Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China.
The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, Engineering Research Center of Eco-friendly Polymeric Materials, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
Biomacromolecules. 2024 Jun 10;25(6):3554-3565. doi: 10.1021/acs.biomac.4c00072. Epub 2024 May 10.
Hydrogels are considered as a potential cartilage replacement material based on their structure being similar to natural cartilage, which are of great significance in repairing cartilage defects. However, it is difficult for the existing hydrogels to combine the high load bearing and low friction properties (37 °C) of cartilage through sample methods. Herein, we report a facile and new fabrication strategy to construct the PNIPAm/EYL hydrogel by using the macrophase separation of supersaturated -isopropylacrylamide (NIPAm) monomer solution to promote the formation of liposomes from egg yolk lecithin (EYL) and asymmetric template method. The PNIPAm/EYL hydrogels possess a relatively high compressive strength (more than 12 MPa), fracture energy (9820 J/m), good fatigue resistance, lubricating properties, and excellent biocompatibility. Compared with the PNIPAm hydrogel, the friction coefficient (COF 0.046) of PNIPAm/EYL hydrogel is reduced by 50%. More importantly, the COF (0.056) of PNIPAm/EYL hydrogel above lower critical solution temperature (LCST) does not increase significantly, exhibiting heat-tolerant lubricity. The finite element analysis further proves that PNIPAm/EYL hydrogel can effectively disperse the applied stress and dissipate energy under load conditions. This work not only provides new insights for the design of high-strength lubricating hydrogels but also lays a foundation for the treatment of cartilage injury as a substitute material.
水凝胶因其结构类似于天然软骨而被认为是一种有潜力的软骨替代材料，在修复软骨缺陷方面具有重要意义。然而，现有的水凝胶很难通过样品方法将软骨的高承载能力和低摩擦特性（37°C）结合起来。在此，我们报告了一种简便的新制造策略，通过使用过饱和 -异丙基丙烯酰胺（NIPAm）单体溶液的相分离来促进蛋黄卵磷脂（EYL）形成脂质体，并采用不对称模板法来构建 PNIPAm/EYL 水凝胶。PNIPAm/EYL 水凝胶具有较高的压缩强度（超过 12 MPa）、断裂能（9820 J/m）、良好的耐疲劳性、润滑性能和优异的生物相容性。与 PNIPAm 水凝胶相比，PNIPAm/EYL 水凝胶的摩擦系数（COF 0.046）降低了 50%。更重要的是，PNIPAm/EYL 水凝胶在低于低临界溶液温度（LCST）以上时的 COF（0.056）并没有显著增加，表现出耐热润滑性。有限元分析进一步证明，PNIPAm/EYL 水凝胶在负载条件下可以有效地分散施加的应力并耗散能量。这项工作不仅为高强度润滑水凝胶的设计提供了新的思路，也为作为替代材料治疗软骨损伤奠定了基础。
