Multifunctional bioactive metal phenolic networks (MPN) with copper ion retardation and dual-peptides for enhanced...

Titanium rods are widely used as orthopedic implants, but their biologically inert surface limits their effectiveness in bone healing. To enhance osseointegration, implants need to be multifunctional, capable of modulating cellular behaviors such as early adhesion, migration, angiogenesis, and bone formation. In this study, copper ion-doped phenolic networks (P/Cu MPNs) were developed as a platform for grafting bioactive peptides (OGP and RGD), terminally coupled with K6 (hexameric lysine), to create a multifunctional bioactive coating (RGD/OGP@P/Cu) aimed at improving osteointegration. The properties of RGD/OGP@P/Cu, including hydrophilicity, chemical composition, morphology, roughness, and mechanical characteristics, were thoroughly characterized using techniques such as XPS, AFM, and SEM. The peptide coating effectively modulates the release of copper ions, and the synergistic effects of copper ions and bioactive peptides promoted cell adhesion, migration, osteogenesis, and angiogenesis in vitro. Furthermore, in a rat bone defect model, RGD/OGP@P/Cu demonstrated promising potential for bone regeneration and osseointegration. This synergistic strategy between peptide and controlled release of metal ions has great potential for application in promoting implant osseointegration in complex biological environments.