Zhu Zhenghua, Ling Shengjie, Yeo Jingjie, Zhao Siwei, Tozzi Lorenzo, Buehler Markus J, Omenetto Fiorenzo, Li Chunmei, Kaplan David L
Department of Applied Engineering, Zhejiang Institute of Economic and Trade, Hangzhou, Zhejiang Province, 310018, China; Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA.
Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA; School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China.
Adv Funct Mater. 2018 Mar 7;28(10). doi: 10.1002/adfm.201704757. Epub 2018 Jan 8.
Hydrogels have been the focus of extensive research due to their potential use in fields including biomedical, pharmaceutical, biosensors, and cosmetics. However, the general weak mechanical properties of hydrogels limit their utility. Here, we generate pristine silk fibroin (SF) hydrogels with excellent mechanical properties via a binary solvent induced conformation transition (BSICT) strategy. In this method, the conformational transition of SF is regulated by moderate binary solvent diffusion and SF/solvent interactions. β-sheet formation serves as the physical crosslinks that connect disparate protein chains to form continuous 3D hydrogel networks, avoiding complex chemical and/or physical treatments. The Young's modulus of these new BSICT-silk fibroin hydrogels can reach up to 6.5±0.2 MPa, tens to hundreds of times higher than that of conventional hydrogels (0.01-0.1 MPa). These new materials filled the "empty soft materials space" in the elastic modulus/strain Ashby plot. More remarkably, the BSICT-SF hydrogels can be processed into different constructions through different polymer and/or metal based processing techniques, such as molding, laser cutting, and machining. Thus, these new hydrogel systems exhibit potential utility in many biomedical and engineering fields.
水凝胶因其在生物医学、制药、生物传感器和化妆品等领域的潜在应用而成为广泛研究的焦点。然而，水凝胶普遍较弱的机械性能限制了它们的实用性。在此，我们通过二元溶剂诱导构象转变（BSICT）策略制备了具有优异机械性能的纯丝素蛋白（SF）水凝胶。在该方法中，SF的构象转变由适度的二元溶剂扩散和SF/溶剂相互作用调控。β-折叠的形成作为物理交联，连接不同的蛋白质链以形成连续的三维水凝胶网络，避免了复杂的化学和/或物理处理。这些新型BSICT-丝素蛋白水凝胶的杨氏模量可达6.5±0.2 MPa，比传统水凝胶（0.01-0.1 MPa）高几十到几百倍。这些新材料填补了弹性模量/应变阿什比图中的“软材料空白区域”。更值得注意的是，BSICT-SF水凝胶可通过不同的基于聚合物和/或金属的加工技术，如模塑、激光切割和机械加工，加工成不同的结构。因此，这些新型水凝胶体系在许多生物医学和工程领域展现出潜在的应用价值。
