Fabrication of an iron(III)-selective PVC membrane sensor based on a bis-bidentate Schiff base ionophore

摘要: A Fe3+ ion-selective membrane sensor was fabricated from polyvinyl chloride (PVC) matrix containing bis-bidentate Schiff base (BBS) as a neutral carrier, sodium tetraphenyl borate (NaTPB) anionic excluder, and o-nitrophenyloctyl ether (NPOE) plasticizing solvent mediator. The effects of the composition, pH, additive influence on response properties were investigated. best performance obtained with 32% PVC, 62.5% NPOE, 3% BBS, 2.5% NaTPB. electrode shows Nernstian behavior (slope 19.3 ± 0.6) over very wide iron ion concentration range (1.0 × 10−7–1.0 10−2 M) has low detection limit (7.4 10−8 M). potentiometric is independent pH solution in 1.9–5.1. proposed time (<15 s) good selectivity relative to variety other metal ions including common alkali, alkaline earth, heavy, transition ions. can be used for at least 60 days without any considerable divergence potentials. successfully applied an indicator titration 1.0 M 10−4 EDTA direct determination mineral water wastewater samples.