A Degradable Macromolecular Antioxidant for Efficient Arthritis Treatment.

Reactive oxygen species (ROS) are vital but harmful in excess, and numerous small molecule antioxidants (e.g., polyphenols) can help to maintain an optimal ROS balance. Considering factors like biocompatibility, it is more commonly preferred to transform these natural antioxidants into nanoscavengers through a macromolecular engineering strategy. However, conventional macromolecular antioxidants typically exhibit decreased scavenging capacity compared to monomers due to steric hindrance and oxidation during the polymerization. To tackle this issue, we developed robust degradable macromolecular nanoscavengers by polymerizing dopamine and 4-formylphenylboronic acid. Featuring boronate-catechol linkages, these nanoscavengers boost antioxidation by degrading and exposing functional groups in acidic or ROS environments, showing greater capacity than monomers and polydopamine nanoparticles. Those nanoscavengers were subsequently employed to temporomandibular joint osteoarthritis, suppressing both oxidative stress and inflammation to effectively alleviate the disease progression. This study offers new insights into the design and synthesis of degradable macromolecular antioxidants for inflammation treatment.