MEMBRANE OF IONOSELECTIVE ELECTRODE TO DETERMINE CALCIUM IONS

摘要

FIELD: physics.;SUBSTANCE: invention relates to the field of ionometry, in particular to the development of ion-selective electrodes with membranes based on polymer supramolecular systems. Membrane of the ion-selective electrode for the determination of calcium ions contains a polymer matrix, a plasticizer, a lipophilic additive and ionophore, in which polyvinyl chloride is used as a polymer matrix, and o-nitrophenyloctyl ether is used as a plasticizer, while as the ionophore is used bidentate phosphorus-containing podand tetratolyl-m-xylene diphosphine, and as a lipophilic additive tetrakis(4-fluorophenyl)potassium borate with the ratios of membrane components defined according to the invention. Invention allows to improve detection limit of calcium ions up to pCa²⁺=6.1 in aqueous solutions, and also increase the selectivity of determination in the presence of cations of alkaline and alkaline-earth elements, including biogenic, which allows the use of the developed electrodes for the analysis of biological objects (whole blood, serum, urine, et cetera) and in scientific research.;EFFECT: invention can be used for direct potentiometric determination of the activity of calcium ions in aqueous solutions: natural, waste waters, as well as biological fluids.;1 cl, 1 dwg, 2 tbl