Analytical and Bioanalytical Chemistry

, Volume 391, Issue 5, pp 1899–1905

Towards chemical analysis of nanostructures in biofilms I: imaging of biological nanostructures

Authors

  • Thomas Schmid
    • Department of Chemistry and Applied BiosciencesETH Zurich
  • Johannes Burkhard
    • Department of Chemistry and Applied BiosciencesETH Zurich
  • Boon-Siang Yeo
    • Department of Chemistry and Applied BiosciencesETH Zurich
  • Weihua Zhang
    • Department of Chemistry and Applied BiosciencesETH Zurich
    • Department of Chemistry and Applied BiosciencesETH Zurich
Original Paper

DOI: 10.1007/s00216-008-2100-2

Cite this article as:
Schmid, T., Burkhard, J., Yeo, B. et al. Anal Bioanal Chem (2008) 391: 1899. doi:10.1007/s00216-008-2100-2

Abstract

Due to their direct influence on the stability of bacterial biofilms, a better insight into the nanoscopic spatial arrangement of the different extracellular polymeric substances (EPS), e.g., polysaccharides and proteins, is important for the improvement of biocides and for process optimization in wastewater treatment and biofiltration. Here, the first application of a combination of confocal laser-scanning microscopy (CLSM) and atomic force microscopy (AFM) to the investigation of river-water biofilms and related biopolymers is presented. AFM images collected at selected areas of CLS micrographs dramatically demonstrate the heterogeneity of biofilms at the nanometer scale and the need for a chemical imaging method with nanoscale resolution. The nanostructures (e.g., pili, flagella, hydrocolloids, and EPS) found in the extracellular matrix are classified according to shape and size, which is typically 50–150 nm in width and 1–10 nm in thickness, and sets the demands regarding spatial resolution of a potential chemical imaging method. Additionally, thin layers of the polysaccharide alginate were investigated. We demonstrate that calcium alginate is a good model for the EPS architecture at the nanometer scale, because of its similar network-like structure.

https://static-content.springer.com/image/art%3A10.1007%2Fs00216-008-2100-2/MediaObjects/216_2008_2100_Figa_HTML.gif
Figure

CLSM-AFM allows imaging of nanometer-sized extracellular structures

Keywords

BiofilmExtracellular polymeric substances (EPS)AlginateConfocal laser-scanning microscopy (CLSM)Atomic force microscopy (AFM)

Copyright information

© Springer-Verlag 2008