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Updated: Jun 19, 2026
19:56
Introduction to Solid Supported Membrane Based Electrophysiology
Published on: May 11, 2013
CONTRIBUTION TO THE THEORY OF PERMEABILITY OF MEMBRANES FOR ELECTROLYTES.
1Biochemical Laboratory of the Aichi Medical University, Nagoya, Japan.
The Journal of General Physiology
|October 30, 2009
Summary
Experiments show that membranes like apple skin and collodion are less permeable to anions than cations. This reduced anion mobility significantly impacts membrane potentials and electrolyte diffusion, magnifying cation mobility differences.
Area of Science:
- Physical Chemistry
- Materials Science
- Electrochemistry
Background:
- Membrane permeability is crucial for understanding ion transport.
- Previous studies suggested varying ion selectivity in biological and artificial membranes.
Purpose of the Study:
- To investigate the differential permeability of various membranes to anions and cations.
- To develop a theoretical framework explaining the influence of anion impermeability on membrane electromotive effects and electrolyte diffusion.
Main Methods:
- Experimental studies using apple skin, parchment paper, and dry collodion membranes.
- Theoretical modeling of ion transport and electromotive forces across membranes with varying anion permeability.
Main Results:
- Apple skin and dry collodion membranes exhibit negligible anion permeability.
- Parchment paper shows reduced, but not zero, anion mobility.
- Theoretical predictions align with experimental observations regarding ion transport and magnified cation mobility differences.
Conclusions:
- Membrane charge and capillary effects significantly impede anion mobility.
- Anion impermeability dramatically alters cation mobility, magnifying differences observed in free solutions.
- The findings provide insights into ion selectivity mechanisms in membranes.
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