Abstract：
Bacterial cellulose (BC) with its inherent nanofibrils framework is an attractive building block for the fabrication of sustainable bioelectronics, but there still lacks an effective and green strategy to regulate the hydrogen-bonding topological structure of BC to improve its optical transparency and mechanical stretchability. Herein, we report an ultra-fine nanofibril-reinforced composite hydrogel by utilizing gelatin and glycerol as hydrogen-bonding donor/acceptor to mediate the rearrangement of the hydrogen-bonding topological structure of BC. Attributing to the hydrogen-bonding structural transition, the ultra-fine nanofibrils were extracted from the original BC nanofibrils, which reduced the light scattering and endowed the hydrogel with high transparency. Meanwhile, the extracted nanofibrils were connected with gelatin and glycerol to establish an effective energy dissipation network, leading to an increase in stretchability and toughness of hydrogels. The hydrogel also displayed tissue-adhesiveness and long-lasting water-retaining capacity, which acted as bio-electronic skin to stably acquire the electrophysiological signals and external stimuli even after the hydrogel was exposing to air condition for 30 days. Moreover, the transparent hydrogel could also serve as a smart skin dressing for optical identification of bacterial infection and on-demand antibacterial therapy after combined with phenol red and indocyanine green. This work offers a strategy to regulate the hierarchical structure of natural materials for designing skin-like bioelectronics toward green, low cost, and sustainability.
摘要：
细菌纤维素（BC）具有其固有的纳米原纤维框架是制造可持续生物电子学的一个有吸引力的构建块，但是仍然缺乏有效的绿色策略来调节BC的氢键拓扑结构，以提高其光学透明度和机械拉伸性。在这里，我们报道了一种超细纳米原纤维增强的复合水凝胶，它利用明胶和甘油作为氢键供体/受体来介导BC的氢键拓扑结构的重排。归因于氢键结构转变，超细纳米原纤维是从原始的BC纳米原纤维中提取出来的，这减少了光散射并赋予水凝胶高透明度。同时,提取的纳米原纤维与明胶和甘油连接，建立有效的能量耗散网络，导致水凝胶的拉伸性和韧性增加。水凝胶还显示出组织粘附性和持久的保水能力，即使在水凝胶暴露于空气条件下30天后，其也充当生物电子皮肤以稳定地获取电生理信号和外部刺激。此外，透明水凝胶还可以用作智能皮肤敷料，用于光学识别细菌感染和与酚红和吲哚菁绿结合后的按需抗菌治疗。这项工作提供了一种策略来调节天然材料的层次结构，以设计皮肤状生物电子学向绿色，低成本,和可持续性。
