Good ion-selective electrodes (ISEs) possess many advantages over traditional methods of analysis and provide accurate, reproducible, fast, and regular selective determination of various ionic species. In addition, ion-selective electrodes allow nondestructive, on-line monitoring of particular ions in a small volume of sample without any pretreatment. Because of these merits, the use of ISEs is increasing day by day in medicinal, environmental, agricultural, and industrial fields[1−3]. In this work a novel cerium cation polymeric membrane selective electrode based on a new synthetic ligand incorporated into a polyvinylchloride (PVC) membrane has been developed. The membranes were prepared by dissolving optimized amounts of PVC, plasticizer, NPOE, and ionophore in about 0.8 mL of THF. The mixture was shaken vigorously and the clear solution was poured into a glass dish 5 cm in diameter. The solvent was allowed to evaporate at room temperature, until an oily concentrated mixture was obtained. For preparation of the cation selective electrode, a Pyrex tube (3 mm o.d.) was dipped into the mixture for 5 s so that a nontransparent membrane was formed. The tube was then filled with internal filling solution (1.0 ×10−3 M Ce(NO3)3). The electrode was finally conditioned by soaking in 1.0 × 10−3 M Ce(NO3)3. A silver/silver chloride electrode was used as an internal reference electrode. The electrode exhibits a good Nerenstian slope over the concentration range 1.0×10-6 to 1.0×10-1M. The effects of the pH and the possible interfering cations and anions were investigated and the optimized conditions for electrode were evaluated. The response time of the electrode is about 15s. The electrode was applied as indicator electrode in ptentiometric titrations.

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