3D printed PEEK scaffolds functionalized with composite hydrogel coatings incorporating magnesium nanoparticles/BMP-2 microspheres for enhanced osteogenesis

Polyetheretherketone (PEEK) is a promising orthopedic implant material; however, its application is limited by biological inertness and high hydrophobicity, which lead to poor osseointegration. Conjugating growth factors with osteogenic activity to the surface of PEEK scaffolds provides a strategy to improve osteoconductivity, but this approach still faces limitations such as unfavorable release kinetics and the risk of inflammation. Herein, we present a microsphere-integrated composite hydrogel coating for 3D printed PEEK scaffolds fabricated via droplet microfluidics and photopolymerization, allowing co-delivery of bone morphogenetic protein-2 (BMP-2) and magnesium to boost osteogenic performance. The functional coatings exhibit enhanced cell adhesion and osteogenic differentiation while reducing pro-inflammatory levels compared to using BMP-2 alone in vitro . In vivo studies confirm that the coatings promoted bone formation and maturation. Overall, this study provides a new strategy for PEEK scaffold modification and bone tissue engineering.