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Antibacterial photocatalytic therapy (APCT) is one of the most promising non‐antibiotic treatment strategies for biofilm‐infected wounds and inflammation caused by drug‐resistant bacteria. However, it still faces issues such as inadequate single antibacterial capacity and lack of antioxidant capacity. In this study, a Z‐scheme heterojunction (Bi2S3‐X@PDA) is designed using a polydopamine (PDA) shell firmly anchored to the surface of sulfur vacancy‐rich bismuth sulfide nanorods (Bi2S3‐X NRs). Under near‐infrared light and hydrogen peroxide, Bi2S3‐X@PDA significantly improves the photocatalytic efficiency of reactive oxygen species generation and shows a nearly 100% broad‐spectrum antibacterial effect against multiple bacterial strains and bacterial biofilms in vitro. Interestingly, the antioxidant activity of the PDA shell in Bi2S3‐X@PDA remarkably downregulates the expression of pro‐inflammatory factors and promotes macrophage reprogramming toward the proregenerative M2 phenotype. In a mouse wound model of methicillin‐resistant Staphylococcus aureus biofilm infection, Bi2S3‐X@PDA effectively eliminates drug‐resistant bacterial biofilms through APCT/mild photothermal therapy, while reducing inflammation in normal tissues and regulating the immune microenvironment, thereby promoting rapid wound healing. Overall, this light‐controlled treatment strategy, which provides both antibacterial and anti‐inflammatory functions, is a reliable tool for combating biofilm infection and inflammation caused by drug‐resistant bacteria. [ABSTRACT FROM AUTHOR]

The hypoxic tumor microenvironment (TME) significantly affects cancer treatment. Conventional chemotherapeutic agents cannot effectively target hypoxic tumor tissue, which decreases efficacy and results in severe toxic side effects. To alleviate this problem, a self‐driving biomotor is developed by functionalizing MCDP nanoparticles containing calcium peroxide and doxorubicin (DOX) loaded onto polydopamine‐coated metal–organic frameworks（MOF）, with the anaerobic Bifidobacterium infantis (Bif) for synergistic chemotherapy and chemodynamic therapy (CDT) against breast cancer. The materials of institute Lavoisier (MIL) frameworks + CaO2 + DOX + polydopamine (MCDP)@Bif biohybrid actively targets hypoxic regions of solid tumors via the inherent targeting ability of Bif. Once it has accumulated in the tumor tissue, MCDP generates hydroxyl radicals through the enhanced Fenton‐type reactions between Fe2+ and self‐generated hydrogen peroxide in the acidic TME. The disruption of Ca2+ homeostasis and resulting mitochondrial Ca2+ overload triggers apoptosis and enhances oxidative stress, promoting tumor cell death. The results found that the DOX concentration in MCDP@Bif‐treated tumors is 3.8 times higher than that in free‐DOX‐treated tumors, which significantly prolongs the median survival of the tumor‐bearing mice to 69 days and reduces the toxic side effects of DOX. Therefore, the novel bacteria‐driven drug delivery system is highly effective in achieving synergistic chemotherapy and CDT against solid tumors. [ABSTRACT FROM AUTHOR]

Minimizing drug leakage in systemic circulation, synchronizing the in vivo fate of multiple drugs, and precisely controlling tumor locoregional drug release, remain challenging for nanomedicine‐based cancer therapy. Here, a reactive oxygen species (ROS)‐responsive camptothecin (CPT) prodrug delivery system (MPEG‐(TK‐CPT)‐PPa) is developed, in which CPT and photosensitizer pyropheophorbide‐a (PPa) are concurrently conjugated to the same poly(ethylene glycol) methyl ether (MPEG) via ROS‐responsive thioketal (TK) and lipid linkage. The synthesized MPEG‐(TK‐CPT)‐PPa conjugate self‐assembles to form nanoparticles (NPs) (43.6 ± 0.8 nm) in solution. The covalently conjugated prodrug prevents drug leakage during systemic circulation and synchronizes the in vivo distribution of the two drugs. The generated fluorescence signal of PPa helps precisely track and locate the NPs at tumor sites. Under the guidance of imaging, a near‐infrared laser locally irradiates tumor tissue upon reaching the strongest fluorescence. The ROS generated by PPa not only cleaves the TK linkage and then triggers locoregional, controllable and on‐demand CPT release, but also exhibits cytotoxic effects on tumor cells. Thus, CPT‐mediated chemotherapy and PPa‐induced photodynamic therapy lead to the combined and enhanced suppression of tumor growth. Accordingly, such laser‐triggered, localized, controllable, and on‐demand drug release systems may provide an alternative option for CPT formulations. [ABSTRACT FROM AUTHOR]