Iodide-Selective PVC Membrane Electrode Based on Copper Complex of 2-Acetylthiophene Semicarbazone as Carrier

A highly selective poly(vinyl chloride) (PVC) membrane electrode based on copper (II) complex of 2-acetylthiophene semicarbazone as a new carrier for iodide-selective electrode is fabricated with the composition of PVC (30 %), plasticizer (64 %), ionophore (4 %) and lipophilic additive (2 %). The prepared electrode has been found to exhibit the best sensitivity over a wide concentration range of 1x10(-6) to 3.2x10(-2) M with a near Nernstian response of 57.2 mV per decade over a wide pH range of 2.5 - 10.5. The detection limit for the electrode was found to be 5.50x10(-7) M with the response time of 15 s and can be used for at least 3 months without any considerable divergence in its potential response.