A New enzymatic receptor to be used in a biosensor

An artificial lipid membrane which incorporated an enzyme was prepared and used for the molecular recognition element of a sensor. This membrane constituted alanine aminotransferase and an acetylcellulose membrane containing phospholipid and cholesterol. The membrane exhibited specific response to the substrate, resulting in a change in membrane potential. In the experiment, this enzyme was used as an L-alanine receptor, since the enzyme does not show catalytic activity under restricted conditions. When L-alanine was applied to the membrane, surface charge density increased with application time. Membrane potential appeared to be shifted mainly by the change of surface charge density caused by formation of an enzyme-alanine complex.