Selective Ion Exchange Governed by the Irving–Williams Series in K₂Zn₃[Fe(CN)₆]₂ Nanoparticles: Toward a Designer Prodrug for Wilson’s Disease

The principle of the Irving–Williams series is applied to the design of a novel prodrug based on K₂Zn₃[Fe­(CN)₆]₂ nanoparticles (ZnPB NPs) for Wilson’s disease (WD), a rare but fatal genetic disorder characterized by the accumulation of excess copper in the liver and other vital organs. The predetermined ion-exchange reaction rather than chelation between ZnPB NPs and copper ions leads to high selectivity of such NPs for copper in the presence of the other endogenous metal ions. Furthermore, ZnPB NPs are highly water-dispersible and noncytotoxic and can be readily internalized by cells to target intracellular copper ions for selective copper detoxification, suggesting their potential application as a new-generation treatment for WD.