Conductive Biomaterials Based on Chemically-Modified Silk
Chemistry, Western Washington University
April 23, 2015
Foege N130A, Wallace H. Coulter Seminar Room
Biocompatible materials capable of conducting electricity have numerous biomedical applications including use as electrodes for neurological stimulation and recording, tissue engineering, artificial muscles, and stimuli-responsive actuators or sensors. Therefore, we are developing new ‘soft’, flexible, polymer-based electrode materials that can be integrated into biological tissues with minimal damage to the host. To this end, we have synthesized composite materials composed of the polypeptide silk fibroin (for mechanical strength, flexibility, biocompatibility) and poly(pyrrole) or poly(3,4-ethylenedioxythiophene) (conducting polymers for electrical interfacing). Covalent attachment of negatively charged, hydrophilic sulfonic acid groups to the silk protein can selectively promote pyrrole absorption and polymerization within the modified films to form a conductive, interpenetrating network of polypyrrole and silk that is incapable of delamination. Using this strategy, we are able to produce silk-based ‘electrodes’ with various architectures including fibers, 2D films, 3D porous sponges and hydrogels. In addition, we have found that specially designed silk-polypyrrole composites can function as electromechanical bending actuators, which show immense promise for the development of implantable valves or drug delivery devices.
Dr. Murphy is currently an assistant professor in the Department of Chemistry at Western Washington University. She received a Bachelor of Science in Engineering Technology and a Bachelor of Arts in Chemistry at Western Washington University in Bellingham, WA in 2001. She obtained her Ph.D. at the University of California at Berkeley in 2006, working with Jean Fréchet. She then became postdoctoral fellow in the Biomedical Engineering department at Tufts University in Medford, MA, working with David Kaplan. She began her current position at WWU in winter 2010.