Tilieke Mili, Shu Xiong, Chen Lei, Jie Yongsheng, Zheng Rui, Zhang Zheng, Numata Keiji, Guan Juan, Shao Zhengzhong
International Research Center for Advanced Structural and Biomaterials, School of Materials Science & Engineering, Beihang University, Beijing 100191, People's Republic of China.
Beijing Research Institute of Orthopedics and Traumatology, Beijing Jishuitan Hospital, Capital Medical University, Beijing 100035, China.
Int J Biol Macromol. 2025 Jul;318(Pt 4):145266. doi: 10.1016/j.ijbiomac.2025.145266. Epub 2025 Jun 14.
Developing durable hydrogels for cartilage replacement remains a critical challenge. UV-crosslinkable hydrogels from methacrylated silk fibroin (SFMA) or polyacrylamide (PAM) have shown great potential in biomedical applications. However, either pure SFMA or PAM hydrogels lack adequate strength for structural applications in vivo. Herein, we introduced SFMA as a biomacromolecular linker and biocompatible component into the PAM-based polymer that was in situ polymerized under UV irradiation within 10 s. The prepared SFMA-AM hydrogel consisting of extensive covalent and hydrophobic interactions exhibited excellent elasticity and strength. The SFMA-AM hydrogel could be further reinforced by ethanol treatment, which triggered conformational transitions and enhanced hydrogen bonding within the dynamic physical network. The synthesized SFMA-AM ET hydrogel exhibited a compressive strength of 4.4 MPa, a compressive modulus of 580 kPa, and excellent fatigue resistance (over 800 cycles) without structural failure. In vitro cytocompatibility evaluations and in vivo subcutaneous implantation models confirmed excellent biocompatibility of both SFMA-AM and SFMA-AM ET hydrogels, demonstrating silk fibroin's beneficial effects in cell proliferation and tissue regeneration. The strategy of SFMA modification could be generalized to improve the mechanical performance and biocompatibility of conventional acrylic amide-based hydrogels, thereby broadening the biomedical applications of PAM.
开发用于软骨替代的耐用水凝胶仍然是一项严峻挑战。由甲基丙烯酰化丝素蛋白（SFMA）或聚丙烯酰胺（PAM）制成的可紫外线交联水凝胶在生物医学应用中显示出巨大潜力。然而，纯SFMA或PAM水凝胶在体内结构应用中缺乏足够的强度。在此，我们将SFMA作为生物大分子连接体和生物相容性组分引入基于PAM的聚合物中，该聚合物在紫外线照射下10秒内原位聚合。制备的由广泛的共价和疏水相互作用组成的SFMA-AM水凝胶表现出优异的弹性和强度。SFMA-AM水凝胶可通过乙醇处理进一步增强，这会引发构象转变并增强动态物理网络内的氢键。合成的SFMA-AM ET水凝胶表现出4.4兆帕的抗压强度、580千帕的压缩模量以及出色的抗疲劳性（超过800次循环）且无结构破坏。体外细胞相容性评估和体内皮下植入模型证实了SFMA-AM和SFMA-AM ET水凝胶均具有出色的生物相容性，证明了丝素蛋白在细胞增殖和组织再生方面的有益作用。SFMA改性策略可推广用于改善传统丙烯酸酰胺基水凝胶的机械性能和生物相容性，从而拓宽PAM的生物医学应用。
