A Visible‐Light‐Regulated Chloride Transport Channel Inspired by Rhodopsin

Inspired by the light‐regulating capabilities of naturally occurring rhodopsin, we have constructed a visible‐light‐regulated Cl − ‐transport membrane channel based on a supramolecular host–guest interaction. A natural retinal chromophore, capable of a visible‐light response, is used as the guest and grafted into the artificial channel. Upon introduction of an ethyl‐urea‐derived pillar[6]arene (Urea‐P6) host, threading or de‐threading of the retinal and selective bonding of Cl − can be utilized to regulate ion transport. Based on the visible‐light responsiveness of the host–guest interaction, Cl − transport can be regulated by visible light between ON and OFF states. Visible‐light‐regulated Cl − transport as a chemical model permits to understand comparable biological ion‐selective transport behaviors. Furthermore, this result also supplies a smart visible‐light‐responsive Cl − transporter, which may have applications in natural photoelectric conversion and photo‐controlled delivery systems.