PVC-BASED 1,3,5-TRITHIANE COATED GRAPHITE ELECTRODE FOR DETERMINATION OF CERIUM(III) IONS

A novel Ce3+ ion-selective electrode based on 1,3,5-trithiane is described. The electrode was prepared by incorporating the ionophore into a plastisized PVC membrane, which was directly coated on the surface of a graphite electrode. The resulting electrode exhibits a Nernstian slope of 19.2±0.1mV/ decade over a wide concentration range (4.7 ×10-4 - 2.5 × 10-8 M) with a limit of detection of 2.0 × 10-8 M. It has a fast response time of about 10 s. The proposed electrode revealed excellent selectivities with respect to many transition, heavy and rare-earth metal ions. It was used as an indicator electrode in determination of F- ion in some mouth wash preparations with Ce3+ ion.