CHROMOGENIC CALIX[4]ARENE AS IONOPHORE FOR POTENTIOMETRIC AND OPTICALSENSORS

Chromogenic calix[4]arene derivative was synthesized and tested as an ionophore for potentiometric and optical sensors. Distinct sodium sele ctivity was observed with this ionophore based, plasticized PVC membra nes in potentiometric measurements suggesting their utility for biolog ical applications. Optode membranes exhibited sodium sensitivity in th e 5 x 10(-2)-10(-4)M concentration range. The optical sensitivity was improved by the use of an internal, lipophilic base (TDDA). The operat ion of the optical sensor is in accordance with the ion-exchange theor y.