ELECTROCHEMICAL QUARTZ-CRYSTAL MICROBALANCE INVESTIGATION OF SURFACE FOULING DUE TO PHENOL OXIDATION

An electrochemical quartz crystal microbalance is employed for investi gating the formation of inhibitory polyphenol layers on the surface of gold electrodes. The frequency-time profiles are indicative of the fo rmation of a thin insulating polymeric layer that meets the rigid film requirement. and are in good agreement with the voltammetric response . Once access to the monomer is blocked, no further frequency change i s observed. The passivation process is explored as a function of the s pecific phenolic compound. its concentration, and operational conditio ns. Comparison to the charge passed during the film deposition indicat es that the efficiency of the polymerization process is dependent upon the phenol concentration. Valuable insights are also gained for the e ntrapment of glucose oxidase within the electrochemically grown polyph enol. (C) 1998 Elsevier Science S.A. All rights reserved.