Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093, USA.
Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, Amsterdam 1098XH, Netherlands.
Sci Adv. 2023 Oct 20;9(42):eadi8643. doi: 10.1126/sciadv.adi8643.
Mechanosensing, the transduction of extracellular mechanical stimuli into intracellular biochemical signals, is a fundamental property of living cells. However, endowing synthetic materials with mechanosensing capabilities comparable to biological levels is challenging. Here, we developed ultrasensitive and robust mechanoluminescent living composites using hydrogels embedded with dinoflagellates, unicellular microalgae with a near-instantaneous and ultrasensitive bioluminescent response to mechanical stress. Not only did embedded dinoflagellates retain their intrinsic mechanoluminescence, but with hydrophobic coatings, living composites had a lifetime of ~5 months under harsh conditions with minimal maintenance. We 3D-printed living composites into large-scale mechanoluminescent structures with high spatial resolution, and we also enhanced their mechanical properties with double-network hydrogels. We propose a counterpart mathematical model that captured experimental mechanoluminescent observations to predict mechanoluminescence based on deformation and applied stress. We also demonstrated the use of the mechanosensing composites for biomimetic soft actuators that emitted colored light upon magnetic actuation. These mechanosensing composites have substantial potential in biohybrid sensors and robotics.
机械感知，即将细胞外的机械刺激转化为细胞内的生化信号，是活细胞的基本特性。然而，赋予合成材料与生物水平相当的机械感知能力是具有挑战性的。在这里，我们使用含有甲藻的水凝胶开发了超灵敏和稳健的机械发光活体复合材料，甲藻是一种单细胞微藻，对机械应力具有近乎即时和超灵敏的生物发光响应。嵌入的甲藻不仅保留了其内在的机械发光特性，而且经过疏水涂层处理后，在恶劣条件下的寿命约为 5 个月，几乎无需维护。我们使用 3D 打印技术将活体复合材料制成具有高空间分辨率的大型机械发光结构，并使用双网络水凝胶进一步增强其机械性能。我们提出了一个对应的数学模型，该模型捕捉了实验机械发光观察结果，以根据变形和施加的应力来预测机械发光。我们还展示了使用机械感知复合材料作为仿生软致动器的应用，这些软致动器在磁场作用下会发出彩色光。这些机械感知复合材料在生物混合传感器和机器人技术方面具有巨大的潜力。
