Abstract

Silk fibroin (SF) from Bombyx mori is a natural polymer with exceptional biocompatibility, low immunogenicity, and ease of processability. SF-based hydrogels have been identified as one of the most attractive candidate scaffolds for tissue engineering and can be fabricated through various physical or chemical crosslinking approaches. However, conventional SF hydrogels may suffer from several major drawbacks, such as structural inhomogeneity, poor mechanical properties or utilization of cytotoxic reagents. Herein, a dually crosslinked SF-based composite hydrogel with enhanced strength and elasticity was fabricated by inducing the formation of uniform and small β-sheet structures by sonication in a restricted enzymatic precrosslinked network. The composite hydrogel not only demonstrated concentration-dependent stiffness variation but also exhibited time-dependent changes in toughness behavior. Moreover, subsequent experimental results revealed that the hydrogels exhibit other advantages, including high water retention capacity and long-term stability under physiological conditions. Finally, a three-dimensional (3 D) construct of the cell-laden hydrogel was fabricated, confirming that the composite hydrogel could provide a biocompatible microenvironment with dynamically changing mechanical properties. The combination of physical and enzymatic crosslinking strategies contributes to a biocompatible composite hydrogel with unique mechanical properties that holds great potential for use in tissue engineering and regenerative medicine.

摘要

从丝心蛋白（SF）家蚕是一种天然聚合物，具有出色的生物相容性、低免疫原性和易加工性。SF 基水凝胶已被确定为最有吸引力的组织工程候选支架之一，可以通过各种物理或化学交联方法制造。然而，传统的 SF 水凝胶可能存在几个主要缺点，例如结构不均匀、机械性能差或使用细胞毒性试剂。在此，通过在受限酶促预交联网络中通过超声处理诱导形成均匀且小的 β-折叠结构，制备了具有增强强度和弹性的双交联 SF 基复合水凝胶。复合水凝胶不仅表现出浓度依赖性刚度变化，而且还表现出韧性行为的时间依赖性变化。此外，随后的实验结果表明，水凝胶还表现出其他优势，包括高保水能力和生理条件下的长期稳定性。最后，制造了充满细胞的水凝胶的三维 (3D) 构造，证实复合水凝胶可以提供具有动态变化的机械性能的生物相容性微环境。物理和酶促交联策略的结合有助于形成具有独特机械性能的生物相容性复合水凝胶，在组织工程和再生医学中具有巨大的应用潜力。随后的实验结果表明，水凝胶表现出其他优势，包括高保水能力和生理条件下的长期稳定性。最后，制造了充满细胞的水凝胶的三维 (3D) 构造，证实复合水凝胶可以提供具有动态变化的机械性能的生物相容性微环境。物理和酶促交联策略的结合有助于形成具有独特机械性能的生物相容性复合水凝胶，在组织工程和再生医学中具有巨大的应用潜力。随后的实验结果表明，水凝胶表现出其他优势，包括高保水能力和生理条件下的长期稳定性。最后，制造了充满细胞的水凝胶的三维 (3D) 构造，证实复合水凝胶可以提供具有动态变化的机械性能的生物相容性微环境。物理和酶促交联策略的结合有助于形成具有独特机械性能的生物相容性复合水凝胶，在组织工程和再生医学中具有巨大的应用潜力。制造了载有细胞的水凝胶的三维 (3D) 结构，证实复合水凝胶可以提供具有动态改变机械性能的生物相容性微环境。物理和酶促交联策略的结合有助于形成具有独特机械性能的生物相容性复合水凝胶，在组织工程和再生医学中具有巨大的应用潜力。制造了载有细胞的水凝胶的三维 (3D) 结构，证实复合水凝胶可以提供具有动态改变机械性能的生物相容性微环境。物理和酶促交联策略的结合有助于形成具有独特机械性能的生物相容性复合水凝胶，在组织工程和再生医学中具有巨大的应用潜力。