Ludwanowski Simon, Skarsetz Oliver, Creusen Guido, Hoenders Daniel, Straub Paula, Walther Andreas
A3BMS Lab-Active, Adaptive and Autonomous Bioinspired Materials, Institute for Macromolecular Chemistry, University of Freiburg, Stefan-Meier-Straße 31, 79104, Freiburg, Germany.
Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Straße 21, 79104, Freiburg, Germany.
Angew Chem Int Ed Engl. 2021 Feb 19;60(8):4358-4367. doi: 10.1002/anie.202011592. Epub 2020 Dec 21.
Responsive materials, such as switchable hydrogels, have been largely engineered for maximum changes between two states. In contrast, adaptive systems target distinct functional plateaus between these maxima. Here, we demonstrate how the photostationary state (PSS) of an E/Z-arylazopyrazole photoswitch can be tuned by the incident wavelength across a wide color spectrum, and how this behavior can be exploited to engineer the photo-dynamic mechanical properties of hydrogels based on multivalent photoswitchable interactions. We show that these hydrogels adapt to the wavelength-dependent PSS and the number of arylazopyrazole units by programmable relationships. Hence, our material design enables the facile adjustment of the mechanical properties without laborious synthetic efforts. The concept goes beyond the classical switching from state A to B, and demonstrates pathways for a truly wavelength-gated adaptation of hydrogel properties potentially useful to engineer cell fate or in soft robotics.
响应性材料，如可切换水凝胶，在很大程度上已被设计用于实现两种状态之间的最大变化。相比之下，自适应系统的目标是在这些最大值之间实现不同的功能平稳状态。在此，我们展示了E/Z-芳基偶氮吡唑光开关的光稳态（PSS）如何通过宽光谱范围内的入射波长进行调节，以及如何利用这种行为基于多价光开关相互作用来设计水凝胶的光动力机械性能。我们表明，这些水凝胶通过可编程关系适应波长依赖性PSS和芳基偶氮吡唑单元的数量。因此，我们的材料设计能够轻松调整机械性能，而无需进行费力的合成工作。这一概念超越了从状态A到B的经典切换，并展示了水凝胶性能真正实现波长门控适应的途径，这可能对细胞命运工程或软机器人技术有用。
