Mn₃O₄-potentiated bifunctional hydrogel for mild temperature-controlled tumor ablation and osteogenesis

Postoperative bone reconstruction after tumor resection remains challenging due to tumor recurrence and poor osteogenesis. Although photothermal scaffolds can ablate tumors (via high heat) and stimulate bone formation (via mild heat), balancing these effects is difficult-excessive heat damages tissue, while insufficient heat fails to eliminate tumors. Here, we develop an injectable Mn₃O₄-enhanced hydrogel (GM/OD/Mn₃O₄) to address this. Mn₃O₄ nanosheets, firstly synthesized via biomineralization, exhibit high photothermal efficiency and enzyme-mimetic activity (glucose oxidase/peroxidase-like). The hydrogel adapts to irregular defects and releases Mn₃O₄ in acidic tumor microenvironments. Through catalytic cascades, it depletes ATP and inhibits heat shock proteins, overcoming tumor thermoresistance and enabling effective ablation at mild temperatures (43 °C). Lower NIR power (40 °C) further enhances osteogenesis. In vivo, the hydrogel suppresses tumor recurrence while promoting bone regeneration, offering a dual-functional strategy for postoperative bone repair.