Covalently assembled ultrathin polymer nanocapsules to mimic a multienzyme-cascade antioxidative system

Abstract

Ultrathin selenium-containing manganese-porphyrin-based polymer nanocapsules with both superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity were successfully constructed through a covalent assembly strategy for mimicking the natural multienzyme-cascade antioxidative system. In this case, Mn-CATPyP (4,4′,4′′,4′′′-(Mn-porphyrin-5,10,15,20-tetrayl)tetrakis (1-(6-carboxyhexyl)pyridin-1-ium)) served as an SOD mimic, while Se-diamine(2,2′-selenobis(ethan-1-amine)) was designed to mimic GPx. The functionalized system shows good biocompatibility for efficient cellular internalization. In vitro experiments also demonstrated the excellent ROS-scavenging ability of the polymer nanocapsules in cell protection against oxidative stress. This artificial cooperative antioxidant model may help us to understand the natural antioxidative process.