The Electric Double Layer and The Donnan Equilibrium in Relation to Plant Cell Walls

Abstract

Space in plant tissues into "water free space" (W.F.S.) and "Donnan free space" (D.F.S.) is examined in systems which contain electrically charged surfaces separated by various distances. It is suggested that plant cell walls should be described in terms of a system of electric double layers and not by classical Donnan equations. An approximate theory is presented which resl1lts in an expression for the equivalent width of D.F.S. in terms of the external concentration but which is independent of the surface charge density.