Síntese de nanofibras de polipirrol para potencial aplicação em conduto biodegradável para regeneração nervosa

Abstract

Injury of peripheral nerves of accidents at work or home are common carriers and scallfolds of biodegradable polymers with temporary structural function to assist in the regeneration of damaged living tissue are being explored. Conducting polymers such as polypyrrole (PPy), have also been explored because of biocompatibility to various cell types and ease of synthesis. Artificial Nerve Guidance Conduits with multifunctional growth factors (GF) have been studied to improve the regeneration of injured peripheral nerves. The main objective is to prepare polymer composites of poly (lactic - co - glycolic acid) - (PLGA) with PPy nanofibers able to act as a conduit in peripheral nerve regeneration. PPy nanofibers were synthesized via chemical oxidative polymerization with different dopants. Films PLGA / nanofiber PPy / tacrolimus (FK506) were prepared by sandwich solvent casting method. The PPy nanofibers were characterized by FTIR, SEM, electrical impedance spectroscopy and TGA. In vitro degradation of PLGA/PPy composite films was also evaluated. PPy nanofibers of electrically condutive 8.10-4 S / cm were obtained with dopant p-toluenesulfonic acid (PTSA) in the ratio [dop]: [Py] = 4 and 0 ° C. Films PLGA / PPy-nanofibers exhibit irregular surface morphology with voids that can serve as framewoks for cell growth guided. The degradation of PLGA / PPy films did not alter the pH of the buffer solution, an increase of thickness and mass loss was in the range of 7-21% until 28 days of degradation reviews. The addition of nanofibers favored the process of mass loss of about 4% for the PLGA / PPy thicker (≥ 0.6g of PLGA) films and 6% for thinner films (0.2 g PLGA) until 28 days degradation.