A strategy of 3D-printed Ta4C3 MXenes nanohydroxyapatite/methacryloylated silk fibroin scaffolds for postsurgical management of osteosarcoma.

The postoperative repair of bone tumors remains a significant clinical challenge requiring urgent solutions, and this holds particularly true for regenerating large bone defects, completely removing residual tumor cells, and effectively preventing and controlling postoperative infections. The efficacy of traditional single treatments is limited, as they generally target only one of these challenges. To overcome this dilemma, this study designed a multifunctional composite nanoscaffold by applying Ta4C3 MXenes nanosheets to the surface of a 3D printed nano-hydroxyapatite (nHA)/methacrylated silk fibroin (MASF) composite scaffold through in situ anchoring. 3D printing technology fabricated a porous hierarchical architecture matching the target bone defect, which provides a suitable three-dimensional microenvironment for bone cell adhesion, proliferation, and differentiation. The main inorganic component of natural bone, nHA, was included to promote bone tissue mineralization. Additionally, with good biocompatibility and degradability, MASF acts as the organic matrix and facilitates the stable loading of the Ta4C3 MXenes nanosheets. To be more specific, the introduction of Ta4C3 MXenes nanosheets endows the scaffold with excellent photothermal conversion capabilities, enabling the generation of precise and controllable local high temperatures upon near-infrared light irradiation. This property allows it to efficiently kill residual tumor cells through thermal ablation while also exhibiting excellent broad-spectrum antibacterial activity through its thermal effects. This implantable material integrates bone defect repair, tumor clearance, and anti-infection functions, thereby effectively solving the limitations of traditional single therapies. It also provides new ideas for the clinical treatment of tumor-related bone defects and exhibits great application prospects.