Magnesium bioactive glass hybrid functionalized polyetheretherketone with immunomodulatory function to guide cell fate and bone regeneration

Polyetheretherketone (PEEK) is being increasingly recognized as a highly promising polymer implant in orthopaedics due to its advantageous biocompatibility, favorable processability, and radiation resistance. Nonetheless, the long-term application of PEEK implants in vivo faces challenges due to unfavorable post-implantation inflammatory and immune reactions, which result in suboptimal osseointegration rates. Hence, biofunctionalizing the surface of PEEK implants emerges as a viable strategy to enhance osseointegration and increase the success rate. In this study, we developed a multifunctional PEEK implant through the in-situ incorporation of chitosan-coated bioactive glass nanoparticles (BGNs). This approach can impart immunomodulatory properties and enhance the potential for osseointegration. The resulting biofunctionalized PEEK material exhibited multiple beneficial effects. For instance, it facilitated M2 phenotypic polarization of macrophages, diminished the expression of inflammatory factors, and enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. Moreover, it exhibited an improved capacity for osseointegration when tested in vivo. The findings of the experiment highlighted the pivotal and complex role of the biofunctionalized PEEK implant in maintaining typical bone immunity and metabolism. The study proposes that the application of chitosan-BGNs presents a straightforward approach to developing multifunctional implants with the ability to promote biomineralization and immunomodulation, specifically tailored for orthopaedic applications.