This Small Business Innovative Research (SBIR) Phase I project proposes to develop the non-invasive technique of Surface Light Scattering Spectroscopy (SLSS) to characterize biomembranes and enhance the understanding of fluid interfaces. SLSS promises a distinct advantage over current methods for pharmacokinetics screening of drug candidates: the ability to quickly and accurately measure key biophysical characteristics and behavior of complex interfaces without physical disturbance. Successful development of this approach will contribute to reducing the high cost of Absorption, Distribution, Metabolism,<br/>and Excretion (ADME) drug screening. <br/><br/>An interdisciplinary team has been formed to assess the feasibility of employing SLSS for lipid characterization and to examine technical issues and refinements needed for robust and accurate determination of biomembrane properties. Phase I uses a laboratory instrument to obtain measurements that can be verified against published literature, including compounds that are of interest to blood-brain barrier studies. Phase II includes refinement of an advanced instrument design and fabrication and testing of a commercial prototype.