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Updated: Jun 10, 2026
10:33
A Method for Determination and Simulation of Permeability and Diffusion in a 3D Tissue Model in a Membrane Insert System for Multi-well Plates
Published on: February 23, 2018
[Relation between effective and real solute permeability coefficients through polymeric membrane]
Jolanta Jasik-Slezak1, Andrzej Slezak
1Katedra Zdrowia Publicznego, Politechnika Czestochowska. ajslezak@zim.pcz.pl
Polimery W Medycynie
|July 24, 2010
Summary
This study models solute permeability through membranes, revealing a nonlinear relationship between membrane transport and solution concentration. Increased concentration can lead to diffusion-convection mass transport.
Area of Science:
- Thermodynamics
- Membrane Science
- Physical Chemistry
Context:
- Understanding solute transport across membranes is crucial in various scientific fields.
- The Kedem-Katchalsky formalism provides a thermodynamic framework for analyzing membrane transport.
- Previous models often simplified the complex interplay between solute concentration and membrane permeability.
Purpose:
- To develop a mathematical model for the relationship between effective and real solute permeability coefficients.
- To investigate the influence of solution concentration on membrane transport parameters.
- To identify conditions leading to diffusion-convection mass transport.
Summary:
- A mathematical model based on Kedem-Katchalsky thermodynamics was developed to describe solute permeability through membranes.
- The model introduces a parameter (zeta s) that quantifies the relationship between effective and real solute permeability coefficients.
- Calculations show that for polymeric membranes, zeta s is a nonlinear function of solution concentration, indicating a shift from stable diffusion.
- The study highlights that breaking symmetry in concentration boundary layers due to gravity can induce instability and diffusion-convection mass transport.
Impact:
- Provides a more nuanced understanding of solute transport in polymeric membranes.
- Offers a quantitative parameter (zeta s) to assess the proximity to a stable diffusion state.
- Identifies critical conditions for the onset of diffusion-convection, relevant for membrane process design and optimization.
- Contributes to the fundamental knowledge of mass transport phenomena in complex systems.
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