Self Assembled Polymer Scaffolds for Liver Mimics

1. Self Assembled Polymer Scaffolds for Liver Mimics Padmavathy Rajagopalan, Virginia Polytechnic Institute and State University, DMR 0907590 Self-assembled polyelectrolyte multilayers (PEMs) have gained tremendous popularity over the past decade and have been incorporated in diverse applications. However, the fabrication of detachable and free-standing PEMs has proven to be difficult. We report the design of detachable, free-standing, and biocompatible PEMs comprised of hyaluronic acid (anionic PE) and chitosan (cationic PE). These PEMs can be detached from an underlying inert substrate without any post-processing steps. We are currently designing biomaterial scaffolds that can be used in liver tissue engineering. Detachable PEMs will be assembled using galactose-conjugated chitosan. Galactose ligands are incorporated on the backbone of the chitosan polymer through reactions with lactobionic acid. The degree of substitution was calculated using 1H NMR. Current studies are focused upon monitoring hepatocyte phenotype as a function of galactose concentration. Detachable, free-standing PEM Schematic for the synthesis of galactose-chitosan

2. Self Assembled Polymer Scaffolds for Liver Mimics Padmavathy Rajagopalan, Virginia Polytechnic Institute and State University, DMR 0907590 In July 2009, PI Rajagopalan conducted a workshop on Biomaterials and Tissue Engineering at the Catholic University (Washington DC) to a group of minority high school students organized by the Institute for High Performance Learning, and the Center for Quality Urban Education. The goals of the camp were to provide informal, supplementary, STEM education programs in an extended learning community.  In July 2009, PI Rajagopalan also conducted a presentation on Biomaterials and Tissue Engineering to students enrolled in the NASA INSPIRE (Interdisciplinary National Science Project Incorporating Research and Education Experience) Collegiate Summer Experience and to female high-school students enrolled in Virginia Tech’s CTech2 program (sponsored by the Center for the Enhancement of Engineering Diversity).  In 2009, graduate student, Adam Larkin presented posters at the annual AIChE and BMES conferences. Larkin A, Davis RM and Rajagopalan P. Viscoelastic Properties of Biocompatible Polyelectrolyte Multilayers. Biomedical Engineering Society Meeting, October 2009 and AIChE Annual Meeting, November 2009. Reisha Parham, undergraduate student in the Department of Chemical Engineering (PI Rajagopalan’s research group) presented a poster entitled “Measurement of the Mechanical Properties of Polymeric Scaffolds Used in 3-D Liver Mimics” at the Virginia Tech Multicultural Academic Opportunities Program Symposium