Synergistic hydration lubrication of polyurethane meniscus based on zwitterionic structures and hyaluronic acid

In this study, polyurethanes with graded sulfobetaine content (PU-SBs) were employed to resolve the high friction of artificial menisci. Under the simulated gait of knee joints, the coefficient of friction of PU-SB60 in hyaluronic acid (HA) aqueous solution was similar to that of the native meniscus. Importantly, this phenomenon was caused by synergistic hydration lubrication based on sulfobetaine groups and HA, that a thicker and stronger hydration layer was preferred to form quickly on the surfaces of HA-adsorbed PU-SB60 and was harder to be destroyed by the friction force. Furthermore, PU-SB60 exhibited both excellent modulus and long-term low cytotoxicity. Therefore, PU-SB60 has the potential to be applied for artificial menisci due to its overall performance.