Graphene oxide-modified PEEK composites: Properties and applications in orthopaedic repair - A review

Critical-sized bone defect repair remains a major challenge in orthopaedics and tissue engineering. Polyetheretherketone (PEEK) has attracted wide attention due to its excellent mechanical compatibility and radiological transparency; however, its inherent bioinertness and insufficient antibacterial properties restrict its clinical utility. In recent years, the incorporation of graphene oxide (GO) has markedly improved the biological performance of PEEK. GO can increase surface hydrophilicity and roughness, enhance protein/ion adsorption, and promote osteoblast adhesion and differentiation, while simultaneously strengthening antibacterial and immunomodulatory effects without compromising, and in some cases even enhancing, mechanical performance. In vitro studies demonstrate that GO-PEEK stimulates osteogenic gene expression and mineralized nodule formation, while in vivo animal models confirm superior osseointegration and new bone formation compared with controls. Synergistic modifications, such as combination with hydroxyapatite, metallic ions, or antimicrobial peptides, further amplify both osteogenic and antibacterial outcomes. Nevertheless, clinical translation of GO-PEEK remains hampered by challenges including long-term stability, potential particulate-related risks, the dynamic balance between antibacterial and osteogenic functions, and issues of manufacturing scalability, consistency, and sterilization compatibility. Future research should focus on establishing a "structure-property-safety" design paradigm, developing temporally programmed multifunctional strategies, and advancing 3D-printed personalized fabrication, with low-load applications such as alveolar or cranial bone repair as potential pioneer indications. Overall, GO-PEEK composites exhibit significant promise in contexts such as post-tumour bone reconstruction, dental implantation, and spinal or joint implants, and are expected to achieve successful clinical translation under evidence-based validation and standardised manufacturing pathways. The Translational Potential of this Article : The findings of this review highlight the potential of graphene oxide-modified PEEK (GO-PEEK) composites as next-generation orthopaedic biomaterials. By integrating enhanced osteogenic activity, antibacterial efficacy, and immunomodulatory capacity into a mechanically compatible and radiolucent polymer, GO-PEEK offers a multifunctional platform for bone repair. Importantly, its promising performance in vitro and in vivo provides a foundation for translation into clinical contexts such as dental implants, spinal fusion cages, and tumour-related bone defect reconstruction. Addressing challenges in long-term stability, sterilization compatibility, and large-scale manufacturing will be critical to establish a clear regulatory and translational pathway from laboratory research to clinical practice.