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Updated: May 27, 2026
10:28
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Evidence for water structuring forces between surfaces.
Christopher Stanley1, Donald C Rau
1Neutron Scattering Science Division, Oak Ridge National Laboratory, PO Box 2008 MSC 6473, Oak Ridge, TN 37831.
Current Opinion in Colloid & Interface Science
|November 30, 2011
Summary
Structured water between surfaces generates energy. This hydration force explains interactions in biological systems like DNA and cellulose, showing repulsion and attraction due to water
Area of Science:
- Biophysics
- Physical Chemistry
- Surface Science
Background:
- Water molecules exhibit structured behavior on surfaces.
- Interactions between biological structures are influenced by surface-bound water.
- The osmotic stress technique is a key method for measuring forces in biological systems.
Purpose of the Study:
- To review and elucidate the underlying hydration force in biological systems.
- To analyze the forces governing interactions between highly charged DNA and nonpolar hydroxypropyl cellulose.
- To explore conditions leading to repulsion and attraction, and solute exclusion from macromolecular surfaces.
Main Methods:
- Utilizing the osmotic stress technique for force measurements.
- Analyzing interactions on diverse biological structures.
- Comparing force profiles of DNA and hydroxypropyl cellulose.
Main Results:
- Identified commonalities in force measurements across various biological structures, suggesting a universal hydration force.
- Observed conditions for both net repulsion and attraction between surfaces.
- Demonstrated exclusion of chemically different solutes from macromolecular surfaces, consistent with hydration force effects.
Conclusions:
- The observed interaction forces between biological surfaces can be attributed to the perturbation of structured surface water.
- Hydration forces play a significant role in the assembly and interaction of biological macromolecules.
- Understanding hydration forces is crucial for comprehending molecular interactions in biological and material science contexts.
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