Adhesion and differentiation of human mesenchymal stem cells on plasma-functionalized graphenes with different feeding gases

Surface functionalisation of graphene layer has been investigated to improve the efficiencies in bio-applications such as stem cell differentiation or protein sensing. Plasma treatment can induce various functionalities on graphene surface simply by changing feeding gas. In this study, the surface chemistry of graphene is modified by plasma treatment using three different feeding gases of H-2, N-2, and O-2. The effects of differential functionalisation are examined by the adsorption of fibronectin and the adhesion, proliferation, and differentiation of human mesenchymal stem cells. Fibronection adsorption is enhanced on the N-2 plasma-treated graphene, but it is not clear on the others. hMSCs adhesion is broadened on all of the plasma-treated graphene substrates, especially on the N-2 plasma-treated one. H-2 plasma treatment enhances cell proliferation and osteogenic differentiation, and N-2 and O-2 plasma treatments show a tendency of heterogeneous differentiation to osteoblasts and myoblasts. Different responses of stem cell adhesion, proliferation, and differentiation depending on the plasma-treated graphene surface indicate the importance of highly specific surface functionality in stem cell engineering. (C) 2014 Elsevier Ltd. All rights reserved.