Zif-8(Cel)-Modified Peek Implant For Bone Regeneration

The study aims to enhance bone regeneration using a ZIF-8(CEL)-modified PEEK implant for sustained bioactive release and osteoimmunomodulation. The study modified polyetheretherketone (PEEK) via sulfonation (SPEEK) to create a porous surface, followed by dopamine adhesion to immobilize ZIF-8 loaded with celecoxib (ZIF-8(CEL)), forming PEEK@ZIF-8(CEL). Material characterization included SEM, EDS, contact angle, and Zn²⁺/CEL release analysis (ICP-MS/HPLC). In vitro, MC3T3-E1 osteoblasts and RAW 264.7 macrophages were cultured to assess adhesion (SEM), viability (live/dead staining), osteogenic (BMP-6, Runx2) and inflammatory (TNF-α, IL-6) gene expression (RT-qPCR), and mineralization (SBF immersion). In vivo, PEEK@ZIF-8(CEL) was implanted into SD rat cranial defects. Bone regeneration was evaluated via micro-CT (BMD, BV/TV), histology (H&E, Goldner staining), immunohistofluorescence (Runx2, CD31), and nanoindentation for mechanical properties. Statistical analysis used ANOVA and t-tests (GraphPad Prism). Animal protocols were ethically approved. PEEK@ZIF-8(CEL) demonstrated enhanced osteogenic activity and anti-inflammatory effects through sustained release of Zn²⁺ and celecoxib. In vivo studies showed superior bone regeneration with higher bone density (BMD: 0.128 g/cm³) and volume (BV/TV: 72.2%) compared to unmodified PEEK. The material promoted macrophage polarization toward an anti-inflammatory M2 phenotype, improving osseointegration and mechanical strength in rat cranial defects. This study demonstrates the potential of PEEK@ZIF-8(CEL) as a novel repair material for large bone defects, offering a promising alternative in maxillofacial applications.