Pseudocatalytic Hydrogels with Intrinsic Antibacterial and Photothermal Activities for Local Treatment of Subcutaneous Abscesses and Breast Tumors

Abstract The intimate relationship between bacteria and tumors has triggered a lot of activities in the development and design of bioactive materials to concurrently respond to antitumor and antibacterial demands. Herein, a pseudocatalytic hydrogel (AM‐I@Agar) with intrinsic antibacterial and photothermal activities, synthesized by incorporating prefabricated amylose‐iodine nanoparticles into low‐melting‐point agarose hydrogel, is explored as a bioactive agent for local treatment of subcutaneous abscesses and breast tumors. The AM‐I@Agar hydrogel depicts the ability of pseudocatalytic O 2 generation from H 2 O 2 to alleviate hypoxia. Meanwhile, the AM‐I@Agar hydrogel exhibits temperature self‐regulation features, beneficial for avoiding thermal injury during photothermal therapy owing to thermochromic properties. Upon local injection into a subcutaneous abscess, methicillin‐resistant Staphylococcus aureus is effectively eliminated by the AM‐I@Agar hydrogel, and complete skin recovery is achieved in 8 d, demonstrating much better antibacterial effects compared with penicillin, a small‐molecule antibiotic. AM‐I/5‐FU@Agar hydrogel, obtained after loading 5‐fluorouracil (5‐FU), significantly inhibits tumors in both normal 4T1 tumor‐bearing mice and MRSA‐infected 4T1 tumor‐bearing mice models via a synergistic photothermal‐chemo effect, and shows treatment efficiency superior to that achieved with photothermal therapy or 5‐FU alone. This work provides a concept for the design and development of bioactive agents for potential management of bacteria‐associated cancer.