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Although penguins live in the world’s coldest environment, frost and ice are seldom found on their feathers. That is to say, their feathers exhibit excellent antifrosting or anti-icing properties. We found that their air-infused microscale and nanoscale hierarchical rough structures endow the body feathers of penguins Spheniscus humboldti with hydrophobicity (water CA ≈ 147°) and antiadhesion characteristics (water adhesive force ≈ 23.4 μN), even for supercooled water microdroplets. A polyimide nanofiber membrane with novel microstructures was prepared on an asymmetric electrode by electrospinning, acting as an artificial replica of a penguin’s body feather. The unique microstructure of the polyimide nanofiber membrane results in a density gradient of the surface chemical substance, which is crucial to the formation of gradient changes of the contact angle and adhesive force. With decrease of the density of the surface chemical substance (i.e., with increase of the distance between adjacent fibers), the s...

The water strider is a wonderful case that we can learn from nature to understand how to stride on the water surface. Inspired by the unique hierarchical micro/nanostructure of the water strider leg, in this article, we designed and fabricated an artificial strider leg with refined nanogroove structure by using an electrospinning and sacrificial template method. A model water strider that was equipped with four artificial legs showed remarkable water-repellent performance; namely, it could carry a load that was about 7 times heavier than its own weight. Characterization demonstrated that, even though the artificial leg did not possess a superhydrophobic surface, the numerous nanogrooves could still provide a huge supporting force for the man-made model strider. This work enlightens the development of artificial water-walking devices for exploring and monitoring the surface of water. Because of the advances of the applied materials, the devices may fulfill tasks in a harsh aquatic environment.

A strategy to manipulate the disulfide bond breaking triggered unfolding, and subsequently assembly of human serum albumin (HSA) in a lipophilic drug-dependent manner is present. In this study, the hydrophobic region, a molecular switch of the HSA, was regulated to form HSA-paclitaxel (HSA-PTX) nanoparticles by a facile route. High-resolution transmission electron microscopy and fluorescence quenching indicate that HSA coassembled with PTX, which acts as a bridge to form core-shell nanoparticles about 50-240 nm in size, and that PTX might bind to the subdomain IIA sites of HSA. Change of ultraviolet absorption and circular dichroism spectra reveal the formation of HSA-PTX nanoparticles, which is a safety, injectable pharmaceutic nanocarrier system for tumor target. This method to prepare nanocarrier systems for hydrophobic guest molecules reveals a general principle of self-assembly for other plasma proteins and other pharmacologically active substances with poor water solubility. It also provides a basis for developing nanocarrier systems for a wide range of applications in nanomedicine, from drug delivery to bioimaging systems.