Biofilm formation and local electrostatic force characteristics of Escherichia coli O157:H7 observed by electrostatic force microscopy

Abstract

The authors report growth media dependence of electrostatic force characteristics in Escherichia coli O157:H7 biofilm through local measurement by electrostatic force microscopy (EFM). The difference values of electrostatic interaction between the bacterial surface and the abiotic surface show an exponential decay behavior during biofilm development. In the EFM data, the biofilm in the low nutrient media shows a faster decay than the biofilm in the rich media. The surface potential in the bacterial cells was changed from 957 to 149 mV. Local characterization of extracellular materials extracted from the bacteria reveals the progress of the biofilm formation and functional complexities. © 2007 American Institute of Physics.