In vitro and in vivo characterization of graphene oxide coated porcine bone granules

Graphene oxide (GO) demonstrated to improve the wound healing properties of materials intended for bone replacement. The main objective of this study was the setting up of a simple and effective procedure for the production of GO-coated porcine bone (PB) granules and the characterization of the obtained material in order to improve its properties by exploiting chemical, physical, biological and mechanical features that the GO coating could confer to pre-formed PB granules. The obtained coating was homogeneously distributed on PB granule surface and demonstrated to confer PB an increased resistance to fracture load. Biological analyses evidenced no toxic effects of GO-coated PB samples on primary human gingival fibroblasts, and no inflammatory response around the grafted particles when implanted in vivo on a sheep model although GO-coated PB samples did not appear to improve new bone formation efficacy compared with the control within the investigated time. A small loss of GO was however detected, indicating the opportunity to investigate less GO concentrated samples. In conclusion, this study presents a novel and low cost approach to the development of functionalized biomimetic hybrid materials which can be applied to other bone substitute materials in order to improve their performances.