The human quest for beauty is manifested in numerous body decoration fashions such as makeups, tattoos, and stickers. The ancient “kirigami” art offers a variety of choices for sticker‐type body beautification, whereby with simple cutting, complex networks potential use as microfluidic channels and stretchable materials can be fabricated. Inspired by the fish‐scale pattern and kirigami art, a fish‐like wearable biosensor is designed and fabricated. This highly stretchable, well‐aerated, disposable, and wearable fish sticker enables sweat collection, diagnostics, and motion monitoring. A structure of photonic crystals is integrated in the paper channels for fluorescence enhancement sensing of sweat lactic acid and urea, and a stretchable electronic paper network induced sensitive resistance changes during the movement. The sensor is amenable to a variety of applications, such as personal care and human–machine interaction. The combination of art and sensing also provides a pleasant‐looking solution for both health and beauty.

The rapid development of a self-powered system (SPS) has aroused an increasing interest in the field of wearable electronics. The current development trend in wearable electronics is toward integration, portability, miniaturization, and sustainability. Hence, a wearable piezoelectric-driven self-powered patterned electrochromic supercapacitor (ESC) is presented here, which is integrated with the energy harvesting, conversion, storage and indication technologies. The patterned polyaniline (PANI) electrodes electrodeposited by coupling cyclic voltammetric and galvanostatic (CV-GS) techniques were assembled as patterned ESC, which served to store the energy and indicate the charging/discharging status simultaneously. With the advantages of flexibility and biocompatibility, the polyvinylidene difluoride (PVDF) nanofibers were fabricated by electrospinning to establish the piezoelectric nanogenerators (PENGs) as the energy-harvesting device, which can be attached to human body to harvest mechanical kinetic energy. The integrated wearable self-powered system (SPS) can harvest human motion energy and other mechanical energy, then transfer the mechanical energy to electric energy by a rectifier for charging ESC, which provides a sustainable energy supply for wearable electronics. It is foreseen that the self-powered patterned ESC that we proposed will have a broad application in the fields of flexible artificial skin, smart robots, artificial intelligence, and implantable or portable medical devices.

As an enabling technique, microfluidic systems have developed rapidly in recent years to emerge as a powerful tool in the field of biomedical engineering. Microfluidics enables miniaturized, integratable, high‐throughput and automated biochemical analysis, fabrication of biomaterials with precisely controlled structures and compositions, and construction of organ‐on‐a‐chip systems with specific organ features and functions. Recent advances in microfluidics for biomedical engineering applications are outlined in this review, emphasizing the basic concepts and research trends in this field. The review covers recent research in microfluidics for bioassays, biofabrication, and tissue engineering. The technologies involved in these applications are highlighted, such as those for fabricating sensitive and portable bioassays, for fabricating biomaterials in a regulated manner, and for fabricating 3D cell culture scaffolds and microenvironments.

of liquid droplets, generation of micropattern, and liquid enrichment. [5] To fabricate such surfaces, traditional methods mainly focus on the combination of capillary structures or hydrophilic/oleophilic patterns with (super)hydrophobic/(super) oleophobic surfaces. Kong and Wang's group developed a mechano regulated surface for manipulating liquid droplets. [6] Their surface consists of a background mesh and a movable microfiber array with contrastive wettability. Song's group, [7] Levkin's group, [8] and Wang's group [9] have done much work in 2D droplet microarrays for biological applications by using discontinuous dewetting. However, these methods are highly dependent on the chemical modification and therefore most of the as-prepared samples could not be applied to various liquids. Meanwhile, these methods usually failed to tune the adhesion behavior toward micro or macro droplets. [10] In the past decade, springtails have aroused much attention because their skins are able to repel water as well as oils with relatively low surface energy. [11] This is one extreme example that the repellency does not rely on fluorinated compounds but micro/nano negative overhangs. Similar structures can effectively suspend liquid to form a Cassie state. [12] Based on the springtail-skin inspired multiply re-entrant structures, various surfaces have been developed to achieve liquid antiadhesion, [13] airtrapping, [14] slippery states, [15] and so on. [16] Meanwhile, Hensel's, Gorb's, and Pang's groups have revealed that re-entrant structures represent a proven strategy to improve the dry adhesion strength, which makes them potential usage in walking robots and grippers. [17] However, theories and experimental results about their influence on liquid adhesion are still rare. If the liquid adhesion can be tuned on multiply re-entrant structures, the above-mentioned limitations can all be overcome due to their advantages of universal and modificationindependent antipenetration ability.In this work, inspired by the springtail skin and the gecko feet at adhered state, we demonstrate that programmable liquid adhesion was realized on the 3D-printed micro doubly re-entrant arrays. On one hand, the two-photon polymerization (TPP)-based 3D printing technology allows the fabrication of the micro re-entrant structures with high resolution. On the other hand, the arrangement of the arrays can be readily Surfaces combining antispreading and high adhesion can find wide applications in the manipulation of liquid droplets, generation of micropatterns and liquid enrichment. To fabricate such surfaces, almost all the traditional methods demand multi-step processes and chemical modification. And even so, most of them cannot be applied for some liquids with extremely low surface energy. In the past decade, multiply re-entrant structures have aroused much attention because of their universal and modification-independent antiadhesion or antipenetration ability. Unfortunately, theories and applications about their liquid adhesion behavior are stil...

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