Muscle-like fatigue-resistant hydrogels by mechanical training
Muscle-like fatigue-resistant hydrogels by mechanical training
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DOI：
10.1073/pnas.1903019116
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发表时间：
2019-05-21
影响因子：
11.1
通讯作者：
Zhao, Xuanhe
中科院分区：
文献类型：
--
作者：
Lin, Shaoting;Liu, Ji;Zhao, Xuanhe
骨骼肌具有高抗疲劳性（1，000 J/m2）、高强度（1 MPa）、低杨氏模量（100 kPa）和高含水量（70至80wt%）的组合性质，这在合成水凝胶中还没有实现。肌肉样性质对于水凝胶在承重人造组织和软装置中的新生应用是非常期望的。在这里，我们提出了一种策略的机械训练，以实现对齐的纳米纤维结构的骨骼肌合成水凝胶，从而在组合肌肉样的属性。这些特性是通过训练诱导的纳米原纤维排列获得的，而无需额外的化学修饰或添加剂。水凝胶的断裂过程的原位共聚焦显微镜显示，抗疲劳性是由对齐的纳米原纤维的裂纹钉扎引起的，其需要比相应的无定形聚合物链高得多的能量来断裂。这种策略特别适用于水凝胶的3D打印微结构，在其中我们可以实现各向同性的抗疲劳性，坚固而柔顺的特性。
Skeletal muscles possess the combinational properties of high fatigue resistance (1,000 J/m(2)), high strength (1 MPa), low Young's modulus (100 kPa), and high water content (70 to 80 wt %), which have not been achieved in synthetic hydrogels. The muscle-like properties are highly desirable for hydrogels' nascent applications in load-bearing artificial tissues and soft devices. Here, we propose a strategy of mechanical training to achieve the aligned nanofibrillar architectures of skeletal muscles in synthetic hydrogels, resulting in the combinational muscle-like properties. These properties are obtained through the training-induced alignment of nanofibrils, without additional chemical modifications or additives. In situ confocal microscopy of the hydrogels' fracturing processes reveals that the fatigue resistance results from the crack pinning by the aligned nanofibrils, which require much higher energy to fracture than the corresponding amorphous polymer chains. This strategy is particularly applicable for 3D-printed microstructures of hydrogels, in which we can achieve isotropically fatigue-resistant, strong yet compliant properties.