Polymer Membrane Ion-Selective Electrodes–What are the Limits?

This article reviews recent advances in the field of potentiometric solvent polymeric membrane electrodes. These sensors have found widespread applications in a variety of fields, especially in the area of clinical diagnostics. Emphasis is given on the discussion of the theoretical and practical limits of ionophore-based ion-selective electrodes, with a special focus on electrode sensitivities, characterization of selectivities and dramatic improvements in detection limits. Advances in ionophore design and in the underlying model assumptions are also discussed. It is shown that a multitude of exciting new research possibilities have recently emerged in this well—established field.