Solid-contact ion-selective electrodes (SC-ISEs) are traditionally employed as potentiometric sensors, where the ion activity is related to the zero-current potential of the sensor vs. the ref. electrode. In this communication, an alternative ion-to-electron transduction principle for SC-ISEs is introduced. The suggested signal transduction principle resembles "const.-potential coulometry" utilizing the redox capacitance of the internal solid contact in order to convert changes in ion concn. (activity) into elec. current and charge. This short communication provides proof-of-concept for the suggested signal transduction method for SC-ISEs utilizing poly(3,4-ethylenedioxythiphene) (PEDOT) as the solid contact that was coated with a cation-sensitive polymeric membrane.