Scanning Force Microscopy Characterization of Biopolymer Films: Gelatin on Mica

  • Greg Haugstad
  • Wayne L. Gladfelter
  • Elizabeth B. Weberg
  • Rolf T. Weberg
  • Timothy D. Weatherill

Abstract

Scanning force microscopy of thin gelatin films on mica reveals two distinct film components with characteristic frictional, morphological and stability signatures. A high-friction continuous film 1–4 nm thick strongly adheres to mica, while a low-friction component is adsorbed as porous islands on top of or small domains within, the high-friction layer and is more easily perturbed by the scanning process. A high-force scanning procedure remarkably transforms the molecularly rough high-friction film into the molecularly smooth low-friction component if a sufficient amount of water is present in or on the film. The nanostructure of both the high- and low-friction components is imaged using a nanometer-scale asperity of gelatin attached to the SFM tip. The anticipated network structure of gelatin is observed on the high-friction layer. The low-friction material is interpreted as moieties of intramolecularly folded gelatin, with thickness (1.5±0.2 nm) equal to the diameter of the collagen-fold triple helix, containing substantial structural water.

Keywords

Frictional Force Gelatin Film Scan Force Microscopy Gelatin Molecule Friction Force Microscopy 
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 1997

Authors and Affiliations

  • Greg Haugstad
    • 1
  • Wayne L. Gladfelter
    • 1
  • Elizabeth B. Weberg
    • 2
  • Rolf T. Weberg
    • 2
  • Timothy D. Weatherill
    • 2
  1. 1.Center for Interfacial EngineeringUniversity of MinnesotaMinneapolisUSA
  2. 2.E.I. du Pont de Nemours and Co.BrevardUSA

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