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The first example of dually synergetic network hydrogel, which has integrated mechanical stretchability, thermal responsiveness, and electrical conductivity, has been constructed by a versatile and topological co-cross-linking approach. Poly( N-isopropylacrylamide) (PNIPAAm) is introduced as the thermally responsive ingredient, and polyaniline (PANI) is selected as the electrically conductive ingredient. PNIPAAm network is cross-linked by double-bond end-capped Pluronic F127 (F127DA). PANI network is doped and cross-linked by phytic acid. These two ingredients are further mechanically interlocked. Due to the integrated multiple functionalities, the topologically co-cross-linked hydrogels, as will be mentioned as F-PNIPAAm/PANI hydrogels, can be fabricated into resistive-type strain sensors. The strain sensors can achieve a gauge factor of 3.92, a response time of 0.4 s, and a sensing stability for at least 350 cycles and can be further applied for monitoring human motions, including motion of two hands, bending of joints, and even swallowing and pulse rate. Moreover, F-PNIPAAm/PANI hydrogels are utilized to construct efficient temperature alertors based on the disconnection of circuits induced by volume shrinkage at high temperature.

Recent emerged antibacterial agents provide enormous new possibilities to replace antibiotics in fighting bacterial infectious diseases. Although abundant types of nanoagents are developed for preventing pathogen colonization, however, rationally design of nonchemotherapic, robust, and clinical‐adaptable nanoagents with tunable bacterial trap and killing activities remains a major challenge. Here, a demonstration of controlling the trap, ablation, and release activities of pathogenic bacteria via stimulus‐responsive regulatory mechanism is reported. First, temperature‐sensitive polymer brush is chemically grown onto carbon nanotube–Fe3O4, whereby the synthesized nanoagents can transfer from hydrophilic dispersion to hydrophobic aggregation upon near‐infrared light irradiation, which thus controls the bacterial trap, killing, and detaching. In turn, the formed aggregations will serve as localized heating sources to enhance photothermal ablation of bacteria. Systematically antibacterial experiments and mouse wound disinfection demonstrate the ultrarobust and recyclable disinfection capability of nanoagents with nearly 100% killing ratio to Staphylococcus aureus. Overall, for the first time, we represent a pioneering study on designing nonchemotherapic and robust dual‐responsive nanoagents that can sensitively and reversibly trap, inactivate, and detach bacteria. We envision that such nanoagents will not only have potential applications in pathogenic bacteria prevention but also provide a new pathway for wound disinfection, implant sterilization, and also live bacteria transportation.

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