Proposed Recommendations on Ion-Selective Electrode Determinations of the Substance Concentration of Sodium, Potassium and Ionized Calcium in Serum Plasma or Whole Blood

Ion-selective electrodes (ISEs) make possible the measurement of a wide range of analytes, which cover such diverse substances as ions, dissolved gases, enzymes etc. in serum, plasma or whole blood (1). The aims of this lecture are to outline some of the problems that have arisen with the introduction of sodium, potassium and calcium ISEs in clinical chemistry. In this context I want to discuss provisionally proposed recommendations which are prepared by a European Working Group on Ion Selective Electrodes (EWGISE)1 of the International Federation of Clinical Chemistry (IFCC) consisting of clinical chemists and manufacturers with a common interest in exchanging ideas and information on ISEs and trying to resolve some of the problems created by the increasing use of this new technology. The group started in 1982 and has held meetings in Oslo (1983), Oxford (1984), Helsinki (1985) and Graz (1986) in which European, American, Australian and Japanese invited scientists both from profession and industry participated.