Polymer Surfaces Group, Laboratory for Surface Science and Technology, Department of Materials, ETH Zürich, Zürich, Switzerland.
Tissue Engineering and Biofabrication Group, Department of Health Science and Technology, ETH Zürich, Zürich, Switzerland.
Angew Chem Int Ed Engl. 2018 Feb 5;57(6):1621-1626. doi: 10.1002/anie.201712534. Epub 2018 Jan 11.
Tissue-reactive graft copolymers were designed to protect the cartilage against enzymatic degradation and restore its lubrication properties during the early stages of osteoarthritis (OA). The copolymers feature a poly(glutamic acid) (PGA) backbone bearing hydroxybenzaldehyde (HBA) functions and cyclic poly(2-methyl-2-oxazoline) (PMOXA) side chains. PGA-PMOXA-HBA species chemisorb on the degraded tissue via Schiff bases and expose the biopassive and lubricious PMOXA cyclic grafts at the interface. The smaller hydrodynamic radius by cyclic PMOXA side chains coupled to the intrinsic absence of chain ends generate denser and more lubricious films on cartilage when compared to those produced by copolymers bearing linear PMOXA. Topology effects demonstrate how the introduction of cyclic polymers within tissue-reactive copolymers substantially improve their tribological and biopassive properties, suggesting a plethora of possible applications for cyclic macromolecules in biomaterials formulations.
组织反应性接枝共聚物旨在保护软骨免受酶降解，并在骨关节炎（OA）的早期恢复其润滑性能。共聚物的特点是聚（谷氨酸）（PGA）主链带有羟基苯甲醛（HBA）官能团和环状聚（2-甲基-2-恶唑啉）（PMOXA）侧链。PGA-PMOXA-HBA 物种通过席夫碱化学吸附在降解组织上，并在界面处暴露生物惰性和润滑性的 PMOXA 环状接枝。与带有线性 PMOXA 的共聚物相比，环状 PMOXA 侧链的较小流体力学半径与固有链末端的缺失相结合，在软骨上产生更致密和更润滑的薄膜。拓扑效应表明，在组织反应性共聚物中引入环状聚合物如何大大改善它们的摩擦学和生物惰性特性，这表明环状大分子在生物材料配方中有大量可能的应用。
