Synthetic Ion Channel Formed by Multiblock Amphiphile with Anisotropic Dual-Stimuli-Responsiveness

摘要

Transmembrane proteins within biological membranes exhibit varieties of important functions that are vital for many cellular activities, and the development of their synthetic mimetics allows for deep understanding in related biological events. Inspired by the structures and functions of natural ion channels that can respond to multiple stimuli in an anisotropic manner, we developed multiblock amphiphile V_F in this study. When V_F was incorporated into the lipid bilayer membranes, V_F formed a supramolecular ion channel whose ion transport property was controllable by the polarity and amplitude of the applied voltage. Microscopic emission spectroscopy revealed that V_F changed its molecular conformation in response to the applied voltage. Furthermore, the ion transport property of V_F could be reversibly switched by the addition of (R)-propranolol, an aromatic amine known as an antiarrhythmic agent, followed by the addition of β-cyclodextrin for its removal. The highly regulated orientation of V_F allowed for an anisotropic dual-stimuli-responsiveness for the first time as a synthetic ion channel.