An electrochemical investigation of the fouling of a model surface by a coliform bacterium

Abstract
An electrochemical investigation of the fouling of metal surfaces by Enterobacter aerogenes was made using the technique of cyclic voltammetry with platinum electrodes. The platinum electrodes were incubated in a tryptic soy broth inoculated with the test organism under conditions of culture age, cell concentration, temperature and time which were predetermined to optimize attachment. Light microscopy and image analysis software was used to verify attachment of the bacteria to the electrode surface. Cyclic voltammetric measurements were made on the electrodes transferred to the electrochemical cell containing phosphate buffer, pH 7.0, at 25°C. The surface charge density resulting from oxidation of the bacterial cell attachments was determined from the difference in the anodic oxidation and reduction areas by computer integration. A decreasing trend in surface charge density of the electrodes during 30 min of potential cycling was partially attributed to the removal of 11 to 38% of the bacterial cells, while plate counts indicated the release of 6 to 22% live cells from the surface.