Engineering biocompatible carbon dots nano-enzymes hydrogel for efficient antioxidative and anti-inflammatory treatment of dry eye disease.

Dry eye disease (DED) is a complex and multifactorial ocular surface disease. Reactive oxygen species (ROS) are of pivotal importance in the inflammatory processes and biological dysfunction associated with DED. In this study, an injectable hydrogel, designated as OHACDgel, was created by combining oxidized HA-containing aldehyde groups (OHA) and gelation (gel) via dynamic covalent linkages of the hydrazine bonds, is employed as the carrier, while polyethylene imine-functionalized carbon dots (PEI-CD) can form dynamic chemical bonds with the hydrogel, thus prolonging the retention time of the ocular surface. OHACDgel has been demonstrated to diminish ROS overproduction markedly, reduce the expression of pro-inflammatory factors, inhibit the transformation of macrophages into a pro-inflammatory phenotype, reverse corneal epithelial defects, restore goblet cell function, and enhance tear secretion. Furthermore, the biocompatibility of OHACDgel has been demonstrated, presenting a rapid and straightforward therapeutic option for potential applications in DED.