Equilibrium and kinetic studies of a chemical model of active transport: Membrane transport of potassium salts by cryptand carriers driven by potassium ion complexation

Abstract

A theoretical framework of energy transduction in membranes was used as a point of departure for the design of a simple chemical model of primary active transport (reaction pumping). In the model, cryptand carriers transport potassium salts across a bulk liquid membrane, driven by the complexation of potassium by a dicarboxylate crown ether in one aqueous phase. Both the equilibrium position and kinetic behavior of the model system could be predicted from the theoretical framework. Experimental verification of the predictions confirms the fitness of the theoretical framework and provides a design tool for the formulation of new membrane transport systems.