Sterilization by a Pulsed Electric Field with Dendritic Gold Electrodes

Abstract

The dendritic gold electrodes effectively inactivated Escherichia coli (E. coli) by pulsed electric field (PEF) sterilization. Two phenomena are involved: (1) The dendritic structures induce a dielectrophoretic (DEP) force which drives E. coli toward the vicinity of the dendrites. (2) High-intensity electric fields around the dendrite tips distort the cell walls of E. coli as a result of potential disturbance, which subsequently kill the E. coli. The inactivation rate of E. coli on the dendritic electrodes depended on the pulse frequency more strongly than on an as-sputtered smooth electrode, suggesting that the DEP force is operative during PEF sterilization.