Dual Roles of Graphene Oxide in Chondrogenic Differentiation of Adult Stem Cells: Cell‐Adhesion Substrate and Growth Factor‐Delivery Carrier

Here, it is shown that graphene oxide (GO) can be utilized as both a cell‐adhesion substrate and a growth factor protein‐delivery carrier for the chondrogenic differentiation of adult stem cells. Conventionally, chondrogenic differentiation of stem cells is achieved by culturing cells in pellets and adding the protein transforming growth factor‐β3 (TGF‐β3), a chondrogenic factor, to the culture medium. However, pellets mainly provide cell‐cell interaction and diffusional limitation of TGF‐β3 may occur inside the pellet both of these factors may limit the chondrogenic differentiation of stem cells. In this study, GO sheets (size = 0.5–1 μm) were utilized to adsorb fibronectin (FN, a cell‐adhesion protein) and TGF‐β3 and were then incorporated in pellets of human adipose‐derived stem cells (hASCs). The hybrid pellets of hASC‐GO enhanced the chondrogenic differentiation of hASCs by adding the cell‐FN interaction and supplying TGF‐β3 effectively. This method may provide a new platform for stem cell culture for regenerative medicine.