A hemostatic carbon foam prevents postoperative tumor recurrence and metastasis via NIR-II light triggered drug release and hyperthermia

• A hemostatic carbon foam was developed to prevent cancer recurrence and metastasis. • The carbon foam gradually degraded in vivo and demonstrated good biocompatibility . • We report the first use of carbon foam as a hemostatic and photothermal implant. Postoperative tumor recurrence and metastasis have long been challenging issues for cancer patients. In this work, we have developed an implantable carbon foam that uniquely integrates second near-infrared (NIR-II) light triggered drug release, photothermal therapy, and rapid hemostasis by cross-linking a drug-loaded agarose gel with porous carbon foam (DOX@AG/CF). The functionalized carbon foam possessed outstanding photothermal conversion performance, achieving a rapid temperature rise exceeding 108 °C in just 4 s under a low power intensity of 0.25 W cm −2 with 1064 nm laser irradiation, thereby minimizing the risk of severe skin damage. Furthermore, DOX@AG/CF can regulate the release of the loaded drug though the temperature-responsive agarose gel, which synergistically facilitates postoperative therapy. As a result, such all-in-one gel/carbon foam composite, integrating postoperative hemostasis, photothermal therapy and photocontrolled chemotherapy, can effectively eradicate residual tumor cells and prevent the recurrence and metastasis of cancer in vivo . More importantly, the implanted carbon foam demonstrated excellent degradability and biocompatibility , presenting great potential in clinical application.