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Free Volume in Membranes: Viscosity or Tension?
1Department of Anesthesiology and Pain Management, UT Southwestern, Dallas, TX, USA.
Open Journal of Biophysics
|May 31, 2016
Summary
Fluorescent probe diffusion measures membrane free volume, not viscosity. Changes in probe mobility reflect membrane tension, offering insights into cell membrane domains and cytoskeleton interactions.
Area of Science:
- Biophysics
- Cell Biology
- Materials Science
Background:
- Fluorescent probe diffusion is commonly used to estimate membrane viscosity.
- This technique's interpretation may be limited in complex biological systems.
Purpose of the Study:
- To re-evaluate the interpretation of fluorescent probe diffusion measurements in cell membranes.
- To highlight the relationship between probe mobility, membrane free volume, and membrane tension.
Main Methods:
- Analysis of fluorescent probe diffusion dynamics.
- Theoretical consideration of membrane properties.
Main Results:
- Fluorescent probe diffusion directly assays membrane free volume, not viscosity.
- Probe mobility changes correlate with alterations in membrane tension.
- Membrane tension is a more suitable variable than viscosity for interpreting complex membrane structures.
Conclusions:
- Interpreting probe mobility as a measure of free volume and tension provides a more accurate understanding of cell membranes.
- This perspective is crucial for studying membrane domains and cytoskeleton interactions.
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