Application of atomic force microscopy in the study of microbiologically influenced corrosion

This paper demonstrates the use of the atomic force microscope in high-resolution topographical imaging of bacteria, biofilm, and corroded steel surfaces, and in the quantification of localized corrosion. The nanometric physicochemical and mechanical properties of a single cell and bacterial biofilm surface are characterized by force mapping. The corrosion results in two different sulfate-reducing bacteria cultures showed that the patterns of pitting and the degree of corrosion of mild steel were related to the bacterial isolates. Results from measurement of the tip-biofilm and the tip-cell adhesion forces indicated that the extracellular polymeric substances were mainly distributed in the cell-substratum periphery or the cell-cell interface in the biofilm.