Electric characteristics of a Millipore-DOPH membrane composed of a Milliporefilter whose pores are adsorbed with a synthetic lipid analogue, dioleylphosphate (DOPH) have been investigated. The oscillation phenomenon of the membrane resistance produced by a pressure stimulus is simulating a part of a mechanoreceptor membrane. It is difficult, however, to maintain changes of the resistance more than 3 days, because the DOPH embedded in the Millipore filter that serves as a supporting body dissolves easily in a salt solution. In this study, a PVC (polyvinylchloride)-DOPH new artificial membrane which used a high-polymer PVC instead of the Milliporefilter was made. Durability of the membrane improved in this substitution for a long period more than 120days. An electric equivalent circuit of a cell membrane is simply shown by an electric resistance and capacitance. The Millipore-DOPH membrane had characteristics of a Ca
2+ion sensor in the former study. This paper experimentally makes it clear that the electric resistance and capacitance of the new PVC-DOPH membrane changed with Ca
2+ion as observed in the Millipore-DOPH membrane, and that this characteristic of the PVC-DOPH membrane was kept for long. Futhermore, responses of the electric resistance and capacitance to the concentration of five basic taste substances, in addition to Ca
2+ion, i. e., a sucrose (sweetness), a NaCl (saltiness), a HCl (sourness), a quinine (bitterness) and a mono-sodium L-glutamate (umami) were investigated by the new artificial membrane. These results suggest that the PVC-DOPH membrane had a possibility to be applied to a taste sensor material which is excellent in durability.
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