Classical colloid science investigates the finely dispersed materials of one phase in a second phase. The electrochemical interaction between these phases is one important aspect.

Almost any particle in contact with a liquid acquires an electrical surface charge, as do macroscopic solids. While electrophoresis is commonly used to investigate the particle/liquid interaction of dispersions, the method of streaming potential gives insight into the interfacial charge and the adsorption properties of solid materials. In both cases, the relative movement between the solid and the liquid phases reveal the zeta potential.

Zeta-potential measurements aid scientists in the fields of chemistry and material science to improve defined surface properties and develop new, specialized material properties e.g. for polymers, textiles, ceramics, glass and shampoos. In the case of coated materials, for example, a zeta-potential measurement can ensure that the coating is applied under optimal conditions. The measurement can also be used to achieve low-energy surfaces which repel pollutants.