In vivo compatibility of graphene oxide with differing oxidation states.

Graphene oxide (GO) is suggested to have great potential as a component of biomedical devices. Although this nanomaterial has been demonstrated to be cytocompatible in vitro, its compatibility in vivo in tissue sites relevant for biomedical device application is yet to be fully understood. Here, we evaluate the compatibility of GO with two different oxidation levels following implantation in subcutaneous and intraperitoneal tissue sites, which are of broad relevance for application to medical devices. We demonstrate GO to be moderately compatible in vivo in both tissue sites, with the inflammatory reaction in response to implantation consistent with a typical foreign body reaction. A reduction in the degree of GO oxidation results in faster immune cell infiltration, uptake, and clearance following both subcutaneous and peritoneal implantation. Future work toward surface modification or coating strategies could be useful to reduce the inflammatory response and improve compatibility of GO as a component of medical devices.