Reversible Zn ²⁺ ‐Activated Channel Transport Through Monomer‐Dimer Interconversion of Rotaxane

Abstract Inspired by natural ligand‐gated ion channels, artificial counterparts are of great interest for understanding biological transport mechanisms and developing bioinspired functional systems. Here, we report a Zn 2+ ‐activated artificial ion channel from a [2]rotaxane. Its key components are: i) a sliding bis(benzo‐18‐crown‐6) unit for K⁺ transport and ii) a Zn 2+ ‐responsive terpyridine thread that provides gating control. The monomeric rotaxane functions as an inactive carrier, whereas Zn 2+ ‐induced dimerization triggers a switch to a highly efficient channel transport mode. This transition is fully reversible with Zn 2+ and competitive ligands. As the first biomimetic Zn 2+ ‐gated artificial ion channel, this work provides a novel design strategy for ligand‐regulated transmembrane transporters.