Potentiometric performance of a dioxime-type Schiff base as a silver-ion recognizable material

To examine the functionality as an Ag+ neutral carrier of a dioxime-type Sc hiff base easily obtained by coupling the dyad monoxime to the diamine, sev eral kinds of Schiff bases were synthesized using the diamine of which the different alkyl chain lengths, and Ag+ ion selectivities for the obtained S chiff bases were evaluated by potentiometry. Among the Schiff bases tested here, N,N ' -bis(2 ' -hydroxyimino-1 ' -phenyl-propylidene)-1,3-propanediam ine, PHO3, derived from alpha -Isonitrosopropiophenone and 1,3-Diaminopropa ne was found to be the most excellent Ag+ neutral carrier. That is, the PHO 3 - NPOE (plasticizer) - KTpClPB (anion excluder) system PVC membrane elect rode gave good results with a Nernstian response (59 mV decade(-1)) in acco rdance with the wide Ag+ activity change in the activity range 10(-6.3) M s imilar to 10(-1.1) M. The Ag+ ion selectivity with respect to K+ ion - log k(Ag,k)(pot) was 3.35 (fixed interference method, FIM). In addition, when t he practical performance, such as the response time, potential stability an d lifetime for the PHO3 - NPOE - KTpClPB system electrode was examined, the functionality of PHO3 derivative as the Ag+ neutral carrier was comparable to that of the conventional Ag+ neutral carrier.