Mathematical simulation of isotachophoresis boundary between protein and weak acid

Mathematical simulation of an isotachophoretic boundary between protein and weak acid was made on the assumption of steady state. In order to deal with a protein molecule, a Gaussian model for charge distribution of protein molecule was constructed, based on the assumption that acidic and basic residues on a protein molecule dissociate independently of each other. The results were roughly in agreement with protein stacking experiments with regard to boundary thickness and concentration of the stacked zone.