This award will support a group of researchers at Syracuse University under the direction of Prof. J. Fendler to carry out collaborative research with a similar group at the Instituto National de Investigaciones Nucleares in Mexico City, Mexico, under the direction of Prof L. A. Fucugauchi. Over the past several years the collaborators have been successfully engaged in the preparation and characterization of micelles, microemulsions, liquid crystals, vesicles and polymerized vesicles. All of these molecular aggregates have a common theme in that they mimic the functions of a biological membrane. For the proposed period of collaboration, the researchers intend to pursue the investigation of membrane mimetics using nuclear techniques with the long range goal of increasing our understanding of the chemistry of biological membranes. The collaborators' work has been characterized by its productivity, and mutual benefits. Vesicles and polymerized vesicles have been prepared in the United States while microemulsions and liquid crystals have been prepared and characterized in Mexico. The structures and morphologies of the aggregates have been investigated by the U.S. group using static and dynamic light scattering and intrinsic and extrinsic spectroscopic methods. The Mexican group, on the other hand, has used polarized light microscopy for the characterization of liquid crystals and is experienced in the use of positron annihilation techniques to determine phase changes in the different systems. The use of these techniques has allowed the investigators to detect subtle and significant changes in surfactant morphologies. Additionally, the proposed research has a significant potential for application to enhanced oil recovery, controlled drug release, catalysis, and the control of various chemical processes.