Lead-selective poly(vinyl cholride) membrane electrode based on piroxicam as a neutral carrier

An ion-selective electrode (ISE) for lead based on piroxicam as a suitable ionophor is described. The electrode responds to Pb2+ in a linear range from 1.0×10−5 to 1.0×10−1 mol l−1 with a slope of 30±0.2 mV per decade and a detection limit of (4.0±1.0)×10−6 mol l−1. The proposed electrode could be used in a pH range of 4.0–8.0. Selectivity coefficients were determined with the conventional fixed interference method (FIM), modified FIM combined with non-linear curve fitting of the Nickolskii–Eisenman equation and matched potential method (MPM). The electrode was successfully used for the direct determination of Pb2+ in solution and in potentiometric titration of Pb2+ ions.