Dynamic streaming potential measurements reveal the adsorption of water-borne solutes on solid material surfaces

The property of surface and interfacial charge in colloidal systems, such as solutions of macromolecules, nanoparticle dispersions and emulsions, and their related behavior are commonly characterized irrespective of their final application on solid material surfaces. On the other hand, it is assumed or even known that surface boundaries may alter the behavior of dispersed matter. The combination of conventional zeta potential analyses by the measurements of the electrophoretic mobility (in liquid phase) and the streaming potential (at the solid-water interface) with the dynamic streaming potential method gives a direct access to the interaction of solutes and dispersed particles and emulsion droplets with real material surfaces. The information provided by such a combination of analytical techniques is highlighted by a series of case studies in the fields of hair care, textile care, biomaterials and medical devices. The complementary results help to quantify the affinity of solutes towards material surfaces, adsorption rates, surface coverage, and the dominating mechanism of interaction.