Analytical Sciences

Abstract − Analytical Sciences, 18(2), 133 (2002).

Clotrimazole-Triiodide Ion Associationas an Ion Exchanger for a Triiodide Ion-Selective Electrode
Khalil FARHADI  and RaminMALEKI
Department of Chemistry, Faculty ofScience, Urmia University, Urmia, Iran
A novel triiodide ion-selective electrodebased on a clotrimazole-triiodide ion pair as a membrane carrier wasprepared. It has a linear response to triiodide from 8 x 10-6to 5 x 10-3 M with a slope of -68.9 mV per decade and adetection limit of 5 x10-6 M. The electrode response isindependent of the pH of the solution in the pH range 2 - 9. It has a veryshort response time and can be used for at least 3 months without anyconsiderable divergence in the potentials. The proposed sensor revealedvery good selectivities for I3- over a variety ofother anions. It was used as an indicator electrode in the potentiometrictitration of triiodide ions and in an indirect potentiometric determinationof clotrimazole in pharmaceutical preparations.