Silver has an important role in electrical and electronic applications, photographic film production, manufacturing of fungicides and drugs [1]. Potentiometric detectors based on ion selective electrodes are especially suited for fast, accurate, reproducible and selective determination of metal ions [2]. A silver selective electrode was prepared based on PVC membrane and 5-(4- dimethylaminobenzyliden)rhodanin as an ionophore. Several influential parameters on the electrode performance were optimized. With the optimized composition (PVC:30%; NPOE:61%; NaTBP: 6%; Ionophore:3%), the electrode shows a slope of 56.5 mV/dec over the concentration range of 1.0 × 10-5 to 1.0 × 10-2 M. the detection limit of the electrode based on the intersection of the extrapolated linear response part and horizontal part of the electrode was 1×10-5. This sensor has a short response time of 15 s and could be used in the pH range of 2-10. The electrode was applied for determination of silver ion in water samples.

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