Analysis of neural cell behaviour on anisotropic electrically conductive polymeric biodegradable scaffolds reinforced with carbon nanotubes

The advent of biocompatible and biodegradable scaffolds has opened up a plethora of possibilities in neural tissue engineering. An emerging approach to overcome some existing drawbacks of neural scaffold design and functioning is a natural conductive polymeric scaffold. It is analogous to the extracellular matrix and provides an environment conducive to neural growth. This study focuses on the fabrication of soft polymeric neural scaffold, reinforced with multi-walled carbon nanotubes (MWCNTs) in a chitosan matrix, for directional neuronal growth. The scaffolds were fabricated by varying the nanofiller content as 0.5, 1.0 and 2.0. wt%, which were aligned in the chitosan matrix by an alternating bias electric field and compared with their random counterpart. The uniform distribution of the nanofillers in the matrix, good combinatorial bonding, and the directional alignment of the MWCNTs resulted in enhancement of mechanical properties and electrical conductivity in comparison to scaffolds with randomly arranged reinforcements. Additionally, the degradation kinetics of the fabricated scaffolds was tuned to the regeneration regime of peripheral nerves. After physical characterization, the biocompatibility of the designed scaffolds was evaluated by culturing HT-22 neuronal cells on the scaffolds. Along with biocompatibility, the suitability of anisotropic conductivity of the scaffolds was evaluated by the directional growth of cells cultured on aligned MWCNT–chitosan scaffold. The preferential direction of neurite growth achieved on chitosan-aligned MWCNT films and the improved mechanical and electrical properties in the MWCNT alignment direction are very encouraging for their potential use in neural tissue engineering.