An inexpensive, non destructive and rapid quality control (QC) procedure for nano-pore silicon membranes is presented. Membranes with different pore sizes were characterized in terms of glucose diffusion and by electrical resistance measurements. Electrical resistance results versus membrane pore size allowed to trace a reference curve to be used to verify the machining process. Diffusion was plotted versus conductance data. An experimental linear relationship was determined, which allows to predict the membrane diffusion properties without running destructive diffusion tests. (C) 2004 Elsevier B.V. All rights reserved.