Engineering a multiscale multifunctional theragenerative system for enhancing osteosarcoma therapy, bone regeneration and bacterial eradication

Osteosarcoma as an aggressive malignant neoplasm is one of the formidable challenging diseases clinically. The related tumor recurrence, large bone defects, and postoperative bacterial infection after surgical resection of osteosarcoma are pressing problems that still threaten patient health. Herein, a multiscale multifunctional theragenerative system (Fs-NFs-AuPt) is designed based on NiTi alloys for near-infrared-activated photothermal ablation of osteosarcoma, bone repair, and antibacterial. To achieve this aim, first, a useful methodology is proposed that employs temporally shaped femtosecond laser ablation combined with hydrothermal synthesis to fabricate multiscale hierarchical structures (Fs-NFs) consisting of three-dimensional micro-nanostructures (Fs-NiTi) and nanoflower-like structures (NFs) for promoting osteogenicity. Then, AuPt bimetallic nanoparticles as satisfactory photothermal therapy agents and osteoinductive agents are rapidly (only need 30 s) one-step in-situ synthesized on Fs-NFs through ultraviolet photoreduction without any reductant. Fs-NFs-AuPt significantly ablates tumors cells (Saos-2 and MDA-MB-231) in vitro, effectively inhibits osteosarcoma growth in mice, and positively induces the osteogenesis of osteoblasts (MC3T3-E1). Moreover, it exhibits superior antibacterial efficiencies of 99.5% and 99.8% against Staphylococcus aureus and Pseudomonas aeruginosa, respectively. Overall, this work offers a high-efficiency, high-quality, and high-repeatability distinctive integrated fabrication avenue to construct a multiscale multifunctional theragenerative system for osteosarcoma therapy and bone-tissue engineering.