Oxovanadium(IV) heteromacrocyclic complexes as ionophores for iodide-selective electrodes

Abstract

Abstract Highly selective poly(vinyl chloride) (PVC) membrane electrodes, based on oxovanadium(IV) complexes of heteromacrocyclic compounds as new iodide-selective ionophores for ion-selective electrodes (ISEs), were fabricated with a composition of PVC (28.1 wt%), plasticizers (69.3 wt%), ionophores (2.6 wt%), and cation excluders (15 mol% relative to the ionophore). The electrode prepared from oxovanadium(IV) tetraphenyl porphyrin with 2-nitrophenyl octyl ether (o-NPOE) as the membrane solvent and tetradodecylammonium chloride (TDDACl) as the cation excluder was found to exhibit the best sensitivity over a wide concentration range from 5.0 × 10–7 to 2.1 × 10–2 M with a Nernstian response of −59.02 mV per decade and the highest ion-selectivity toward I− ions over perchlorate ions (I−/ClO4− = 91).