Constructing Hydroxylated Graphite‐Like Film with Protein Regulation on PEEK for Integrated Bone‐Soft Tissue Therapy

Abstract Polyetheretherketone (PEEK) is commonly used for skull repair, but it involves the risk of poor tissue integration and bacterial infection. Simultaneously endowing PEEK with comprehensive bone and soft tissue integration and antibacterial ability remains a challenge. Herein, a novel hydroxylated graphite‐like layer with protein regulation is constructed on PEEK through a simple hydrogen plasma immersion ion implantation (H‐PIII). The energy transfer between high‐energy hydrogen plasma and molecular chains induces the formation of graphite‐like structures with large conjugated systems on the surface of PEEK. In addition, the enhanced reducibility of hydrogen plasma at high implantation voltage converts oxygen‐containing functional groups on the material into phenolic hydroxyl structures. Simulation and experimental results confirm that the large conjugated systems can increase protein adsorption capacity, and phenolic hydroxyl groups can induce protein exposure to RGD binding sites by changing surface potential. As a consequence, it simultaneously enhances both bone and soft tissue integration capabilities by activating conservative integrin‐related pathways. In addition, the photothermal effect of this film can induce bacterial protein denaturation to kill bacteria under the stimulation of near‐infrared light. This study provides a new idea to endow PEEK polymer implants with integrated antibacterial and bone‐soft tissue therapies.