ELECTRIC CHARACTERISTICS OF HYBRID POLYMER MEMBRANES COMPOSED OF 2 LIPID SPECIES

Electric characteristics of hybrid polymer membranes composed of two l ipid species were studied, where one lipid species is positively charg ed in aqueous solution and the other is negatively charged. As a resul t, it was found that the hybrid membranes responded to taste substance s in different ways according to the molar mixing ratio of these two k inds of lipids, and also showed different response characteristics fro m those of the single-lipid membranes. The membranes with the mixing r atio around 50% exhibited the largest responses to HCl (sourness) and monosodium glutamate (umami). Moreover, good quantitative agreements w ith the observed data on the response electric potential were obtained using a theory describing both the changes in surface electric potent ial and surface charge density with taste substances.