2 The Bio-Medical and Related Roles of Ion-Selective Membrane Electrodes

Abstract

Publisher Summary Ion-selective electrodes are now commercially available for about twenty common anions and cations. Their development has coincided with the demand for convenient methods of ion determinations in the biomedical field, stimulated by the successes of the fluoride electrode in determining trace fluoride in water fluoridation and dental health programmes. Ion-selective electrodes may be classified according to membrane material into glass, homogeneous and heterogeneous solid-state, liquid ion-exchanger, carrier complex, semi-conducting organic charge-transfer complex and ionradical salt, PVC matrix membrane with liquid ion-exchanger or other sensor, and electroactive hydrophobised graphite. Interest in the use of ion-selective electrodes in the biomedical field is a natural consequence of the electrolyte composition of bulk body and cell fluids, a proportion of which is in the ionized form. On the wider biomedical front, application of ion-selective electrodes takes in mineralized tissues, dental materials, enzyme reactions, and pharmaceutical products and drug metabolism.