Bioadhesives have been used in clinics among the most prospective alternatives to sutures and staples for wound sealing and repairing; however, they generally have inadequate adhesion to wet surfaces, improper mechanical strength, poor hemostasis, and cytotoxicity. To address these challenges, a robust wet tissue adhesive based on collagen and starch materials (CoSt) is designed in this study. CoSt hydrogels integrate the feature of drainage, molecular penetration and strengthen cross-linking similar to mussel, ivy, and oyster glues, which remove interfacial water quickly, reinforce tough dissipation and involve multiple reversible dynamic interactions. Therefore, they form strong adhesion and sutureless sealing of injured tissues, accompanying actuate robust biointerfaces in direct contact with tissue liquids or blood, resolving the crucial impediments with sutures and commercially accessible adhesives. The novel bioadhesive shows repeatable strong wet tissue adhesiveness (62 ± 4.8 KPa), high sealing performance (153.2 ± 35.1 mmHg), fast self-healing ability, excellent injectability, and shape adaptability. For different hemostatic needs in rat models of tail amputation, skin incision, severe liver, abdominal aorta, and transected nerve injuries, the CoSt hydrogel shows better hemostatic efficiency than fibrin glue because of the coordinate efficacy of tough wound sealing property, outstanding red blood cell arresting capability, and the activation of hemostatic barrier membrane. Moreover, in vivo investigation of the skin injury repair of the rat model validate that CoSt hydrogels accelerate wound healing and functional recovery via skin damage/defects. Tough wet adhesion, quick hemostasis, distinguished biocompatibility, suitability to match irregular-shaped target sites, and good wound healing promotion of the CoSt hydrogel makes it a prospective bioadhesive for various biomedical applications.

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High levels of reactive oxygen species (ROS) and inflammation create a complicated extrinsic neural environment that dominates the initial post‐injury period after spinal cord injury (SCI). The compensatory pathways between ROS and inflammation limited the efficacy of modulating the above single treatment regimen after SCI. Here, novel “nanoflower” Mn3O4 integrated with “pollen” IRF‐5SiRNA was designed as a combination antioxidant and anti‐inflammatory treatment after SCI. The “nanoflower” and “pollen” structure was encapsulated with a neutrophil membrane for protective and targeted delivery. Furthermore, valence‐engineered nanozyme Mn3O4 imitated the cascade response of antioxidant enzymes with a higher substrate affinity compared to natural antioxidant enzymes. Nanozymes effectively catalyzed ROS to generate O2, which is advantageous for reducing oxidative stress and promoting angiogenesis. The screened “pollen” IRF‐5SiRNA could reverse the inflammatory phenotype by reducing interferon regulatory factors‐5 (IRF‐5) expression (protein level: 73.08% and mRNA level: 63.10%). The decreased expression of pro‐inflammatory factors reduced the infiltration of inflammatory cells, resulting in less neural scarring. In SCI rats, multifunctional nanozymes enhanced the proliferation of various neuronal subtypes (motor neurons, interneurons, and sensory neurons) and the recovery of locomotor function, demonstrating that the remodeling of the extrinsic neural environment is a promising strategy to facilitate nerve regeneration.