Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel.
Science. 2020 Oct 16;370(6514):335-338. doi: 10.1126/science.aay8276.
The lubrication of hydrogels arises from fluid or solvated surface phases. By contrast, the lubricity of articular cartilage, a complex biohydrogel, has been at least partially attributed to nonfluid, lipid-exposing boundary layers. We emulated this behavior in synthetic hydrogels by incorporating trace lipid concentrations to create a molecularly thin, lipid-based boundary layer that renews continuously. We observed a 80% to 99.3% reduction in friction and wear relative to the lipid-free gel, over a wide range of conditions. This effect persists when the gels are dried and then rehydrated. Our approach may provide a method for sustained, extreme lubrication of hydrogels in applications from tissue engineering to clinical diagnostics.
水凝胶的润滑来自于流体或溶剂化的表面相。相比之下,关节软骨的润滑性能(一种复杂的生物水凝胶)至少部分归因于非流体、暴露脂质的边界层。我们通过在合成水凝胶中加入微量脂质浓度来模拟这种行为,从而形成一层分子级薄的、基于脂质的边界层,它可以持续更新。在广泛的条件下,与无脂质凝胶相比,摩擦和磨损减少了 80%至 99.3%。当凝胶干燥然后再水合时,这种效果仍然存在。我们的方法可能为从组织工程到临床诊断等应用中水凝胶的持续、极端润滑提供一种方法。