ANALYTICAL AND BIOCHEMICAL MEASUREMENTS WITH A NEW SOLID-MEMBRANE CALCIUM-SELECTIVE ELECTRODE

Evaluation of an immobilized matrix type, calcium-ion-selective membrane electrode shows several advantages over the earlier liquid membrane electrode. In particular, the electrode is shown to have a reduced selectivity for the hydrogen ion, resulting in a useful extension of the electrode's pH range into the acidic region. Selectivity for calcium over common interfering univalent and divalent cations is satisfactory for most practical measurements. The new electrode is successfully employed for direct potentiometry, potentiometric titrations, and the study of three calcium complexes of biological significance. © 1969, American Chemical Society. All rights reserved.