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THE THICKNESS OF THE WALL OF THE RED BLOOD CORPUSCLE.
1Physiological Laboratory, Princeton University, Princeton, N. J.
The Journal of General Physiology
|October 30, 2009
Summary
Fricke's assumption on erythrocyte dielectric constant is validated for thin layers but may underestimate values for thicker liquid membranes. This study calculates dielectric constants for polar groups in unimolecular films.
Area of Science:
- Biophysics
- Cell Biology
- Physical Chemistry
Background:
- The dielectric constant of cell membranes is crucial for understanding electrical properties.
- Fricke's assumption of a dielectric constant of 3 for erythrocyte walls is widely used but requires further investigation.
Purpose of the Study:
- To evaluate the validity of Fricke's assumption regarding the erythrocyte wall's dielectric constant.
- To determine the dielectric constants of polar groups in unimolecular films.
Main Methods:
- Theoretical analysis of dielectric properties based on layer thickness.
- Experimental determination of dielectric constants for unimolecular films.
Main Results:
- Fricke's assumption (dielectric constant = 3) is accurate for solid layers and thin liquid layers (up to bimolecular thickness).
- For thicker liquid erythrocyte layers, the dielectric constant can significantly exceed 3.
- Calculated dielectric constants for polar groups in unimolecular films are provided.
Conclusions:
- The dielectric constant of the erythrocyte wall is dependent on its physical state and thickness.
- Fricke's assumption is a simplification that holds under specific conditions.
- Accurate dielectric constants for membrane components are essential for biophysical models.
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