Artificial cation-conducting channels: design, synthesis, and characterization.

A nonpeptidic, cation-conducting channel has been designed, synthesized, and evaluated. The channel was found to conduct protons and Na+ through phospholipid bilayers. The evaluation of Na+ transport was conducted using a dynamic 23Na-NMR (nuclear magnetic resonance) in phospholipid vesicles and a planar bilayer using a patch clamp amplifier. Several control compounds were prepared to determine which of the structural "modules" were necessary. Experiments using fluorescent residues and fluorescence energy transfer were undertaken to locate the channel within the bilayer and to demonstrate that the channel functions as a monomeric unit.