Dielectric Behaviour of Octyl-beta-D-Glucopyranoside Micelles in water and in water-glycine solutions.

The dielec. permittivity, viscosity, and d. of octyl - beta-D-glucopyranoside (OBG) and glycine (G) aq. solns. (with different OBG/G mol. ratios) were measured as a function of surfactant concn. and temp. to study the effect of the amino acid on the surface of the glucoside micelles. The amino acid shows an appreciable influence on the thermodn. stability of the surfactant aggregates. However viscometric, volumetric, and dielec. results indicate that glycine is not involved in the micellar surface. Such a result indicates that the stabilization of the OBG micellar assemblies (obsd. previously) is due mainly to a decrease of the soly. of the hydrocarbon tail and/or to an increase of the interfacial tension between the micellar oil core and the solvent rather than to short-range interactions between glycine and OBG polar head groups.