Imaging in Liquid and the Determination of Surface Electrical Properties

Imaging in Liquid and the Determination of Surface Electrical Properties 

Although most membrane technologists now recognize the important contribution of membrane surface electrical properties in defining the separation characteristics, there remains confusion as to how best to describe and quantify such interactions. There is an unfortunate tendency in the applied membrane 

Moreover, if the surface potential or surface charge of the colloid has been determined and the solution is of defined ionic content, it is possible to calculate the potential or charge of the surface under investigation by matching the experimentally obtained curves to theoretical calculations based on electrical double layer theory. In the example shown, the best-fit membrane surface charge was —0.00114 Cm and the best-fit membrane surface potential was —64 mV. Furthermore, an important advantage of the colloid probe technique is that it allows exploration of variations in surface electrical interactions at different points on the membrane surface, as the following section shows. 

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