A lead(II)-selective PVC membrane based on a Schiff base complex of N,N'-bis(salicylidene)-2,6-pyridinediamine

PVC membrane electrodes for lead ion based on N,N'-bis(salicylidene)-2,6-pyridinediamine as membrane carrier were prepared. Among their membranes, a membrane electrode (m-3) containing o-NPOE as a plasticizer and 50 mol% additive displays an excellent Nernstian response (29.4 mV/decade) and the limit of detection of −log a (M) = 6.04 to Pb2+ in Pb(NO3)2 solutions at room temperature. It has a rapid response time within 10 s over the entire concentration range. The proposed electrode revealed good selectivity and response for Pb2+ over a wide variety of other metal ions in a pH 5.0 buffer solutions, and good reproducibility of base line in subsequent measurements.