Oxygen vacancy-containing hafnium-dioxide/polyetheretherketone composite with good photothermal performance and bioactivity for treatment of tumors and infection as well as the promotion of pro-osteogenesis†

The surgical treatment of bone tumors generally causes bone defects, whilst postoperative infection and tumor recurrence may also occur. Currently, it is still a huge challenge to design multi-functional biomaterials that both eradicate residual tumor cells and bacteria whilst also promoting osteogenesis. Herein, hafnium oxide with an oxygen vacancy (HfO_2−x) was synthesized via a deoxidation reaction and was shown to exhibit excellent photothermal performance. Moreover, a composite based on polyetheretherketone (PEEK) containing HfO_2−x (PBHC) was fabricated and displayed good photothermal performance that effectively ablated the tumor cells and eradicated bacteria in vitro under 808 nm NIR laser irradiation. Moreover, the PBHC with good photothermal performance exhibited excellent ability for the treatment of tumors and infection in vivo. Further, PBHC significantly boosted the osteoblastic differentiation of bone mesenchymal stem cells in vitro and promoted bone regeneration in vivo due to the osteogenic activity of HfO_2−x. PBHC is a multi-functional biomaterial with good biocompatibility, photothermal performance and pro-osteogenic properties that can overcome the triple challenges of tumor recurrence, bacterial infection and bone defects. In summary, PBHC with tumor/bacteria-eradicating and pro-osteogenesis effects could be applicable for the simultaneous treatment of tumors and infection as well as the repair of bone defects.