MC-40 membrane samples modified with a thin MF-4SC layer containing inorganic oxide particles have been synthesized. Deposition of an MF-4SC layer raises the diffusion permeability of the membrane. Insertion of ZrO2or SiO2nanoparticles into this layer enhances the ion transport selectivity in terms of the cation transport number. The best results are obtained with oxide particles synthesized in the pores of the deposited layer. © 2010 Pleiades Publishing, Ltd.