Fig. 1.

Fabrication of three types of exosomes: BMSC-Exos, BMSC-Fe₃O₄-Exos and BMSC-Fe₃O₄-SMF-Exos. (*) p < 0.05, (***) p < 0.001. a Schematic illustration of magnetic stimulation using Fe₃O₄ nanoparticles and SMF. b CCK8 assay for the proliferation of BMSCs cultured in the presence of various concentrations of Fe₃O₄ nanoparticles combined with exposure to SMFs of different strengths. c Proliferation of BMSCs treated with the optimal working concentration (50 µg/mL) of Fe₃O₄ nanoparticles and exposed to SMFs of different strengths. d TEM images of the Fe₃O₄ and BMSCs. The dotted yellow box indicates the internalization of Fe₃O₄ by BMSCs, and the red arrows indicate the Fe₃O₄ nanoparticles