The new methods of determination of Mg2+, Ca2+, Na+ and K+ ions in erythrocytes by ion selective electrodes

Intracellular ionized magnesium, sodium and potassium were determined using a clinical potentiometric analyzer with ion-selective electrodes. The results did not differ significantly compared with other methods (magnetic resonance spectroscopy (NMR), atomic absorption spectrometry (AAS), flame emission spectrometry (FES), inductively coupled mass spectrometry (ICP-MS), zero-point titration (ZPT)). An appropriate composition of the ion-selective membrane for intracellular calcium determination was found. The ionized magnesium determination in erythrocytes was successfully used in medical analysis of dialyzed and critically ill postoperative patients. (c) 2005 Elsevier B.V. All rights reserved.