Biochemical functionalization of graphene oxide for directing stem cell differentiation

The regeneration of peripheral nerve tissue is crucial in the treatment of peripheral nerve trauma. In recent years, there has been increased focus on biomaterial scaffolds which can deliver stem cells, direct differentiation to the desired lineage and guide tissue regeneration at the site of injury. Here, we report on a graphene oxide (GO) scaffold which has been chemically functionalised to direct the differentiation of adipose-derived mesenchymal stem cells towards the neuroglial lineage and maintain the viability of differentiated cells. A comparison is made between substrates of GO, reduced GO and a peptide (IKVAV) functionalised GO in comparison to standard tissue culture glass. Our results show that the graphene substrates are highly biocompatible, and the IKVAV functionalised substrates are more effective in directing stem cell differentiation towards neuroglial phenotypes compared to glass and other graphene substrates. Furthermore, GO-IKVAV substrates showed increased neuronal attachment and neurons grown on GO-IKVAV sprouted longer neurites. These results suggest that graphene can be rationally functionalised to direct stem-cell differentiation and that functionalised GO could provide a viable scaffold in regenerative therapies of peripheral nerve injuries and disorders.