Conducting polymer-based ion-selective electrodes

Single-piece, conducting polymer-based, potentiometric sensors with enhanced cationic sensitivity were obtained by doping a polypyrrole with metal-complexing, multivalent anions. Sulphosalycilic acid, Tiron, Eriochrome Black T and Kalces have been used as doping ions. Predominant sensitivity for copper was observed for the first two dopants, whereas for the two remaining ones, induced response for magnesium and calcium was found, respectively. Interestingly, in all sensors studied the metal-binding properties of the specific ligands known from polar solvents were retained. Hence, the specific reagents can be deliberately utilized for the construction of conducting polymer-based ion-selective sensors.