NIR-Plasmon Enhanced MXene/Fe-MOFs Composite Scaffold for Synergistic Chemodynamic-Photothermal Antibacterial Therapy in Bone Implants

Bacterial infection remains a critical challenge in bone stent implantation, often leading to implantation failure. This study proposes a synergistic antibacterial strategy combining photothermal therapy and plasmon-enhanced CDT within a 3D-printed bioactive scaffold. Porous polylactic acid bone scaffolds incorporated with Ti₃C₂-MXene/Fe-MOFs nanocomposites were fabricated using selective laser sintering technology. This approach not only ensures precise architectural control and uniform dispersion of MXM but also maintains suitable porosity and compressive strength for bone regeneration. Under near-infrared irradiation, Ti₃C₂-MXene generates localized surface plasmon resonance, producing hot electrons that enhance the Fenton reaction activity of Fe-MOFs for improved ROS generation, while simultaneously delivering photothermal effects through NIR absorption. Systematic investigations including finite element simulations, XPS analysis, and electrochemical characterization reveal that LSPR-induced electron transfer reduces the activation energy of the Fenton process, significantly boosting antibacterial efficiency. This work not only establishes a mechanism for NIR-enhanced nanozyme systems but also advances the development of 3D-printed multifunctional implants with spatially tailored antibacterial capabilities for orthopedic applications.