transform infrared (GI-FTIR) spectroscopy revealed that, upon applying an anodic potential to the Au-SAM electrode system in the presence of glutathione, the electrochemically generated p-quinone participated in a Michael-addition reaction with glutathione and the corresponding Michael adduct was formed at the solid-liquid interface. The kinetic parameters were then derived for this interfacial Michael-addition reaction. (c) 2007 Elsevier B.V. All rights reserved.
Keywords:self-assembled monolayers;cyclic voltammetry;impedance spectroscopy;nanolayers;Michael-addition