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Droplet arrays show great significance in biosensing and biodetection because of low sample consumption and easy operation. However, inevitable water evaporation in open environment severely limits their applications in time‐consuming reactions. Herein, inspired by the unique water retention features of leaves, it is demonstrated that an open droplet array on patterned organohydrogel surface with water evaporating replenishment (POWER) for ultrawide time‐range biosensing, which integrated hydrophilic hydrogel domains and hydrophobic organogel background. The hydrogel domains on the surface can supply water to the pinned droplets through capillary channels formed in the nether organohydrogel bulk. The organogel background can inhibit water evaporation like the wax coating of leaves. Such a unique bioinspired design enables ultrawide time‐range biosensing in open environment from a few minutes to more than five hours involving a variety of analytes such as ions, small molecules, and macromolecules. The POWER provides a feasible and open biosensing platform for ultrawide time‐range reactions. [ABSTRACT FROM AUTHOR]

Nanoparticle aggregation for constructing functional materials has shown enormous advantages in various applications. Most efforts focused on ordered nanoparticle aggregation for specific functions but were often limited to irreversible aggregation processes due to the thermodynamic equilibrium. Herein, we report a reversible disordered aggregation of SiO2‐PNIPAAm nanoparticles (SPNPs) through thermo‐responsive jamming, obtaining smart liquid–solid switchable materials. The smart materials can display a switch between liquid‐like state and solid‐like state responding to a temperature change. This unique macroscopic behavior originates from the reversible disordered aggregation modulated by temperature‐dependent hydrophobic interactions among the SPNPs. Notably, the materials at the solid‐like state show anti‐impact properties and can withstand the impact of a steel sphere with a speed of 328 cm s−1. We envision that this finding offers inspiration to design smart liquid–solid switchable materials for impact protection. [ABSTRACT FROM AUTHOR]

Nanoparticle aggregation for constructing functional materials has shown enormous advantages in various applications. Most efforts focused on ordered nanoparticle aggregation for specific functions but were often limited to irreversible aggregation processes due to the thermodynamic equilibrium. Herein, we report a reversible disordered aggregation of SiO2‐PNIPAAm nanoparticles (SPNPs) through thermo‐responsive jamming, obtaining smart liquid–solid switchable materials. The smart materials can display a switch between liquid‐like state and solid‐like state responding to a temperature change. This unique macroscopic behavior originates from the reversible disordered aggregation modulated by temperature‐dependent hydrophobic interactions among the SPNPs. Notably, the materials at the solid‐like state show anti‐impact properties and can withstand the impact of a steel sphere with a speed of 328 cm s−1. We envision that this finding offers inspiration to design smart liquid–solid switchable materials for impact protection. [ABSTRACT FROM AUTHOR]

Surface adhesion has a great contradiction in high strength and good reversibility given their mutually exclusive requirements of fixed crosslinked networks and dynamic chain motion. Herein, we demonstrate a supramolecular organoplatinum(II) adhesive system regulated by intermolecular PtII⋅⋅⋅PtII interactions that can simultaneously achieve high‐strength and excellent reversible adhesion to various substrates. Upon alternating temperature, the assembly of suitably substituted organoplatinum(II) molecules can switch between well‐ordered and disordered states via tuning PtII⋅⋅⋅PtII interactions, resulting in stable reversible adhesion even after 100 cycles with a robust strength of ≈1.25 MPa and a large on‐off ratio of ≈25. Along with the switch of PtII⋅⋅⋅PtII contacts, the surface adhesion of organoplatinum(II) adhesives can be monitored by their changes in electrical signals. This study will open up new inspirations for developing high‐performance reversible adhesives. [ABSTRACT FROM AUTHOR]

Surface adhesion has a great contradiction in high strength and good reversibility given their mutually exclusive requirements of fixed crosslinked networks and dynamic chain motion. Herein, we demonstrate a supramolecular organoplatinum(II) adhesive system regulated by intermolecular PtII⋅⋅⋅PtII interactions that can simultaneously achieve high‐strength and excellent reversible adhesion to various substrates. Upon alternating temperature, the assembly of suitably substituted organoplatinum(II) molecules can switch between well‐ordered and disordered states via tuning PtII⋅⋅⋅PtII interactions, resulting in stable reversible adhesion even after 100 cycles with a robust strength of ≈1.25 MPa and a large on‐off ratio of ≈25. Along with the switch of PtII⋅⋅⋅PtII contacts, the surface adhesion of organoplatinum(II) adhesives can be monitored by their changes in electrical signals. This study will open up new inspirations for developing high‐performance reversible adhesives. [ABSTRACT FROM AUTHOR]

Excessive exudate secreted from diabetic wounds often results in skin overhydration, severe infections, and secondary damage upon dressing changes. However, conventional wound dressings are difficult to synchronously realize the non‐maceration of wound sites and rapid exudate transport due to their random porous structure. Herein, a self‐pumping Janus hydrogel with aligned channels (JHA) composed of hydrophilic poly (ethylene glycol) diacrylate (PEGDA) hydrogel layer and hydrophobic polyurethane (PU)/graphene oxide (GO)/polytetrafluoroethylene (PTFE) layer is designed to rapidly export exudate and accelerate diabetic wound healing. In the design, the ice‐templating process endows the hydrophilic hydrogel layer with superior liquid transport ability and mechanical strength due to the formation of aligned channel structure. The hydrophobic layer with controlled thickness functions as an effective barrier to prevent exudate from wetting the skin surface. Experiments in diabetic rat model show that JHA can significantly promote re‐epithelialization and collagen deposition, shorten the inflammation phase, and accelerate wound healing. This unique JHA dressing may have great potential for real‐life usage in clinical patients. [ABSTRACT FROM AUTHOR]

In nature, many organisms are able to accommodate a complex living environment by developing biological wet adhesive surfaces with unique functions such as fixation and predation. Significantly, most of these outstanding functions originate from the specialized micro/nanostructures and/or chemical components of these natural organisms. To design artificial surfaces with remarkable wet adhesive properties, the underlying mechanisms of the fascinating adhesion phenomena are further explored and summarized to provide continuous inspiration. Herein, a systematic overview of biological wet adhesive surfaces and the corresponding artificial counterparts from the perspective of surface micro/nanostructures is provided. First, the research progress of the typical biological wet adhesive surfaces such as the octopus, tree frogs, and mayfly larvae is introduced. Then, the fundamental models of surface adhesion in natural organisms and the commonly used instruments for measuring adhesion force are discussed. Later, the corresponding artificial wet adhesive surfaces inspired by these representative organisms are highlighted. After that, the typical methods for fabricating these surfaces are briefly introduced. Finally, future challenges and opportunities to develop bioinspired multiscaled wet adhesive surfaces with controlled adhesion are presented. [ABSTRACT FROM AUTHOR]