0

Fluoride-selective Polymeric Membrane Electrodes Based on Zr(IV)- And Al(III)-salen Ionophores of Various Structures

Łukasz Górski, Alexey Matusevich, Paweł Parzuchowski, Iwona Łuciuk, Elzbieta Malinowska

Anal Chim Acta. 2010 Apr 14;665(1):39-46.

PMID: 20381688

Abstract:

Al(III)- and Zr(IV)-salophens of novel structures were tested as anion-selective ionophores. It was shown that these compounds are highly selective to fluoride and give selectivity greatly deviating from classical Hofmeister pattern, when doped into the polymeric membrane of ion-selective electrode (ISE). The following selectivity sequence has been recorded for both ionophores: F(-) > ClO(4)(-) > SCN(-) > NO(3)(-) approximately Br(-) approximately Cl(-). The results of potentiometric and spectrophotometric measurements allow to conclude that the nature and structure of salophen ligands influence stability of ISE working parameters. An increase in salophen ligands lipophilicity results in prolongation of the ISE lifetime, most likely due to slower ionophore decomposition caused by the hydrolysis of imine bonds in salophen structure. Ion-selective electrodes (ISEs) with the most successful Al(III)-salophen exhibited a stable, fast and near-Nernstian fluoride response and a functional lifetime near 3 weeks and selectivity coefficients with log K(F(-), Y(-))(pot) as follows: -2.8 (Y(-)=Br(-)), -2.7 (Cl(-)), -2.8 (NO(3)(-)), -1.5 (SCN(-)), -1.3 (ClO(4)(-)), which is better than for other ones based on Zr(IV)- and Al(III)-salophens and salens described to date.

Chemicals Related in the Paper:

Catalog Number Product Name Structure CAS Number Price
AP12150468 Zirconium ionophore I Zirconium ionophore I 12150-46-8 Price
qrcode