Three-dimensional porous reduced graphene oxide/hydroxyapatite membrane for guided bone regeneration

The guided bone regeneration (GBR) membrane is intended to provide sufficient space for alveolar bone regeneration and meanwhile prevent the invasion of gingival epithelium. In this study, three-dimensional porous reduced graphene oxide/hydroxyapatite (3D rGO/HA) membrane with two different sides was prepared using a two-step electrochemical method. One side of this composite membrane facing the bone defect was formed by 3D porous rGO with HA deposited on the frame of the 3D structure, and the other side of the membrane presented a dense 2D rGO surface to prevent the invasion of the gingival epithelium. The morphology, phase composition, and physical properties of the 3D rGO/HA composite membrane were characterized. Then the cell morphology, viability, and proliferation of pre-osteoblasts (MC3T3-E1 cells) on the 3D porous structure surface of membranes were evaluated and alkaline phosphatase (ALP) secretion as an indication of osteogenic differentiation was also investigated. Meanwhile, cell morphology, viability, and proliferation of HUVEC and L929 cells on the dense structure surface were examined. Finally, a cranial defect model of rat was employed to evaluate the effect of 3D rGO/HA as a GBR membrane in vivo. The results revealed the 3D rGO/HA membrane had good biocompatibility for MC3T3-E1 and HUVEC cells and could significantly enhance ALP secretion. Furthermore, this membrane also promoted the repair of calvarial defects in vivo. These results demonstrated that 3D porous rGO/HA composite membrane with a porous side and another dense side represents great application potential as an ideal GBR membrane.