Preparation and characterization of poly(trimethylene carbonate) and reduced graphene oxide composites for nerve regeneration

Abstract

Although peripheral nerves are known to have some regenerative abilities, completely separated nerve ends are rarely known to restore function without medical intervention. The main scientific focus for novel treatments of peripheral nerve injury concentrates on a biodegradable nerve guide channel (NGC) that promotes and guides axonal regrowth. Because electrically conductive NGCs promote axon regeneration, we propose a composite material consisting of the polymer poly(trimethylene carbonate) (PTMC) and the conductive filler reduced graphene oxide (rGO). Graphite was oxidized following Hummers' method, exfoliated using sonication and subsequently reduced with hydrazine in order to form thin sheets of rGO. Three‐armed PTMC functionalized with methacrylic anhydride (MA) was dissolved in dispersions of rGO in dimethylformamide with desired rGO contents. After precipitation and solvent casting in chloroform, the films were crosslinked under UV light. The PTMC‐MA/rGO composite films with 0, 0.5, 1, 2 and 4 wt% showed increasing electroconductivity with values up to 6.88 × 10−2 S cm−1. Culturing of PC‐12 cells showed that after initial cell adhesion, the cells proliferated on the surface of the PTMC‐MA/rGO composite films, regardless of the amount of rGO loading. The results imply that these PTMC‐MA/rGO composites show promise toward their use in the fabrication of NGCs. The electrically conductive materials are expected to increase the rate of axonal regeneration, resulting in improved functional recovery of transected peripheral nerves. Copyright © 2016 John Wiley & Sons, Ltd.