In recent years, cyclodextrin polymeric nanoparticles have been designed to introduce new properties and extend their medical applications. Based on the features of cyclodextrins, we derivatized cross‐linked cyclodextrin polymers with histidine or carcinine moieties. We found that amylases do not hydrolyze cyclodextrin polymers. The new polymers can form copper(II) complexes and may act as nanochelators to counteract copper(II) dyshomeostasis‐related diseases. Furthermore, the copper(II) complexes show superoxide dismutase activity, similar to free carcinine and histidine complexes. The antioxidant biological activity of the copper(II) complex formed in situ may protect cells from oxidative damage related to copper dyshomeostasis.