Electrical activity of artificial ion channels incorporated into planar lipid bilayers

Abstract

The ion transport ability in a planar lipid bilayer of a 21 amino acid peptide bearing six 21-crown-7 side chains is reported. The compound was designed to form an artificial ion channel by stacking the crown rings, when adopting an α-helical conformation in a bilayer membrane. All the derivatives of 1 exhibited membrane conductivity with the best results obtained with the unprotected analog 4. The latter showed typical single channel activity.

References

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