Dependence of analytical parameters of ion-selective electrodes on the membrane solvents used in the construction of membranes

Abstract

The aim of this study was analysis of the suitability of available membrane solvents and their application to obtain liquid membrane ion-selective electrodes that are sensitive to diazepam or fluoxetine. Sensitive and reasonably selective poly(vinyl chloride) membrane electrodes are based on using water insoluble ion-pair of diazepam – [tetrakis(3,5bis-(trifluoromethyl)phenyl]borate or fluoxetine – [tetrakis(4-fluorophenyl)]borate as electroactive material. As membrane solvents for construction of membranes there were used 2-nitrophenyloctyl ether, bis(2-ethylhexyl) sebacate, 1-isopropyl-4-nitrobenzene, bis (1-buthylpentyl) adipate, tris(2-ethylhexyl) phosphate. Evaluation of analytical parameters of the obtained electrodes, their selectivity and evaluation of analytical parameters for membranes subjected to a process of "accelerated aging" in a climate chamber at 60 °C and humidity of 70 % without the VIS and UV light, were developed. There was carried out an analysis of the suitability of the electrodes, which will show the best stability and reproducibility of the analytical parameters for the determination of substances in respect of which exhibit selectivity. The determination was developed using potentiometric titration method.