Scanning Tunneling Microscopy Studies on Xanthan Gum

  • M. J. Wilkins
  • M. C. Davies
  • D. E. Jackson
  • C. J. Roberts
  • S. J. B. Tendler
  • P. M. Williams

Abstract

The application of the scanning tunneling microscope (STM) to imaging biological molecules has generated much interest over recent years. Research has mainly concentrated on obtaining images of DNA, proteins and small organic molecules. However, the work we present concerns polysaccharides, specifically xanthan gum, commonly used in the food and oil industries. We have employed high-resolution metallic shadowing to overcome some of the problems associated with imaging biological molecules by STM, such as tip-sample interaction effects and lack of conduction. The images displayed demonstrate the ability of the STM to image replicas of discrete polysaccharide molecules. We directly correlate and compare these results with electron micrographs of similarly prepared molecules. In addition, the effect of different sample deposition techniques and substrates on the resultant images of xanthan gum is demonstrated. We discuss the implications for sample preparation procedures for future STM studies on biological molecules.

Keywords

Scan Tunneling Microscope Scan Tunneling Microscope Image Highly Orient Pyrolytic Graphite Spray Deposition Mica Substrate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • M. J. Wilkins
    • 1
  • M. C. Davies
    • 1
  • D. E. Jackson
    • 1
  • C. J. Roberts
    • 1
  • S. J. B. Tendler
    • 1
  • P. M. Williams
    • 1
  1. 1.The VG SPM Laboratory for Biological Applications Department of Pharmaceutical SciencesUniversity of Nottingham University ParkNottinghamUK

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