Ion mediated crosslink driven mucous swelling kinetics

Abstract

We provide qualitative predictions on the rheology of mucus of healthy individuals (Wild Type or WT-mucus) versus those infected with Cystic Fibrosis (CF-mucus) using an experimentally guided, multi-phase, multi-species ionic gel model. The theory which accounts for mucus (as polymer phase), water (as solvent phase) and ions, H+, Na+ and Ca2+, is linearized to study the hydration of spherically symmetric mucus gels and calibrated against the experimental data of mucus diffusivities. Near equilibrium, the linearized form of the solution reduces to an expression similar to the well known kinetic theory of neutral gels. Numerical studies reveal that the Donnan potential is the dominating mechanism driving the mucus swelling/deswelling transition. However, the altered swelling kinetics of the Cystic Fibrosis infected mucus is not merely governed by the hydroelectric composition of the swelling media, but also due to the altered movement of electrolytes as well as due to the defective properties of the mucin polymer network.