A bifunctional scaffold with CuFeSe₂ nanocrystals for tumor therapy and bone reconstruction

Bone tumor is one of major challenging issues clinically. After surgical intervention, a few bone tumor cells still remain around bone defects and then proliferate over days. Fabrication of specific biomaterials with dual functions of bone tumor therapy and bone regeneration is of great significance. In order to achieve this aim, we managed to prepare bioactive glass (BG) scaffolds functionalized by the CuFeSe₂ nanocrystals (BG-CFS) by combining 3D printing technique with solvothermal method. During the solvothermal reaction process, CuFeSe₂ nanocrystals could in situ grow on the strut surface of BG scaffolds and thus endow BG scaffolds excellent photothermal performance. The photothermal performance of BG-CFS scaffolds could be well regulated through altering the content of CuFeSe₂ nanocrystals and laser power density when exposed to the near infrared laser (808 nm). The BG-CFS scaffolds could not only effectively ablate the bone tumor cells (Saos-2 cells) in vitro, but also significantly inhibit bone tumor growth in vivo. Moreover, BG-CFS scaffolds could stimulate osteogenic gene expressions of rabbit bone marrow stromal cells (rBMSCs) and finally facilitate the formation of new bone in the bone defects. Our study, for the first time, combined the photothermal performance of semiconductor CuFeSe₂ nanocrystals with the bone-forming activity of bioactive glass scaffolds, which can offer a more extensive horizon for developing novel biomaterials with dual functions of bone tumor therapy and bone regeneration.