A microcontinuum model of electrokinetic coupling in the extracellular matrix: perturbation formulation and solution

A microcontinuum model is formulated to describe electrokinetic transduction interactions and transport in the extracellular matrix (ECM). A unit cell approach is used in which the ECM is modeled as an ordered array of charged solid cylinders surrounded by a diffuse double layer. The model includes the effects of overlapping diffuse double layers and the associated electrokinetic coupling within the bulk of the unit cell as exist under physiological conditions. A system of coupled differential equations is developed to describe the electrokinetic coupling within the unit cell. A perturbation expansion of the governing system is solved using the numerical grid generation technique and the electromechanical coupling coefficients for articular cartilage are determined