Bioactive glasses-based nanoenzymes composite double-network hydrogel with ROS scavenging for bone tissue engineering

Reactive oxygen species (ROS) plays a crucial role in normal physiological activities. But hypoxia-induced oxidative stress leads to excessive accumulation of ROS in the microenvironment of bone defects, which could hinder tissue repair. Therefore, the regulation of ROS is essential for promoting bone repair. Herein, a mesoporous bioactive glass-based nanoenzyme (MBGNs@PDA@MnO 2 ) with the property to manage ROS was designed and prepared. The MBGNs@PDA@MnO 2 powders displayed excellent mineralization properties and antioxidation activity. The hydrogel with double-network structure were constructed and synthesized using oxidized chitosan (OCS) and dopamine-grafted gelatin (Gel-DA) by Schiff-base and oxidative coupling reaction, and then MBGNs@PDA@MnO 2 was incorporated into the hydrogel. Cell experiments demonstrated that the composite hydrogels could effectively reduce intracellular ROS level, and had good cytocompatibility and osteogenesis promotion capability. Hence, the composite hydrogels with ROS regulation had the potential to be a new strategy for the treatment of bone defects.