Electrodiffusion active pump model with asymmetric immersed chemical potentials

Active pumps are crucial for cellular homeostasis, keeping physiological states. The new computational model for active pump resolves sharply thin space charge layers around membranes in a non-asymptotic manner without the assumption of homogeneous local and global electroneutrality in electrodiffusion. The microscopic representation of kinetic interaction between the water semi-permeable membrane and solutes mediated by the prescribed continuous chemical potential barriers through fluctuation-dissipation satisfies the macroscopic osmotic balance, i.e. van't Hoff law, when there are no active pumps. The biophysical model shows the expected homeostatic volume regulation with active pumps and swelling phenomena without their working. The model framework is applicable to rigorously characterize physiological and disease states involving the coupled electrical and osmotic effects with possible membrane movement.