Conductive hydrogel-based epidermal sensors are attracting significant interest due to their great potential in soft robotics, electronic skins, bioelectronics and personalized healthcare monitoring. However, the conventional conductive hydrogel-based epidermal sensors cannot be degraded, resulting in the significant problem of waste, which will gradually increase the burden on the environment. Herein, degradable adhesive epidermal sensors were assembled using conductive nanocomposite hydrogels, which were prepared via the conformal coating of cellulose nanofiber (CNF) networks and supramolecular interaction among CNF, polydopamine (PDA), Fe³⁺, and polyacrylamide (PAM). They exhibited superior mechanical properties, reliable degradability (30 days in water), and excellent self-adhesiveness. The obtained hydrogels could be assembled as self-adhesive, degradable epidermal sensors for real-time human motion monitoring. Air could be sucked into the hydrogels during their swelling process, thereby oxidizing the tris-catechol–Fe³⁺ complexes and releasing Fe³⁺. Finally, the polymer networks were degraded via a Fenton-like reaction dominated by S₂O₈²⁻ and Fe(II/III) with the help of the catechol groups of PDA. This work paves the way for the potential fabrication of degradable, and self-adhesive epidermal sensors for applications in human–machine interactions, implantable bioelectronics, and personalized healthcare monitoring.

中文翻译：

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由导电纳米复合水凝胶制备的可降解自粘表皮传感器。

基于导电水凝胶的表皮传感器因其在软机器人，电子皮肤，生物电子学和个性化医疗保健监控方面的巨大潜力而​​受到广泛关注。然而，常规的基于导电水凝胶的表皮传感器不能被降解，从而导致严重的浪费问题，这将逐渐增加对环境的负担。本文中，使用导电纳米复合水凝胶组装可降解的粘合表皮传感器，该凝胶是通过纤维素纳米纤维（CNF）网络的保形涂层以及CNF，聚多巴胺（PDA），Fe ³⁺之间的超分子相互作用制备的和聚丙烯酰胺（PAM）。它们表现出优异的机械性能，可靠的可降解性（在水中浸泡30天）和出色的自粘性。所获得的水凝胶可以组装为自粘性，可降解的表皮传感器，用于实时人体运动监测。空气在其膨胀过程中可能被吸入水凝胶，从而氧化了tris-儿茶酚-Fe ³⁺复合物并释放出Fe ³⁺。最终，聚合物网络通过以S ₂ O ₈ ^2-和Fe（II / III）在PDA的邻苯二酚组的帮助下。这项工作为可降解的，可自粘的表皮传感器的潜在制造铺平了道路，这些传感器可用于人机交互，可植入生物电子学和个性化医疗保健监控。