Microporous Organic Nanoparticles Anchoring CeO₂ Materials: Reduced Toxicity and Efficient Reactive Oxygen Species-Scavenging for Regenerative Wound Healing

This work shows that microporous organic polymer can be applied to the engineering of CeO₂-based antioxidant nanomaterials for in vivo regenerative wound healing. Whilst nanoparticulate CeO₂ has shown excellent redox quenching of reactive oxygen species (ROS) because it is rich in oxygen defects and Ce³⁺ species, it has a strong tendency to form aggregates because it is a kinetic intermediate of bulk materials. Anchoring of nanoparticulate CeO₂ on suitable supports can be an efficient anti-aggregation strategy. In this work, CeO₂ nanoparticles were immobilized on microporous organic nanoparticles (MONPs) to form MONP@CeO₂ nanocomposites. Compared to CeO₂ materials, the MONP@CeO₂ nanocomposites showed not only efficient ROS scavenging in in vivo regenerative wound healing but also reduced cytotoxicity in in vitro cell studies, due to the efficient distribution and dilution effect of CeO₂ nanomaterials.