At present, surgery is one of the main treatments for
bone tumor.
However, the risk of recurrence and the large area of bone defects
after surgery pose a great challenge. Therefore, a Janus-inspired
core–shell structure bone scaffold was designed to achieve
the self-programmed release of melatonin at different concentrations,
clearing the residual tumor cells at early stage after resection and
promoting bone repair later. The layered differential load designs
inspired by Janus laid the foundation for the differential release
of melatonin, where sufficient melatonin inhibited tumor growth as
low dose promoted osteogenesis. Then, the automatically programmed
delivery of melatonin is achieved by the gradient degradation of the
core–shell structure. In the material characterization, scanning
electron microscopy revealed the core–shell structure. The
drug release experiment and in vivo degradation experiment
reflected the programmed differential release of melatonin. In the
biological experiment part, in vivo and in
vitro experiments not only confirmed the significant inhibitory
effect of the core–shell hydrogel scaffold on tumor but also
confirmed its positive effect on osteogenesis. Our Janus-inspired
core–shell hydrogel scaffold provides a safe and efficient
means to inhibit tumor recurrence and bone repair after bone tumor,
and it also develops a new and efficient tool for differential and
programmed release of other drugs.