Functional integration is an inherent characteristic for multiscale structures of biological materials. In this contribution, we first investigate the liquid-solid adhesive forces between water droplets and superhydrophobic gecko feet using a high-sensitivity micro-electromechanical balance system. It was found, in addition to the well-known solid-solid adhesion, the gecko foot, with a multiscale structure, possesses both superhydrophobic functionality and a high adhesive force towards water. The origin of the high adhesive forces of gecko feet to water could be attributed to the high density nanopillars that contact the water. Inspired by this, polyimide films with gecko-like multiscale structures were constructed by using anodic aluminum oxide templates, exhibiting superhydrophobicity and a strong adhesive force towards water. The static water contact angle is larger than 150° and the adhesive force to water is about 66 μN. The resultant gecko-inspired polyimide film can be used as a "mechanical hand" to snatch micro-liter liquids. We expect this work will provide the inspiration to reveal the mechanism of the high-adhesive superhydrophobic of geckos and extend the practical applications of polyimide materials.

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Ceramic/polymer composite equipped with 3D interlocking skeleton (3D IL) is developed through a simple freeze-casting method, exhibiting exceptionally light weight, high strength, toughness, and shock resistance. Long-range crack energy dissipation enabled by 3D interlocking structure is considered as the primary reinforcing mechanism for such superior properties. The smart composite design strategy should hold a place in developing future structural engineering materials.

Particulate matter (PM) pollution is a serious threat to human health. Zeolitic imidazolate framework-8 (ZIF-8) is a kind of metal-organic framework, and ZIF-8 not only can capture PM 2.5 efficiently but also possesses excellent chemical and thermal stability. In this study, ZIF-8-modified soluble polyimide (PI) nanofibrous membranes were prepared via an electrospinning process. As a result, the PI-ZIF membrane shows high PM 2.5 filtration efficiency (up to 96.6 ± 2.9%), superior thermal stability (up to 300 °C), good transmittance, excellent mechanical properties, and low pressure drop. The prepared PI-ZIF membrane with excellent comprehensive property shows a promising application in PM 2.5 capture, especially in harsh conditions.

A biomimetic “cactus spine” with hierarchical groove structure is designed and fabricated using simple electrospinning. This novel artificial cactus spine possesses excellent fog collection and water transportation ability. A model cactus equipped with artificial spines also shows a great water storage capacity. The results can be helpful in the development of water collectors and may make a contribution to the world water crisis.

The brick–mortar structure CuS/PVDF nanocomposite films with enhanced absorption properties were fabricated based on the selectively synthesized CuS hexagonal nanoplatelets and PVDF.

One of the biggest problems of heart failure is the heart's inability to effectively pump blood to meet the body's demands, which may be caused by disease-induced alterations in contraction properties (such as contractile force and Young's modulus). Thus, it is very important to measure contractile properties at single cardiac myocyte level that can lay the foundation for quantitatively understanding the mechanism of heart failure and understanding molecular alterations in diseased heart cells. In this article, we report a novel single cardiac myocyte contractile force measurement technique based on moving a magnetic bead. The measuring system is mainly composed of 1), a high-power inverted microscope with video output and edge detection; and 2), a moving magnetic bead based magnetic force loading module. The main measurement procedures are as follows: 1), record maximal displacement of single cardiac myocyte during contraction; 2), attach a magnetic bead on one end of the myocyte that will move with myocyte during the contraction; 3), repeat step 1 and record contraction processes under different magnitudes of magnetic force loading by adjusting the magnetic field applied on the magnetic bead; and 4), derive the myocyte contractile force base on the maximal displacement of cell contraction and magnetic loading force. The major advantages of this unique approach are: 1), measuring the force without direct connections to the cell specimen (i.e., "remote sensing", a noninvasive/minimally invasive approach); 2), high sensitivity and large dynamic range (force measurement range: from pico Newton to micro Newton); 3), a convenient and cost-effective approach; and 4), more importantly, it can be used to study the contractile properties of heart cells under different levels of external loading forces by adjusting the magnitude of applied magnetic field, which is very important for studying disease induced alterations in contraction properties. Experimental results demonstrated the feasibility of proposed approach.

Superhydrophobic surface with high solid/liquid adhesion is of great fundamental and technological importance. However, the fabrication of adhesive superhydrophobic polymer surfaces with high stability is rare, which limits the utilization of such surfaces in harsh environments. This paper illustrates a simple electrospinning way to produce fluorinated polyimide nanofibric mat with adhesive superhydrophobicity as well as high thermal stability. The water contact angle on the mat reaches as high as 157.8 and the adhesive force to a water drop is up to 98.3 mN. Moreover, the adhesive superhydrophobic polyimide mat is able to stand extreme heat up to 300 C. By virtue of the facile electrospinning technique, large-area flexible mats can be easily achieved. Such an electrospun fluorinated polyimide mat will possess broader applications than ordinary organic superhydrophobic surfaces owing to its excellent stability in harsh environments.