Investigation of Schiff Bases Containing Acryloyl Moiety as Ionophore in Potentiometric Ion-Selective Sensors

In this study, all-solid-state chromium (III) selective potentiometric poly(vinylchloride) (PVC) membrane sensors were constructed by using the newly synthesized ionophores called (E)-4-((4–nitrophenylimino) methyl) phenyl acrylate (A1), (E)-4-((4-chlorophenylimino) methyl) phenyl acrylate (A2) and (E)-4-(4- hydroxybenzylideneimino) benzoic acid acrylate (A3). The most suitable membrane composition, which has the best potentiometric characteristics, was examined by using membrane cocktail coated electrodes containing the ionophores, o-nitrophenyloctyl ether (o-NPOE), bis(2-ethylhexyl) sebacate (DOS), dibutyl phthalate (DBP), dioctyl phthalate (DOP) and PVC. In addition, the effect of potassium tetrakis(4-chlorophenyl) borate (KTpClPB) and sodium tetraphenylborate (NaTPB) as ionic additives was investigated to determine optimum membrane composition. The optimum membrane composition was determined as 1.0 % (w/w) A2, 67.0 % (w/w) o-NPOE, and 32.0 % (w/w) PVC. On the condition of pH 3.50 the prepared electrode exhibited a linear response over the concentration range of 1.3×10-7−1.0×10-1 M chromium (III) ion solutions (R2=0.9938) with a sensitivity of 27.1 ± 0.8 mV/ decade, detection limit of 6.3×10-8 M and short response time of ≤10 s. The influences of some widely used cation species over electrode responses were studied. In order to investigate whether the proposed electrode could be used analytically, potentiometric determination of chromium (III) ion was carried out in real samples. The results were statistically compared with the Inductively Coupled PlasmaMass Spectrometry (ICP-MS) method.