Real-life wearable electronics with long-term stable sensing performance are of significant practical interest to public. Wearable pressure sensors with washable, comfortable, breathable, and stable sensing ability are a key requirement to meet the desire. However, effects of ubiquitous ambient moisture and intrinsic defects of current capacitive sensing materials are two factors leading to unstable sensing performance of current pressure sensors. Existing ionic liquid-based materials (i.e., ionic hydrogel, ionic film, or ionic/ elastomers composite) have been used for efficient capacitive pressure sensing but are highly sensitive and especially affected by moisture. In this work, we introduce a washable capacitive pressure-sensing textile based on the use of a hydrophobic poly(ionic liquid) nanofibrous membrane (PILNM) with good mechanical properties and satisfactory moisture proof sensing performance. The PILNM membranes possessing rich ions and microporous structures are novel ideal polymeric dielectric materials for amplification of signals with negligible stimulations. Moreover, the PILNMs exhibit very high stable sensing signals under moisture interference (up to 70% relative humidity) and repeated washings (more than 10 washings), especially suitable for wearable electronics. Notably, the PILNM-based wearable pressure-sensing textiles offer high sensitivity for low pressure and bent chord length changes with a low-pressure detection limit even under harsh deformations. Owing to the superior performance, the PILNM-based wearable pressure-sensing textiles are comfortable to wear and suitable for monitoring different human motions and pulse vibrations at various body positions. Meanwhile, the assembled multiple wearable pressure-sensing array can spatially map the contact area of the pressure stimuli and synchronously reflect finger movements.

There is a critical need for new efficient solutions to purify and disinfect water from source to point-of-use, especially for the water contaminated by pathogenic microbes. Traditional disinfection technologies are chemically intensive and limited, either by biofouling or by the irreversible consumption of disinfectants. Herein, we present a scalable methodology to create biocidal and rechargeable nanofibrous membranes (BNF membranes) by combining N-halamine antimicrobial agent with electrospun nanofibers. Our method allows intrinsically rechargeable N-halamine moieties to covalently incorporate into nanofibers with high biocidal activity and durability. The resulting BNF membranes exhibit integrated properties of high porosity, large surface area, robust mechanical strength, super hydrophilicity, rechargeable chlorination capability (>3000 ppm), and high bactericidal efficacy (99.9999% contact-killing), which enabled the BNF membranes effectively disinfect bacteria-contained water by direct filtration, with promising high durability and fluxes (10000 L m −2 h −1 ). The successful synthesis of BNF membranes also provides a versatile platform for exploring the antimicrobial N-halamine materials in a self-supporting, structurally adaptive, and nanofibrous form.

Antimicrobial polymeric films that are both mechanically robust and function renewable would have broad technological implications for areas ranging from medical safety and bioengineering to foods industry; however, creating such materials has proven extremely challenging. Here, a novel strategy is reported to create high-strength N-halamine incorporated poly(vinyl alcohol-co-ethylene) films (HAF films) with renewable antimicrobial activity by combining melt radical graft polymerization and reactive extrusion technique. The approach allows here the intrinsically rechargeable N-halamine moieties to be covalently incorporated into polymeric films with high biocidal activity and durability. The resulting HAF films exhibit integrated properties of robust mechanical strength, high transparency, rechargeable chlorination capability (>300 ppm), and long-term durability, which can effectively offer 3-5 logs CFU reduction against typical pathogenic bacterium Escherichia coli within a short contact time of 1 h, even at high organism conditions. The successful synthesis of HAF films also provides a versatile platform for exploring the applications of antimicrobial N-halamine moieties in a self-supporting, structurally adaptive, and function renewable form.

Enzyme-linked immunoassay (ELISA) is highly specific and selective towards target molecules and is convenient for on-site detection. However, in many cases, lack of high sensitivity makes it hard to reveal a significant colorimetric signal for detecting a trace amount of target molecules. Thus, analytical instruments are required for detection, which limits the application of ELISA for on-site detection. In the present study, a highly sensitive and naked-eyed detectable colorimetric biosensor for chloramphenicol (CAP) was prepared by incorporating ELISA onto surfaces of microporous and nanofibrous membranes. The high specific surface areas of the nanofibers significantly increased the number of antibodies covalently linked onto the fiber surfaces and binding capacity of the sensor with antigens present in a sample. With such an integration, the sensitivity of the ELISA sensor was dramatically increased, and a trace number of targets could reveal a naked-eye detectable color. The immunoassay sensor exhibited a significant naked-eye distinguishable color to chloramphenicol (CAP) at 0.3 ng/ mL. The successful design and fabrication of the nanofibrous membrane immunoassay sensor provide new paths towards the development of on-site inspection sensors without the assistance from any instrument.

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