Beyond the Source: Nanozyme-like Carbon Dots Derived from Cherry Tomato Mitigate Ocular Oxidative Stress

Ocular tissues are subject to heightened oxidative stress due to prolonged environmental exposure and intrinsic metabolic radical generation. Although fruits such as cherry tomatoes are rich in natural antioxidants, their poor bioavailability and low stability limit clinical utility. To address this, we developed amphiphilic carbon dots (TM-CDs) via a microwave-assisted synthesis using fresh cherry tomato juice as the single source. The resulting TM-CDs exhibit bright fluorescence, high stability, excellent biocompatibility, multienzyme-like activity, and potent free radical scavenging capacity. Notably, TM-CDs showed significant ocular accumulation in zebrafish, enabling efficient scavenging of diverse ROS species and the mitigation of oxidative damage. Experimental results indicated that TM-CDs not only ameliorated ocular dysplasia in zebrafish induced by cysteamine hydrochloride but also maintained ocular redox homeostasis by upregulating superoxide dismutase (SOD) activity and glutathione (GSH) content, while reducing malondialdehyde (MDA) content. Consequently, the visual behavior of zebrafish, such as the mirror-biting duration, returns to normal. This coordinated multimechanistic recovery highlights the potential of biomass-derived carbon dots as a next-generation nanotherapeutic strategy for oxidative ocular disorders.