▎ 摘　　要

Redox-modulating ceria nanoparticles can impart bioactivity to biodegradable polymers for tissue regeneration but are limited by poor dispersion in the polymer matrix. Toward the development of biodegradable multifunctional biomaterials, cerium oxide (ceria)-decorated graphene-based hybrid nanoparticles were used as nanofillers in a polyurethane matrix. The polyurethane was synthesized using olive oil-based polyol to impart degradability to the composite. Hybrid nanoparticles consisting of ceria anchored on graphene sheets were synthesized by the hydrothermal process. X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy confirmed the anchoring of ceria nanoparticles on the graphene sheets. Polyurethane composites were prepared by in situ polymerization. Hybrid nanoparticle-infused composites showed uniform dispersion, unlike the agglomerated particles in ceria-infused composites. The hybrid nano composite showed improved mechanical properties compared to the ceria nanocomposite. The nanocomposite was nontoxic to pre-osteoblasts. The polyurethane demonstrated enhanced radical-scavenging potential after adding the hybrid nanoparticles in contrast to a neat polymer or graphene oxide-infused composite. The cells exhibited improved osteogenic differentiation on the hybrid composites than on the neat polyurethane or the GO-composite. Thus, the graphene and ceria in the hybrid particles synergistically render multifunctional properties to polyurethanes for potential application in bone tissue regeneration.