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Updated: Nov 1, 2025
05:09
Three-dimensional Quantification of Intestinal Mucus Using Whole-mount Tissue Imaging
Published on: September 12, 2025
181
ENHANCED ELECTRODIFFUSIVE TRANSPORT ACROSS A MUCUS LAYER
Owen L Lewis1, James P Keener2
1Department of Mathematics & Statistics, University of New Mexico.
SIAM Journal on Applied Mathematics
|June 28, 2021
Summary
This study models ion diffusion through mucus, revealing how mucus properties affect transport rates. It proposes a mechanism for enhanced hydrogen ion flux, potentially explaining conflicting experimental findings.
Area of Science:
- Biophysics
- Physiological Transport
Background:
- Diffusive transport of ions through mucus is vital in physiology.
- The impact of mucus properties (charge, ion binding) on ion diffusion rates is debated.
- It's unclear if ion diffusion in mucus differs significantly from aqueous solutions.
Purpose of the Study:
- To mathematically describe ionic species transport (hydrogen and chloride) through mucus.
- To account for hydrogen ion binding affinity and interfacial Donnan potential.
- To quantify steady-state fluxes and their dependence on mucus and solution properties.
Main Methods:
- Utilized the Nernst-Planck equations of electrodiffusion.
- Developed a mathematical model for ion transport across mucus layers.
- Quantified steady-state fluxes under varying conditions.
Main Results:
- Modeled the diffusive transport of hydrogen and chloride ions through mucus.
- Demonstrated the influence of mucus binding affinity and Donnan potential on ion flux.
- Identified a mechanism for enhanced hydrogen ion diffusive flux across mucus.
Conclusions:
- The mathematical model provides insights into ion transport dynamics in mucus.
- Mucus properties significantly influence ionic diffusion rates.
- A proposed mechanism may reconcile contradictory experimental data on hydrogen ion transport.
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