Partial blocking of ion transport at the interface of an ion-selective liquid membrane electrode by neutral surfactants. Experiments and computer simulation

Lipophilic neutral surfactants of the sugar alkyl ester type are experimentally observed to substantially increase the ion transfer impedance between an aqueous solution and ion-selective electrode membranes made from plasticized PVC with neutral carrier. The magnitude of the effect depends considerably on the molecular structure and on the concentration of the surfactant. Statistical thermodynamic simulation of the experimental system agrees qualitatively with the experimental observations.