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

Abstract

A Fe 3? ion-selective membrane sensor was fabricated from polyvinyl chloride (PVC) matrix membrane containing bis-bidentate Schiff base (BBS) as a neutral carrier, sodium tetraphenyl borate (NaTPB) as anionic excluder, and o-nitrophenyloctyl ether (NPOE) as a plasticizing solvent mediator. The effects of the membrane composition, pH, and additive anionic influence on the response properties were investigated. The best performance was obtained with a membrane containing 32% PVC, 62.5% NPOE, 3% BBS, and 2.5% NaTPB. The electrode shows a Nernstian behavior (slope of 19.3 ± 0.6) over a very wide iron ion concentration range (1.0 9 10 -7 -1.0 9 10 -2 M) and has a low detection limit (7.4 9 10 -8 M). The potentiometric response of the sensor is independent of pH of the solution in the pH range 1.9-5.1. The proposed sensor has a very low response time (\15 s) and a good selectivity relative to a wide variety of other metal ions including common alkali, alkaline earth, heavy, and transition metal ions. The electrode can be used for at least 60 days without any considerable divergence in potentials. The proposed sensor was successfully applied as an indicator electrode for the potentiometric titration of 1.0 9 10 -2 M Fe 3? ions with a 1.0 9 10 -4 M EDTA and the direct determination of Fe 3? in mineral water and wastewater samples.

Comparison of polysiloxane films substituted by undecenyl-cyclam and by naphthyl-cyclam for the design of ISFET devices sensitive to Fe3+ ions

“…The design of sensitive ISFET chemical sensors is the subject of active research in the fields of supramolecular chemistry. The aim is to select complexing agents that allow specific recognition of iron(III) species [22][23][24], and insurface immobilization processes to produce an ISFET surface that will be durably sensitized by strong immobilization by means of chemical grafting [25].…”

A lutetium pvc membrane sensor based on (2-oxo-1,2-diphenylethylidene)-n-phenylhydrazinecarbothioamide

“…[22][23][24][25][26][27][28][29][30][31][32][33][34] The tube, now having a layer of the membrane on the tip were next kept at room temperature for 12 h before being filled with an internal filling solution (1.0×10 -3 mol L -1 of the target ion) and conditioned for 24 h in a 1.0×10 -2 mol L -1 solution of the target ion. To do this, the tips of the tubes were dipped into the mixture for a short time.…”

Fabrication of a Praseodymium(III) PVC-Membrane Sensor Based on N′1,N′2-Bis(2-oxo-1,2-diphenylethylidene) ethanedihydrazide

“…In this work, the potentiometric selectivity coefficients of the Pr(III) sensor were evaluated by the matched potential method (MPM) (Umezawa, Umezawa, and Sato 1985;Zamani, Ganjali, Norouzi, and Adib 2007;Zamani, Ganjali, Norouzi, Tajarodi, and Hanifehpour 2007;Abedi, Zamani, Ganjali, and Norouzi 2008;Abedi and Zamani 2008;Zamani 2008;Zamani, Ganjali, and Salavati-Niasari 2008). The resulting selectivity coefficients values are given in Table 2.…”