Bile salts are the natural amphiphilic detergents that participate in numerous processes such as intestinal hydrolysis, dispersion, and digestion of lipids, cholesterol solubilization, and drug absorption. Investigation of the interaction of bile salts with a reverse microemulsion based on Aerosol OT (AOT) opens up opportunities for understanding their functioning at the interface, near the cell membrane, with using of the simple model system. The conductivity of water/AOT/decane microemulsions at the temperature induced percolation conditions are obtained in the presence of some bile salts, which differs by the number and position of the hydroxyl groups for sterane backbone of the molecule. The quantitative parameters used to describe electric percolation are compared, as well as the activation energy of the transition. It was found that the incorporation of molecules of the investigated bile salts into the interface of AOT micelles favors more or less to the percolation transition in the system. NMR spectroscopy showed that the addition of bile salts into the microemulsion influences the self-diffusion coefficients of the components and the dimensions of the micelles.
bile salts, electric percolation, surfactant layer, diffusion in micelle
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