Preparation and biological properties of a graphene oxide/silk fibroin barrier membrane loaded with simvastatin

A graphene oxide/silk fibroin (GO/SF) barrier membrane loaded with simvastatin (SIM) was prepared by a freeze-drying method. The biocompatibility of the barrier membrane in vitro and its applicability in guided bone regeneration were investigated. The morphology,structure and the drug release behavior of the membrane were characterized by SEM, XRD and UV-spectroscopy. Laser confocal microscopy and CCK-8 tests were used to evaluate the attachment and proliferation of MC3T3-E1 dermal cells. Defective skulls of Sprague Dawley rats were covered with four membranes (GO/SF/SIM membrane, GO/SF membrane, SF/SIM membrane and SF membrane) and their effectiveness for bone regeneration was evaluated. Results indicated that the GO/SF/SIM membrane had a double-layer (dense surface and porous inside) and stable silk Ⅱ structure. SIM was continuously released from the barrier membrane over 15 days. The GO/SF membrane supported the attachment, growth and proliferation of MC3T3-E1 cells. The GO/SF/SIM exhibited the best bone repairing ability among the four membranes and a better biocompatibility in vitro than the GO/SF. The local application of GO had no damage to important organs (liver, spleen and kidney) of the rats in the short-term observation.