Kryuchkova Anastasia, Mikhailova Mariia, Zelenovskii Pavel, Bdikin Igor, Kholkin Andrei, Krivoshapkina Elena F, Krivoshapkin Pavel V
ITMO University, 9 Lomonosova Street, Saint Petersburg 191002, Russian Federation.
Tel Aviv University, Tel Aviv 69978, Israel.
ACS Appl Bio Mater. 2025 Jul 21;8(7):6145-6158. doi: 10.1021/acsabm.5c00680. Epub 2025 Jun 17.
Spider silk demonstrates an impressive balance of high strength and elasticity, which results from the hierarchical self-assembled structure of spider silk proteins during the fiber biosynthesis and spinning process. Enhancing the mechanical characteristics of spider silk fibers and imparting them with functional properties has garnered considerable attention. This challenge underscores the importance of developing strategies for modifying native spider silk. In this study, we introduce an approach to modify the structure and properties of spider silk fibers by injecting magnetite hydrosols directly into the spiders' silk glands. This results not only in the magnetic functionality of spider silk fibers but also in 82% increase in Young's compared to native spider silk, along with hardness of 1.30 MPa. To explore the nature of this phenomenon, we analyzed the difference in the topography of native spider silk and FeO-hybrid spider silk, as well as their corresponding mechanical behavior at the nanoscale. Additionally, we studied the changes in structure, composition, and morphology caused by the inclusion of magnetic nanoparticles. Our findings demonstrate that the polar and hydrophobic interactions between FeO nanoparticles and the amino acid residues in spider silk could influence Young's modulus and hardness of the FeO/spider silk hybrid fibers by promoting the protein conformation from an amorphous phase to β-sheets. This can only be achieved when nanomaterials are integrated into the structure within the fiber. The developed approach enables the fabrication of modified spider silk fibers, which can aid in the fundamental study of native spider silk and the development of technologies to fully replicate the properties of native silk in the future. Furthermore, lightweight, flexible, but strong materials are critical in soft robotic applications, where these nanohybrid fibers not only ensure gentle manipulation and reliability, but also their magnetic properties allow for responsive movement and control.
蜘蛛丝展现出高强度与高弹性之间令人赞叹的平衡，这源于蜘蛛丝蛋白在纤维生物合成和纺丝过程中的分级自组装结构。增强蜘蛛丝纤维的机械性能并赋予其功能特性已引起了广泛关注。这一挑战凸显了开发修饰天然蜘蛛丝策略的重要性。在本研究中，我们引入了一种通过将磁铁矿水溶胶直接注入蜘蛛的丝腺来修饰蜘蛛丝纤维结构和性能的方法。这不仅使蜘蛛丝纤维具有磁功能，而且与天然蜘蛛丝相比，杨氏模量提高了82%，硬度达到1.30兆帕。为了探究这一现象的本质，我们分析了天然蜘蛛丝和FeO复合蜘蛛丝的表面形貌差异，以及它们在纳米尺度下相应的力学行为。此外，我们研究了磁性纳米颗粒的加入所引起的结构、组成和形态变化。我们的研究结果表明，FeO纳米颗粒与蜘蛛丝中氨基酸残基之间的极性和疏水相互作用可通过促进蛋白质构象从无定形相转变为β折叠片层来影响FeO/蜘蛛丝复合纤维的杨氏模量和硬度。只有当纳米材料整合到纤维内部结构中时才能实现这一点。所开发的方法能够制造修饰后的蜘蛛丝纤维，这有助于对天然蜘蛛丝进行基础研究，并在未来开发出能完全复制天然丝性能的技术。此外，轻质、灵活但强度高的材料在软机器人应用中至关重要，在这些应用中，这些纳米复合纤维不仅确保了轻柔操作和可靠性，而且它们的磁性还允许进行响应式运动和控制。
