A possibility to recognize chirality by an excitable artificial liquid membrane.

Studies were made on oscillations across a liquid membrane consisting of an oil layer, nitrobenzene containing picric acid, between two aqueous layers: a solution of 1.5 M ethanol and 5 mM optically-active cationic detergent, the D- or L-form of N-alpha-methylbenzyl-N,N-dimethylmyristylammonium bromide, on the left and 0.1 M D- or L-form of various ligands, such as glucose, arabinose, alanine, glutamic acid, threonine, leucine, proline, or phenylalanine on the right. This system showed sustained rhythmic oscillations of electrical potential of 200-300 mV with intervals of the order of 1 min. The frequency of oscillations depended on the combination of chiralities of the detergent and ligand. This means that the two forms (D and L) of chiral ligands can be distinguished by differences in the electrical response of the liquid membrane.