Stress-enhanced gelation: a dynamic nonlinearity of elasticity.
Stress-enhanced gelation: a dynamic nonlinearity of elasticity.
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DOI：
10.1103/physrevlett.110.018103
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发表时间：
2013-01-04
影响因子：
8.6
通讯作者：
Weitz DA
中科院分区：
文献类型：
--
作者：
Yao NY;Broedersz CP;Depken M;Becker DJ;Pollak MR;Mackintosh FC;Weitz DA
生物聚合物网络的一个标志是它们对压力的敏感性，这反映在明显的非线性弹性硬化上。在这里，我们展示了由α-肌动蛋白-4交联的F-肌动蛋白组成的生物聚合物网络中明显的动态非线性。施加的应力延迟了松弛和流动的开始，显著地增强了凝胶化，并将类固体行为的区域扩展到低得多的频率。我们表明，这种宏观网络响应可以在单分子水平上解释为交联剂在负载下结合亲和力的增加，这是一种捕获键行为的特征。
A hallmark of biopolymer networks is their sensitivity to stress, reflected by pronounced nonlinear elastic stiffening. Here, we demonstrate a distinct dynamical nonlinearity in biopolymer networks consisting of F-actin cross-linked by α-actinin-4. Applied stress delays the onset of relaxation and flow, markedly enhancing gelation and extending the regime of solid-like behavior to much lower frequencies. We show that this macroscopic network response can be accounted for at the single molecule level by the increased binding affinity of the cross-linker under load, characteristic of catch-bond-like behavior.