Polyetheretherketone surface modification by lithium-doped bioglass nanospheres to regulate bone immunity and promote osseointegration

Polyetheretherketone (PEEK) is a frequently utilized orthopedic implant material in clinical settings. However, the adverse inflammatory and immunological reactions due to the PEEK surface after implantation often cause poor osseointegration and thereby hinder its clinical utility. To improve osseointegration and enhance the success rate of PEEK implants, the surface can be biofunctionalized to be immunomodulatory. Consequently, in this study, lithium-doped bioglass nanospheres (Li/BGs) was coated on the sulfonated PEEK surface. Furthermore, we assessed the anti-inflammatory potential of the biofunctionalized PEEK implants and their impact on osteogenesis. In our study, it was observed that the in vitro biofunctionalized PEEK surface exhibited enhanced osteogenesis and immunomodulatory osteogenesis properties, while also effectively suppressing the acute inflammatory response initiated by macrophages. Furthermore, our in vivo experiments demonstrated that the biofunctionalized PEEK surface contributed to improved osteogenesis properties and mitigated the formation of fibrous capsules. Therefore, the in vitro and in vivo results demonstrated that PEEK surface modification with Li/BGs not only changed the disadvantage of being bioinert on the surface but also endowed it with osteoimmunomodulatory regulation and bone-promoting properties. Thus, the biofunctionalized PEEK may be a promising candidate for use as an orthopedic implant in clinical settings.