Effective nerve cell modulation by electrical stimulation of carbon nanotube embedded conductive polymeric scaffolds

Abstract

Biomimetic biomaterials require good biocompatibility and bioactivity to serve as appropriate scaffolds for tissue engineering applications. Recent developments demonstrated that the unique properties of carbon nanotubes (CNTs) can enhance neural cell growth and axon organization. We previously developed a promising nerve conduit manufactured from biodegradable polycaprolactone fumarate (PCLF) for use in peripheral nerve regeneration applications. In the present study, we fabricated conductive PCLF-CNT scaffolds using ultraviolet (UV) induced photocrosslinking. We confirmed the successful incorporation of CNTs into the PCLF-CNT scaffolds which exhibited improved surface roughness compared with plain PCLF by scanning electronic microscopy, transmission electronic microscopy, and atomic force microscopy examinations. The PCLF-CNT substrates also had reduced impedance by electrochemical measurements. Enhanced PC-12 cell growth and differentiation were observed on PCLF-CNT sheets compared with PCLF sheets, indicating the beneficial effects of embedding CNTs into PCLF. Electrical stimulation not only enhanced PC-12 cell proliferation and neurite extension, but also promoted cellular migration and intracellular connections, which are all critical cellular behaviours for nerve regeneration. Overall, this study provides a new promising strategy for using electrically conductive PCLF-CNT nerve scaffolds in regenerative medicine.