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-<i>x</i>) was synthesized <i>via</i> a deoxidation reaction and was shown to exhibit excellent photothermal performance. Moreover, a composite based on polyetheretherketone (PEEK) containing HfO_2-<i>x</i> (PBHC) was fabricated and displayed good photothermal performance that effectively ablated the tumor cells and eradicated bacteria <i>in vitro</i> under 808 nm NIR laser irradiation. Moreover, the PBHC with good photothermal performance exhibited excellent ability for the treatment of tumors and infection <i>in vivo</i>. Further, PBHC significantly boosted the osteoblastic differentiation of bone mesenchymal stem cells <i>in vitro</i> and promoted bone regeneration <i>in vivo</i> due to the osteogenic activity of HfO_2-<i>x</i>. 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.