PLGA/β-TCP/ICT composite scaffold incorporating MXene (Ti3C2Tx) promotes osteogenesis through near-infrared-mediated mild photothermal therapy

Porous poly (lactic-co-glycolic acid)/β-tricalcium phosphate icaritin (PTI) scaffold is an ideal alternative for repairing bone defects, but their osteoinductive activity are limited. In this study, we fabricated a MXene (Ti₃C₂T_x) composite PTI (TPTI) scaffold and evaluated its characterization. We co-cultured the scaffolds with rat bone marrow mesenchymal stem cells to access the biocompatibility and osteogenic potential of the TPTI scaffold under on-demand near-infrared (NIR) irradiation. Then TPTI scaffold was implanted in a femoral condyle defect model to evaluate the osteogenic properties by micro-computed tomography, histological and immunohistochemical analysis. The results of experiments reveal that MPTI scaffold has appropriate spatial structure, suitable mechanical strength, and superior photothermal properties. It can maintain the temperature at 42.0 ± 0.5 °C and promote the release of ICT from scaffold under 0.85 W cm⁻² NIR irradiation. Furthermore, the scaffold is biocompatible and could promote cell proliferation, osteogenic differentiation, and biomineralization in vitro, as well as the repair of bone defects in vivo, and its effect is further enhanced under NIR irradiation. In conclusion, the MPTI scaffold has the potential to be applied in bone defects repairing, and its osteogenic property can be promoted under NIR irradiation through mild photothermal therapy.