Conductive core-sheath nanofibers and their potential application in neural tissue engineering

Conductive core-sheath nanofibers are prepared by a combination of electrospinning and aqueous polymerization. Specifically, nanofibers electrospun from poly(ε-caprolactone) (PCL) and poly(1-lactide) (PLA) are employed as templates to generate uniform sheaths of polypyrrole (PPy) by in-situ polymerization. These conductive core-sheath nanofibers offer a unique system to study the synergistic effect of different cues on neurite outgrowth in vitro. It is found that explanted dorsal root ganglia (DRC) adhere well to the conductive core-sheath nanofibers and generate neurites across the surface when there is a nerve growth factor in the medium. Furthermore, the neurites can be oriented along one direction and enhanced by 82% in terms of maximum length when uniaxially aligned conductive core-sheath nanofibers are compared with their random counterparts. Electrical stimulation, when applied through the mats of conductive core-sheath nanofibers, is found to further increase the maximum length of neurites for random and aligned samples by 83% and 47%, respectively, relative to the controls without electrical stimulation. Together these results suggest the potential use of the conductive core-sheath nanofibers as scaffolds in applications such as neural tissue engineering.