Mesomorphic Effect of Discotic-type Liquid-crystalline Compounds as Neutral Carriers on Potentiometric Ion-sensing Membranes
Mesomorphic porphyrin, 5,10,15,20-tetrakis(4-<I>n</I>-dodecylphenyl)porphyrin (C<SUB>12</SUB>TPPH<SUB>2</SUB>) and the cobalt complex C<SUB>12</SUB>TPPCo were used as neutral carriers of ion-selective electrodes (ISEs) to investigate the mesomorphic effect in potentiometric cation- and anion-sensing membranes. The selectivity coefficiency of a potentiometric cation-sensing membrane incorporating C<SUB>12</SUB>TPPH<SUB>2</SUB> was drastically affected by heat-induced phase transitions of ionophoric liquid-crystalline compound. This paper is the first report that proved the heat-induced phase transition of ionophoric liquid-crystalline compound in the potentiometric ion-sensing membrane. It is noteworthy that selectivity sequence of the potentiometric cation-sensing membrane is remarkable changed by the mesomorphic effect. Furthermore, mesomorphic effect on a potentiometric anion-sensing membrane incorporating C<SUB>12</SUB>TPPCo was also demonstrated.
- Chemistry letters
Chemistry letters 37(4), 450-451, 2008-04-05
The Chemical Society of Japan