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Amphibian adhesion systems can enhance adhesion forces on wet or rough surfaces via hexagonal architectures, enabling omnidirectional peel resistance and drainage against wet and rough surfaces, often under flowing water. In addition, an octopus has versatile suction cups with convex cup structures located inside the suction chambers for strong adhesion in various dry and wet conditions. Highly air-permeable, water-drainable, and reusable skin patches with enhanced pulling adhesion and omnidirectional peel resistance, inspired by the microchannel network in the toe pads of tree frogs and convex cups in the suckers of octopi, are presented. By investigating various geometric parameters of microchannels on the adhesive surface, a simple model to maximize peeling strength via a time-dependent zig-zag profile and an arresting effect against crack propagation is first developed. Octopus-like convex cups are employed on the top surfaces of the hexagonal structures to improve adhesion on skin in sweaty and even flowing water conditions. The amount of reduced graphene oxide nanoplatelets coated on the frog and octopus-inspired hierarchical architectures is controlled to utilize the patches as flexible electrodes which can monitor electrocardiography signals without delamination from wet skin under motion.

High adhesion and water resistance on skin surfaces are highly demanded properties for wearable and skin‐attachable electronics in various medical applications. Here, stretchable electronics with octopus‐like patterns (OPs) imprinted on a carbon‐based conductive polymer composite (CPC) film are presented. The bioinspired conductive suckers with dome‐like architectures are successfully exploited to sustain weight (500 g) in underwater, wherein this performance is known to be challenging. In addition, the artificial patch allows highly adhesive capabilities under both dry and wet conditions on various surfaces such as silicon (max. 5.24 N cm−2) and skin replica (max. 1.89 N cm−2) without contamination after detachment with an effortless peel‐off technique. The resulting device with low volumetric ratio of conductive carbon black presents sensitive and reliable piezoresistive responses to lateral strain and vertical pressure. By controlling the ratio of the carbon nanoplatelets in the polymeric matrix, electronic patch demonstrates both detection of electrocardiogram (ECG) and bending motions of wrist in dry and wet environments. Based on the characteristics shown in this work, the proposed electronic patch is a promising approach to realize wearable and skin‐attachable sensor devices for in vitro and in vivo monitoring of various biosignals.

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