Membrane drotaverine-selective electrodes based on tetraphenylborate derivatives: Electrochemical, adsorption, and transport properties and analytical application

The potentiometric response of ion-selective electrodes (ISEs) based on different lipophilic derivatives of tetraphenylborate to drotaverine hydrochloride was studied. The composition of a polymeric membrane was optimized to obtain the best electroanalytical properties of ISEs. The transport properties of selective membranes, the permeability and the flow of ions through the interface, were studied. Linear correlations between the solubility of ionophoric membrane components, membrane transport, and electroanalytical properties were revealed. The kinetic studies of ion-exchange adsorption showed that two limiting stages of transfer, namely, diffusion through the boundary layer and diffusion throug the membrane phase, occurred. Procedures for the potentiometric determination of drotaverine hydrochloride in pharmaceutical forms were proposed.