Discreteness of Conductance Change in Black Lipid Films

The mechanisms by which inorganic ions cross biological membranes are still effectively unknown. However, it has become very clear during the past few years that the proteins or other macromolecules in the membrane are much more likely to be involved in this process than are the lipids. Thus, experiments with artificial lipid membranes have revealed no indicatfon of the necessary ion transfer or ion selectivity properties among the naturally occurring lipids, whereas many small macromolecules, including some polypeptides, are known to be entirely adequate in these respects