Sensors : Construction and performance characteristics of new ion-selective electrodes for determination of ketotifen fumarate

Ion selective electrodes (ISEs) are electrochemical sensors that allow potentiometric determination of the activity of certain ions in the presence of other ions in the sample solution. Potentiometric sensors are essentially passive electrochemical devices, in which changes in the electromotive force (emf) are monitored under virtually zero current conditions. In so-called direct potentiometry, the emf is ideally a function of the activity of only one chosen sample-ion so that it can be selectively assessed in the presence of other ions. Achieving sufficient selectivity to measure one ion in the presence of others has long been the main focus of research in this field. This work has been carried out to present and characterize new plastic membrane, coated wire and chemically modified carbon paste electrodes for the determination of the antihistaminic drug, Ketotifen fumarate. The electrodes are based on individual and/or mixed ion-associates formed from the ion-associations of the drug cation with anions of phosphotungstate and tetraphenylborate. The electrodes were constructed and fully characterized.Each electrode was applied to the potentiometric determination of the drug cation