Role of Channel Wall Conductance in the Determination of ζ-Potential from Electrokinetic Measurements

Abstract

The classical Smoluchowski formula for streaming potential is shown to be not applicable to the channels (pores) with conducting walls. The classical procedure of accounting for surface conductivity may also be ineffective in some cases. Measurements of streaming current instead of streaming potential are clearly beneficial in this case. Variation of channel height may also be used to extrapolate to true values of ζ-potential not complicated by the wall conductivity.