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Abstract: According to a solution study which showed a selective complexation between N,N′-bis(methylsalicylidene)-2-aminobenzylamine (MSAB) and gadolinium ions, MSAB was used as a sensing element in construction of a gadolinium(III) ion selective electrode. Acetophenon (AP) was used as solvent mediator and sodium tetraphenyl borate (NaTPB) as an anion excluder. The electrode showed a good selectivity towards Gd(III) ions over a wide variety of cations tested. The constructed sensor displayed a Nernstian behavior (19.7±0.3mV/decade) in the concentration range of 1.0×10−6 to 1.0×10−2 molL−1 with detection limit of 5.0×10−7 molL−1 and a short response time (<10s). The working pH range of the electrode was 3.5–10.1 and lifetime of the sensor was at least 10weeks. Analysis of certified reference materials confirmed the accuracy of the proposed sensor. The electrode was successfully applied as an indicator electrode in gadolinium titration with EDTA. [Copyright &y& Elsevier]

Abstract: Conductometric study in acetonitrile solution shows the selectivity of PCQ toward europium ion. Therefore, a new europium PVC membrane electrode was prepared based on N-pyridine-2-carboxamido-8-aminoquinoline (PCQ) as an ion carrier. The electrode has a wide concentration range from 1.0×10−2 and 1.0×10−6 molL−1, Nernstian slope of 19.8±0.3mV per decade and a detection limit of 6.4×10−7 molL−1. The potentiometric response is pH independent in the range of 2.4–7.4. The proposed sensor has a relatively fast response time less than 10s and it can be used for at least 2months without any considerable divergence in its potentials. The proposed electrode revealed good selectivity toward europium ion in comparison with variety of other metal ions. The practical utility of the electrodes has been demonstrated by their use as indicator electrodes in the potentiometric titration of Eu3+ ions with EDTA and for determination of Eu3+ ion concentration in mixtures of two and three different ions. [Copyright &y& Elsevier]

Abstract: A new selective Nd(III) sensor has been made by using N,N′-bis(quinoline-2-carboxamido)-4,5-dimethylbenzene (H2L4) as a suitable ionophore. The sensor exhibits Nernstian response to Nd(III) ions in the concentration range of 5.0×10−6 to 1.0×10−2 M. It displays a Nernstian slope of 19.5±0.4mV/decade in the pH range of 2.9–9.2. The proposed sensor also exhibits a fast response time of

Abstract: Solution study showed N,N′-bis(5-nitrosalicylidene)-2-aminobenzylamin (L) trends toward Tb3+ ion. Then, it was used as a suitable ionophore in construction of terbium ion selective electrode. The electrode with composition of 30% PVC, 65% solvent mediator (NB), 3% ionophore (L) and 2% anionic additive (NaTPB) shows the best potentiometric response characteristics. It displays a Nernstian behavior (20.1mVdecade−1) over the concentration range 1.0×10−6 to 1.0×10−2 molL−1. The detection limit of the electrode is 6.3×10−7 molL−1. It has a very short response time (~10s) and a useful working pH range of 2.6–9.4 for at least 2months. The proposed membrane sensor shows excellent discriminating ability towards Tb3+ ions with regard to several alkali, alkaline earth, transition and heavy metal ions. To investigate the analytical applicability of the sensor, it was successfully applied to the determination of terbium in certified reference material. [ABSTRACT FROM AUTHOR]

Abstract: A new Pr3+ poly vinyl chloride PVC membrane sensor based on a membrane containing 3% N,N′-bis(4-hydroxysalicylidene)-1-3-phenylenediamine (HSPDA) as an ionophore, 2% sodium tetraphenyl borate (NaTPB) as an anionic additive, 65% benzyl acetate (BA) as solvent mediator and 30% poly(vinyl chloride) was prepared. This sensor responds to praseodymium ion in a wide linear dynamic range of 1.0×10−6 to 1.0×10−2 molL−1 with Nernstian slope of 19.8±0.4mV per decade and a detection limit of 5.7×10−7 molL−1 in pH range of 3.1 to 9.8. It has a fast response time of ~5s in the whole concentration range, and can be used for at least 2months without any considerable divergences in the potentials. The proposed sensor displays an excellent selectivity for Pr3+ ions with respect to a large number of alkali, alkaline earth, transition and heavy metal ions. The developed sensor was successfully applied as an indicator electrode in Pr3+ ion potentiometric titration with EDTA, and in direct determination of fluoride ion in two mouth wash samples. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a new ion-selective electrode for Ba2+ is described, illustrating 3-deoxy-d-erythro-hexos-2-ulose bis (thiosemicarbazone) (DHUT) in a poly(vinylchloride) (PVC) membrane with benzyl acetate (BA) as a plasticizer and sodium tetraphenyl borate (NaTPB) as an anionic additive. This sensor presented very good selectivity and sensitivity towards the Ba2+ ions over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The electrode revealed a great improvement in the selectivity coefficients for the Ba2+ ions in comparison with the formerly reported Ba2+ sensors. The proposed electrode exhibited a significantly enhanced response towards the Ba2+ ions across the concentration range of 1.0×10−6–1.0×10−2 M for the pH variation from 2.6 to 11 with a lower detection limit of 5.6×10−7 M. Moreover, the sensors displayed the Nernstian slope of 29.6±0.5mV per decade, having a fast response time within 15s over the entire concentration range. It could also be used for at least 2months with no potential divergence. As a result, the developed sensor was successfully applied to the direct barium ion determination in solutions, rock samples and as an indicator electrode in the Ba2+ ion potentiometric titration with EDTA. [Copyright &y& Elsevier]

Abstract: The construction, performance characteristics, and application of a novel iron(III) membrane sensor based on a new bis-benzilthiocarbohydrazide (BBTC) are reported in this paper. The sensor is prepared by incorporating of BBTC, nitrobenzene (NB), and sodium tetraphenyl borate (NaTPB) into a plasticized poly(vinyl chloride) membrane. The electrode reveals a Nernstian behavior over a wide iron ion concentration range (1.0×10−2–1.0×10−7 mol L−1), and relatively low detection limit (8.6×10−8 mol L−1). The potentiometric response is independent on the pH of the solution in the range of 1.6–4.3. The electrode shows a very short response time (<10 s). The proposed electrode can be used for at least nine weeks without any considerable divergence in potentials. It exhibits very good selectivity relative to a wide variety of alkali, alkaline earth, transition and heavy metal ions. In fact, the selectivity of the proposed sensor shows great improvements compared to the previously reported electrodes for the iron ion. Also, the sensors accuracy was investigated in two ways: (i) with the potentiometric titration of a Fe(III) solution with EDTA and (ii) with the Fe(III) monitoring in river and wastewater samples. [Copyright &y& Elsevier]