Dechao Hu

In pursuit of high‐performance flexible strain sensors, achieving an optimal trade‐off among linearity, sensitivity, and strain sensing range remains a critical challenge. Inspired by the wrinkled‐leaf viburnum, we develop a Janus sensor that replicates its asymmetric structure. It comprises a dense, micro‐wrinkled natural rubber (NR)/graphene (GRs) top layer and a loose NR/carbon nanotubes (CNTs) bottom layer, fabricated via facile layer‐by‐layer filtration and pre‐stretching strategy. This bio‐inspired design enables the sensor with a synergistic sensing mechanism: wrinkle‐guided microcrack ensures highly sensitive linear response at low strains; strain‐phase division maintains signal continuity at medium strains; and parallel conductive circuits provide robustness at high strains. As a result, the sensor achieves an exceptional combination of ultra‐high linearity (R ² > 0.999) and sensitivity (gauge factors, GF > 14) across 0–100% strain, with a wide sensing range (> 400%) and fast response (0.16 s). We demonstrate its practical value in human motion detection, physiological signal monitoring, and an intelligent glove system for gesture recognition and human‐machine interaction, highlighting its promising potential for advanced wearable devices and human‐machine interactive systems.

Tissue adhesives are increasingly sought after for their potential to minimize invasiveness, simplify surgical procedures, and reduce operative times; however, conventional polyacrylamide (PAM)-based hydrogels are often hindered by irreversible bonding, which limits their reusability and compromises both mechanical integrity and self-healing ability. Motivated by the natural adhesion mechanisms of mussels, we have developed an innovative tissue adhesive hydrogel by incorporating polydopamine (PDA) and cysteine (Cys) into a PAM matrix via free radical polymerization, with polyethylene glycol diacrylate (PEGDA) serving as an effective cross-linker. In our system, PDA contributes essential catechol groups for strong tissue adhesion, while Cys not only preserves these groups from oxidation but also enhances hydrophilic interactions, resulting in a PDA-Cys-PAM hydrogel with a tensile strength of 23.4-30.7 kPa, a fracture elongation of 628-706%, and an elongation recovery of 48%. Significantly, the seamless integration of nanoclay into the hydrogel network further reinforces its structure and improves energy dissipation, leading to a marked enhancement of the self-healing performance─evidenced by an increase in the elongation recovery rate to 71.9%─without compromising the inherent mechanical properties. Moreover, in vitro assays with NIH3T3 cells demonstrate excellent biocompatibility, underscoring the potential of this synergistic design. Overall, our work not only elucidates the distinct and cooperative roles of PDA, Cys, and nanoclay but also represents a significant advancement in the design of reusable, high-performance tissue adhesives for potential applications in tissue repair and regeneration.