Despite the soft appearance of their feet, abalones can crawl quickly on sharp objects. Tests using rough substrates aligned with blades or posts found that the animal has two adaptations to guarantee its safety on these surfaces. Mechanical compression tests showed that the abalone foot muscle is inherently robust and can resist penetration by sharp objects. A finite element simulation indicated that to avoid being pierced, abalone controls the shape of its foot to wrap it around sharp objects, thereby greatly reducing the stress concentration. These analyses may aid the engineering of new materials and devices for fields including soft robotics and aircraft.

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constructing diverse TA coatings via the formation of supramolecular networks. [15] TA networks are formed based on various interactions, such as coordination with metal ions, [16,17] covalent reaction associated with oxidation, [18] hydrogen bonding interactions, [19,20] as well as hydrophobic and electrostatic interactions. [21,22] However, the formation of networks often relies on an inefficient TA deposition from the reaction solution to the substrate interface, where the reaction solution with a milligram per milliliter concentration only results in a microgram per square centimeter coated substrate, [23] making TA coating time-consuming, tedious, reagent wasting, and difficult to scale up. Therefore, developing a facile, efficient, and versatile polyphenol coating strategy and exploring its novel applications are urgently required.In amyloidosis, protein plaques, generated through the dynamic assembly and aggregation of activated amyloid-associated proteins, can be regarded as a dense coating deposited on animal tissue surfaces. [24,25] Additionally, host-guest interactions, through the structural match between two materials, offer the unique advantages of tunable dynamic assembly [26] and stimuli-responsive (redox, pH, and temperature), [27,28] due to the dynamic, reversible, and adaptive nature. [29,30] This may open up a promising yet underexplored platform for the construction of a new-style polyphenol coating.Inspired by the dynamic assembly of amyloid, we introduced a novel, facile and versatile coating strategy integrating the advantages of both polyphenol chemistry and host-guest chemistry using TA and polycyclodextrin (PCD) particles. Cyclodextrin (CD) is chosen as a host molecule owing to its excellent biocompatibility and multiple hydroxyl groups that are easy to be modified. [31] Due to the previously undeveloped relationship between CD and TA, we first screened optimal CD types and evaluated their interactions with TA by molecular dynamics (MD) simulations and isothermal titration calorimetry (ITC). Then, PCD was prepared via crosslinking of CD with epichlorohydrin, and further mixed with TA to form TA/ PCD particles (TPP). We found that TPP driven by host-guest interaction can dynamically assemble into a large and collective aggregation due to the competition between the self-propulsion of negatively charged particles and attractive interaction Developing a facile, efficient, and versatile polyphenol coating strategy and exploring its novel applications are of great significance in the fields of material surfaces and interfaces. Herein, a one-step assembly strategy for constructing novel tannic acid (TA) coatings via a solvent evaporation method is reported using TA and polycyclodextrin (PCD) particles (TPP). TPP with a high phenolic group activity of 88% integrates the advantages of host-guest and polyphenol chemistry. The former can drive TPP dynamically assemble into a large and collective aggregation activated by high temperature or density, and the latter provides excellent adhesion prope...

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