In this study, a newion-selective electrode for Ba2+ is described, illustrating 3-deoxy-D-erythro-hexos-2-ulose bis (thiosemicarbazone) (DHUT) in a poly(vinylchloride) (PVC) membranewith 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 comparisonwith 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 11with a lower detection limit of 5.6×10−7 M. Moreover, the sensors displayed the Nernstian slope of 29.6±0.5 mVper decade, having a fast response timewithin 15 s over the entire concentration range. It could also be used for at least 2 monthswith no potential divergence. As a result, the developed sensorwas successfully applied to the direct bariumion determination in solutions, rock samples and as an indicator electrode in the Ba2+ ion potentiometric titration with EDTA.

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