Biofunctionalized carbon nanotubes as a smart nanomaterial immobilized on a tissue culture polystyrene plate for promoting neuronal outgrowth

Abstract Carbon nanotubes (CNTs) offer attractive attributes that are useful in innovative biomaterial design for neuroscience research due to their nanoscale features, modifiable chemical functionalities, and tunable electrical properties. In this study, we developed a simple and cost-effective fabrication method for advanced surface-modified cell culture system by immobilizing biofunctionalized CNTs onto commercial tissue culture polystyrene plates. This active substrate was examined to understand the effects of electrical, morphological, and chemical interactions with CNT-entrapped drug, bpV as a PTEN inhibitor, on the neuronal differentiation of PC-12 cells. Compared to control, the percentage of neuronal cells stimulating neurites increased by a factor of 4.0, 7.8, and 10.0, when cultured on immobilized carboxylated CNT substrate, PEGylated CNT substrate, and PEGylated CNT substrate in the presence of 10 nM bpV, respectively. The bpV-loaded CNT substrates down-regulated the expression of PTEN and up-regulated the Akt/ERK signaling pathway, thereby providing the mechanism for the improved neuronal outgrowth. These results highlight the promise of the biofunctionalized CNTs as the electroactive and drug-releasing smart nanomaterials for promoting neuronal outgrowth and suggest their potential utility in future neural regeneration applications.