FABRICATION OF CONDUCTING COMPOSITE MATERIALS OF POLYPYRROLE-POLYCAPROLACTONE FUMARATE FOR NERVE REGENERATION

,5 , conduct electricity 6 , and are porous 7 . Polycaprolactone fumarate (PCLF) shown in Figure 1 is a material currently being investigated for use in nerve guidance tubes. PCLF is a cross-linkable biodegradable polymer 8, 9 . The mechanical properties of PCLF can be tuned to make it flexible with a satisfactory tensile strength for suturing, which makes it an ideal material for nerve guidance tubes. Recently this PCLF material has been extended to include a polypyrrole-polycaprolactone fumarate (PPyPCLF) polymer composite that conducts electricity. Because of the well known fact that electrical stimulation aids in the regeneration of multiple types of tissue, polypyrrole has recently gained significant attention as a potential biomaterial for tissue engineering applications 10 . Polypyrrole has gained more interest than other conducting polymers as a biomaterial because of it high conductivity, stability, and biocompatibility 11-13 . Polypyrrole has also been shown to increase neurite extension, which is a critical step in nerve regeneration 3, 5, 6 . However, polypyrrole has poor mechanical properties that make it brittle and difficult to work with. There fore it is necessary to take other approaches to using it, one of which is to formulate blends 14 of polypyrrole with other polymers that have desirable mechanical properties for the intended application. In the present study, incorporation of polypyrrole into PCLF has been investigated. We describe the synthesis, fabrication, and characterization of this novel biomaterial that is an interpenetrating network of polypyrrole in a PCLF scaffold, which is suturable, flexible, biodegradable, and conducting for nerve regeneration applications. Figure 1. Chemical structure of PCLF (top) and PPy (bottom)