In recent years, wearable and flexible sensors have attracted considerable research interest and effort owing to their broad application prospects in wearable devices, robotics, health monitoring, and so on. High-sensitivity and low-cost pressure sensors are the primary requirement in practical application. Herein, a convenient and low-cost process to fabricate a bionic fish-scale structure poly(dimethylsiloxane) (PDMS) film via air/water interfacial formation technique is presented. High-sensitivity flexible pressure sensors can be constructed by assembling conductive films of graphene nanosheets into a microstructured film. Thanks to the unique fish-scale structures of PDMS films, the prepared pressure sensor shows excellent performance with high sensitivity (-70.86% kPa). In addition, our pressure sensors can detect weak signals, such as wrist pulses, respiration, and voice vibrations. Moreover, the whole process of pressure sensor preparation is cost-effective, eco-friendly, and controllable. The results indicate that the prepared pressure sensor has a profitable and efficient advantage in future applications for monitoring human physiological signals and sensing subtle touch, which may broaden its potential applications in wearable devices.

Lubricant-infused surface(s) (LIS) bioinspired by the Nepenthes pitcher plant are receiving enormous attention owing to their excellent hydrophobicity as well as their self-healing ability. Thus, they have been applied as anticorrosion coatings. However, the loss of lubricant mediated by vapor or other liquids deteriorates their functions. Herein, we introduce a lubricant-inserted (sandwiched) microporous triple-layered surface (LIMITS) that prevents the sudden loss of lubricant. The sandwiched lubricant gradually self-secretes toward the surface, resulting in long-term stability even under water. The LIMITS prevented the corrosion of the Fe plate for at least 45 days, which is much superior to a conventional LIS coating. This work opens an avenue for the application of slippery coating materials that are stable under water and will also promote the development of anticorrosion coating in various industries.

Industrial oil spills in various bodies of water is a worldwide environmental problem that requires effective oil absorbents with remote controllability, which would be a clear improvement upon currently used technologies. One approach for adding remote controllability is embedding magnetic particles into the oil absorbent materials; however, there are currently few reports of magnetic oil absorbents. Most of these are prepared through multistep processes or using hazardous materials, which inhibits their practical use. In this study, we introduce a singlestep dipping method to simultaneously provide both magnetic and hydrophobic/oleophilic functions to melamine foam by combining hydrophobic flexible copolymer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and magnetic Fe 3 O 4 nanoparticles synthesized by a method suitable for mass production. The as-fabricated coating performs effectively for oil collection of oil spilled on water, and the movement of the foam on the water's surface can be effectively controlled under magnetic field without touching it directly. Also, the coating is capable of regenerating its oil-absorbing property by being wrung out after the initial absorption owing to its flexibility and separation of oil in a water-in-oil emulsion. Such a simple method for the creation of multifunction material could potentially be helpful for the development of commercial remediation materials.

The cell manipulation technique using thermoresponsive polymers is currently attracting much attention for applications in the medical field. To achieve arbitrary and accurate cell control, it is necessary to intensely research fibronectin behavior. A smart surface, which has thermoresponsive wettability and which can adsorb or desorb fibronectin repeatedly without the presence of cells, was fabricated by an electrospinning method. The fabricated coating changed its structure as the temperature was changed, and this transformation could substitute for the pulling force generated by the cytoskeletal contraction of cells. Moreover, a coated quartz crystal microbalance was able to detect the fibronectin behavior as frequency shifts, which could be used in the estimation of the mass shift with the aid of suitable equations. This coating and measurement system can contribute greatly not only to the development in the medical field centered on biomaterial manipulation technologies, but also to the improvement of medical instruments.

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