Abstract
Chromium(III) selective membrane sensors based on Schiff bases as chelating ionophores were presented. The sensor exhibited Nernstian response in the concentration range 8.9 10 super(-8) to 1.0 10 super(-1) M Cr super(3+) with limit of detection 5.6 10 super(-8) M. The selectivity behavior of the proposed electrode revealed a considerable improvement as compared to the best previously poly(vinylchloride) (PVC)-membrane electrode for chromium(III) ion. The sensor had found to work satisfactorily in partially non-aqueous media up to 20% content of methanol, ethanol and acetonitrile and could be used for a period of 3 months. The proposed electrode was used as an indicator electrode in potentiometric titration of chromium ion with EDTA and in direct determination in different water and food samples.