Researchers have developed synthetic ion channels that can mimic the activity of natural ion channels embedded in cell membranes1. These synthetic ion channels could potentially be used as drug-delivery systems and for studying ion transport across cell membranes.

Synthetic ion channels produced by mimicking natural ion channels could provide insights into how pore-forming channel proteins work. The researchers produced synthetic ion channels by linking fluorescent, water-loving and fat-loving molecules to guanosine-derived compounds. They then inserted these artificial ion channels into bilayer lipid membranes and measured their conductance and ion transport properties in buffer solutions containing sodium, potassium and caesium ions using voltage-clamp experiments.

The conductance depends on the sizes of both the pores and the ions. Small ion channels showed conductance in the range 0.1 to 0.8 nanosiemens (nS) for solutions containing potassium and caesium ions. In the presence of sodium ions, the channels exhibited higher conductances of up to 5 nS. The pore size and conductance of the ion channels can be modulated by modifying the linking molecules.

"These pore-forming artificial ion channels could be useful for finding a new generation of antimicrobial and anticancer agents, and thus help to develop new cancer treatments and alternatives to drug-resistant bacteria," says Jyotirmayee Dash, a senior author of the study.