A Biomimetic Lubricating Nanosystem with Responsive Drug Release for Osteoarthritis Synergistic Therapy.

Osteoarthritis (OA) is associated with lubrication failure of articular cartilage and severe inflammatory response of joint capsule. Synergistic therapy combining joint lubrication and anti-inflammation emerges as a novel treatment of OA. In this study, bioinspired by ultra-low friction of natural articular synovial fluid and mussel adhesion chemistry, a biomimetic nanosystem with dual functions of enhanced lubrication and stimuli-responsive drug release was developed. A dopamine mediated strategy realized one step biomimetic grafting of hyaluronic acid on fluorinated graphene. The polymer modified sheets exhibited highly efficient near-infrared absorption, and showed steady lubrication with a long-time under various working conditions, in which the coefficient of friction was reduced by 75% compared to H 2 O. Diclofenac sodium with a high loading capacity of 29.2% was controllably loaded, and responsive and sustained drug release was adjusted by near-infrared light. Cell experiments revealed that the lubricating nanocarrier was taken up by endocytosis, and anti-inflammation results confirmed that the nanosystem inhibited osteoarthritis deterioration by up-regulating cartilage anabolic gene and down-regulating catabolic proteases and pain-related gene. Our work proposes a promising biomimetic approach to integrate polymer modified fluorinated graphene as a novel dual-functional nanosystem for effective synergistic therapy of OA. This article is protected by copyright. All rights reserved.