Light-Controlled Conductive Molecular Wire in an Artificial Lipid Membrane.

In this work, we investigate a novel photochromic azobenzene derivative, TC827, which exhibits a unique photoelectric response when embedded in artificial lipid membranes. By combining spectroscopic, electrochemical, and molecular simulation analyses, we demonstrate that TC827 forms light-controlled "molecular wires" in its trans conformation, resulting in a significant increase in membrane conductivity under dark conditions, which is fully reversible, as light-induced cis isomerization suppresses the conductivity enhancement. This behavior is fundamentally different from previously studied amphiphilic azobenzene derivatives, whose effect on lipid membranes is usually attributed to their ability to increase permeability by disrupting membrane packing, leading to a current increase in the cis state under irradiation. In our system, the increase in conductivity is not associated with membrane destabilization due to the chemical structure of TC827 molecule, which lacks long alkyl chains and features a π-conjugated structure. These findings underline the potential of structurally simple, short-chain photo-switchable molecules to modulate membrane properties through charge transport mechanisms induced by light, offering a new pathway toward the design of optoelectronic bio-interfaces.