title: Potentiometric performance of silver ion-selective electrodes based on tridentate Schiff base derivatives.
abstract: To examine the directivity for improving the silver ion discrimination ability of a Schiff base, three kinds of tridentate ligands were synthesized and compared with the similar quadridentate ligand as the silver ionophore. Among the Schiff base derivatives tested, 3-(2-pyridylethylimino)-2-butanoneoxime, having one oxime and a pyridine substituent, was found to be the best ionophore for a silver-ion electrode. The electrode based on this derivative exhibited good silver-ion selectivity, -log Kpot(Ag+,K+) = 3.8, comparable to that of a quadridentate Schiff base, N,N'-bis(2'-hydroxyimino-1'-phenylpropyleden)-1,3-propanediamine, reported previously, except for a pseudo Nernstian response (35.6 mV decade(-1)) with a wide silver-ion activity change in the activity change from 5.0 x 10(-7) to 7.9 x 10(-2) mol dm(-3).
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1, Omiya, Asahi, Osaka 535-8585, Japan. ueda@k7.chem.oit.ac.jp
authors.forename: Masato
authors.initials: M
authors.lastname: Ueda
authors.forename: Takahiro
authors.initials: T
authors.lastname: Saito
authors.forename: Keiichi
authors.initials: K
authors.lastname: Fujimori
authors.forename: Takayo
authors.initials: T
authors.lastname: Moriuchi
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Shibutani