Department of Physics, University of Wisconsin-Milwaukee, 3135 N. Maryland Avenue, Milwaukee, Wisconsin 53211, United States.
J Phys Chem Lett. 2022 Aug 11;13(31):7139-7146. doi: 10.1021/acs.jpclett.2c01720. Epub 2022 Jul 28.
Both synthetic and natural protein-based materials are made of randomly oriented cross-linked molecules. Here we introduce a coarse-grained approach to estimate the average force-per-molecule for materials made from globular proteins. Our approach has three steps: placement of molecules inside a unit volume, cross-linking, and trimming to remove the protein domains that do not participate to the force response. Following this procedure, we estimate the number of active domains per cross-section area, that allows for a direct calculation of the force-per-domain. Among the variables considered, we found that concentration was the most sensitive parameter. We then synthesized protein hydrogels made from BSA and polyprotein L and measured the stresses that these materials can withstand. We found that forces-per-molecules of up to 17 pN per domain can be obtained experimentally using protein hydrogels. Our approach represents an important step toward understanding the scaling of tension in biomaterials.
合成和天然蛋白基材料均由无规取向的交联分子组成。在这里，我们引入了一种粗粒化方法来估算由球状蛋白制成的材料的平均分子力。我们的方法分为三个步骤：分子在单位体积内的放置、交联和修剪以去除不参与力响应的蛋白质结构域。通过此过程，我们估算了每个横截面积的活性结构域数量，从而可以直接计算结构域力。在所考虑的变量中，我们发现浓度是最敏感的参数。然后，我们合成了由 BSA 和多蛋白 L 制成的蛋白质水凝胶，并测量了这些材料能够承受的应力。我们发现，使用蛋白质水凝胶可以在实验中获得高达每结构域 17 pN 的分子力。我们的方法代表了朝着理解生物材料张力缩放迈出的重要一步。
