Aerogel and Nanoporoous Materials for Biomolecular Applications Chenyue Xing and Roland Faller Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616. E-mail: cxing@ucdavis.edu, rfaller@ucdavis.edu ABSTRACT: The study of lipid structure and phase behavior at the nano-scale is of utmost importance due to implications in understanding the role of the lipids in biochemical membrane processes. Supported lipid bilayers play a key role in understanding real biological systems but they are vastly underrepresented in computational studies. The Vattulainen research group at Tampere University of Technology in Finland has been studying lipids computational in a wide collection and has gained great experience in simulating lipid systems The collaboration between our group and theirs combine the current knowledge of simulating a solid support and different kinds of lipids that we did not previously master. The collaboration also extended to the calculation of pressure profiles of supported lipid bilayers. Preliminary results are encouraging. INTRODUCTION Under the current NSF award (grant No. 0506602), our group (the soft condensed matter simulation group at the University of California, Davis) has been performing computer simulations on supported lipid bilayers in order to understand the behavior of lipid molecules under the influence of a solid support, hydrophobic or hydrophilic with the final goal to describe bilayer aerogel and bilayer xerogel interactions. We first started with a coarse grained simulation model in describing the supported bilayer system so that on a qualitative level, we could understand changes in the lipid bilayers when deposited on a smooth hydrophilic solid surface. We have reported our data in the ACS meeting at Boston in Aug 2007 that the solid support significantly changed the structure of the lipid bilayer and a publication has been submitted [1]. The dynamics of the lipids were also impacted. We have seen that the originallly symmetric structure and dynamics of the two leaflets in a bilayer became heterogeneous after putting a solid support into the system. Lipids close to the support were restrained according to the surface topology of the support. This agrees with the experimental side in this project under the same NSF award. Particularly, the change in lateral pressure from free standing bilayers to supported ones attracted our great interest. That implies the possible existence of surface tension and a