title: Neutral-carrier-type potassium ion-selective electrodes based on polymer-supported liquid-crystal membranes for practical use.
abstract: Polymer-supported liquid-crystal membranes have been designed for neutral-carrier-type potassium ion-selective electrodes, aiming for practical applications of high-performance liquid-crystalline membrane ion sensors. Two types of polymer-supported liquid-crystal membranes were tested for their usefulness; one is microporous poly(tetra fluoroethylene) (PTFE) membranes impregnated by thermotropic liquid-crystalline compounds, and another is poly(methyl methacrylate) (PMMA) membrane dispersing the same liquid-crystalline compounds. Both of the polymer-supported liquid-crystal membranes containing a liquid-crystalline benzo-15-crown-5 neutral carrier as well as a lipophilic anion excluder work well as ion-sensing membranes for potassium ion-selective electrodes, the ion selectivities of which can be switched by the measurement temperatures. Specifically, PTFE-impregnated liquid-crystal membranes are better than the PMMA-dispersed ones in the sensitivity and selectivity of the resulting ion electrodes. A potassium ion assay in blood sera has proved that neutral-carrier-type ion-selective electrodes based on the polymer-supported liquid-crystal membranes are reliable for practical uses.
authors.affiliation: Department of Applied Chemistry, Faculty of Systems Engineering, Wakayama University, Sakaedani 930, Wakayama, Wakayama 640-8510, Japan.
authors.forename: Syusuke
authors.initials: S
authors.lastname: Oosaki
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kawai
authors.forename: Setsuko
authors.initials: S
authors.lastname: Yajima
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kimura