ELECTROCHEMICAL STERILIZATION OF BACTERIA USING A GRAPHITE ELECTRODE MODIFIED WITH ADSORBED FERROCENE

Electrochemical sterilization of the marine gram-negative bacterium Vi brio alginolyticus cells was carried out using basal-plane pyrolytic g raphite electrode modified with adsorbed ferrocene. When cyclic voltam metry was taken in V. alginolyticus cell suspension using an electrode modified with ferrocene at a scan rate of 20 mV per s at 25 degrees C , an electrocatalytic oxidation occurred above 0.1 V versus saturated calomel electrode (see). Peak current was observed around 0.3 V vs see . The bacteria which attached to the ferrocene modified electrode were sterilized at 0.2 V vs see in sterile seawater, whereas they were ste rilized at 0.8 V vs see when using a bare graphite electrode. This ste rilization was due to the electrochemical oxidation of the intracellul ar substance and not to the toxicity of ferrocene. V. alginolyticus ce lls in sterile seawater were completely sterilized after 10 min by app lying 0.2 V vs see. (C) 1997 Published by Elsevier Science Ltd.