title: All-solid-state calcium solvent polymeric membrane electrode for low-level concentration measurements.
abstract: An all-solid-state calcium-selective electrode with a plastic membrane phase containing a calcium ionophore ETH-1001 placed on poly(3-methylthiophene) ion-to-electron transducting layer functionalized to bind calcium cations has been constructed. The obtained potentiometric sensors were characterized with a calibration line of slope close to Nernstian within the activity from 10(-5) to 0.1 M. For Ca2+ activity lower than 10(-5) M, super-Nernstian behavior was observed. The super-Nernstian response that is observed for electrodes with an internal solution strongly binding primary ions was in this case attributed to incorporation of calcium ions in the modified solid-contact phase. With this arrangement, the evaluation of selectivity coefficients much closer to those that depend on the properties of the ion-selective membrane itself was possible.
authors.affiliation: University of Warsaw, Department of Chemistry, Pasteura 1, 02-093 Warsaw, Poland. agatam@chem.uw.edu.pl
authors.forename: Agata
authors.initials: A
authors.lastname: Michalska
authors.forename: Anna
authors.initials: A
authors.lastname: Konopka
authors.forename: Magdalena
authors.initials: M
authors.lastname: Maj-Zurawska