Wu Baoyi, Si Muqing, Hua Luqin, Zhang Dong, Li Wanning, Zhao Chuanzhuang, Lu Wei, Chen Tao
Laboratory of Advanced Marine Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
School of Chemical Sciences, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.
Adv Mater. 2024 Jun;36(25):e2401659. doi: 10.1002/adma.202401659. Epub 2024 Apr 3.
Cephalopods evolve the acetylcholine-gated actuation control function of their skin muscles, which enables their dynamic/static multimode display capacities for achieving perfectly spatial control over the colors/patterns on every inch of skin. Reproduction of artificial analogs that exhibit similar multimodal display is essential to reach advanced information three-dimensional (3D) encoding with higher security than the classic 2D-encoding strategy, but remains underdeveloped. The core difficulty is how to replicate such chemical-gated actuation control function into artificial soft actuating systems. Herein, this work proposes to develop azobenzene-functionalized poly(acrylamide) (PAAm) hydrogel systems, whose upper critical solution temperature (UCST) type actuation responsiveness can be intelligently programmed or even gated by the addition of hydrophilic α-cyclodextrin (α-CD) molecules for reversible association with pendant azobenzene moieties via supramolecular host-guest interactions. By employing such α-CD-gated hydrogel actuator as an analogue of cephalopods' skin muscle, biomimetic mechanically modulated multicolor fluorescent display systems are designed, which demonstrate a conceptually new α-CD-gated "thermal stimulation-hydrogel actuation-fluorescence output" display mechanism. Consequently, high-security 3D-encoding information carriers with an unprecedented combination of single-input multiple-output, dynamic/static dual-mode and spatially controlled display capacities are achieved. This bioinspired strategy brings functional-integrated features for artificial display systems and opens previously unidentified avenues for information security.
头足类动物进化出了其皮肤肌肉的乙酰胆碱门控驱动控制功能，这使其具备动态/静态多模式显示能力，能够对每一寸皮肤上的颜色/图案实现完美的空间控制。复制具有类似多模式显示的人工类似物对于实现比经典二维编码策略更高安全性的先进信息三维（3D）编码至关重要，但目前仍未得到充分发展。核心难题在于如何将这种化学门控驱动控制功能复制到人工软驱动系统中。在此，这项工作提出开发偶氮苯功能化的聚（丙烯酰胺）（PAAm）水凝胶系统，其临界溶解温度上限（UCST）型驱动响应性可以通过添加亲水性α-环糊精（α-CD）分子进行智能编程甚至门控，α-CD分子通过超分子主客体相互作用与侧链偶氮苯基团可逆缔合。通过将这种α-CD门控水凝胶致动器用作头足类动物皮肤肌肉的类似物，设计了仿生机械调制多色荧光显示系统，该系统展示了一种概念上新的α-CD门控“热刺激-水凝胶驱动-荧光输出”显示机制。因此，实现了具有单输入多输出、动态/静态双模式和空间控制显示能力的前所未有的组合的高安全性3D编码信息载体。这种受生物启发的策略为人工显示系统带来了功能集成特性，并为信息安全开辟了以前未被发现的途径。
