Polyetheretherketone microspheres loaded with cerium dioxide nanoparticles mitigate damage from cellular oxidative stress and promote bone repair

Abstract

The imbalance of oxidative and antioxidant effects in the bone repair process can lead to insufficient osseointegration of orthopedic implants and cause failure regeneration. In this study, cerium (IV) sulfate (Ce(SO4)2) was introduced into polyetheretherketone (PEEK) to prepare composite microspheres containing Ce(SO4)2 (Ce(SO4)2/PEEK microspheres). A hydrolysis method assisted by hydrothermal treatment enabled the successful in-situ convertion of Ce(SO4)2 to cerium dioxide nanoparticles (CeO2NPs) which were uniformly loaded in the microspheres and fulfilled a unique “topological” structure on the surface of the microspheres. In addition, CeO2NPs in the PEEK microspheres had catalase-like activity, which reduced the amount of hydrogen peroxide (H2O2) in the micro-environment of bone injury. Concurrently, the CeO2NPs/PEEK microspheres directly promoted cell proliferation and osteogenic differentiation and showed excellent promotion of bone regeneration in a rat-skull-defect repair model. In summary, we prepared CeO2NPs that were uniformly distributed in PEEK microspheres using a hydrothermal method to act as antioxidants and improve the osteogenic activity of PEEK microspheres.

Keywords

• Polyetheretherketone
• Cerium dioxide nanoparticles
• Antioxidant
• Bone regeneration