Characterization, standardization and experiences with KONE ISE for Mg2+.

The principles of a fully automated potentiometric determination of ionized magnesium in human blood serum are presented. By incorporating a magnesium selective electrode, into a commercially available six channel electrolyte analyzer (Microlyte 6, KONE Instruments, Finland), determination of the biologically-active, ionized fraction of magnesium has been made possible. In this paper, the analytical performance of the measurement system is presented and determination of ionized magnesium in real patient samples is discussed with special attention to the significance of this new parameter.