Facile template preparation of novel electroactive scaffold composed of polypyrrole-coated poly(glycerol-sebacate-urethane) for tissue engineering applications

Abstract

• Porous poly(glycerol sebacate urethane)-based scaffolds prepared. • Loading of ZnO nanoparticles and in-situ polymerization of pyrrole in the scaffolds performed. • Electrical conductivity (4 ∼ 7 × 10 -2 S/cm) was obtained for pyrrole containing scaffolds. • ZnO particles could effectively suppress bacterial growth. • The scaffolds were elastic with full shape-retention ability under cyclic loading. Poly(glycerol-sebacate-urethane) (PGS-U) is an attractive candidate as a super-elastic and biocompatible scaffold for inserting nanoparticles and polymers with a straightforward synthesis. Herein, a series of PGS-U scaffolds with various crosslink densities was prepared for subsequent polypyrrole (PPy) polymerization. The in-situ polymerization of PPy was employed to deposit the PPy particles throughout the scaffolds, and the continuous electrically conductive pathways were built within the scaffolds. Moreover, due to their favorable mechanical and anti-bacterial properties, zinc oxide (ZnO) nanoparticles were embedded within the scaffold. The composition of the scaffolds was confirmed by different characterization techniques, including FTIR, FE-SEM, and EDX. Static and cyclic compression tests were conducted to evaluate the mechanical performance of scaffolds under dry and hydrated conditions. All scaffolds presented high structural stability and full shape recovery after releasing the load. They were thermally stable up to at least 200 °C. The addition of PPy boosted the electrical conductivity, and the inclusion of ZnO particles improved the surface hydrophilicity and anti-bacterial behavior of the scaffolds. Altogether, this study suggests the further developments of these nanocomposites as satisfactory electrically conductive scaffolds for tissue engineering applications.