Flow injection amperometry as an alternative to potentiometry for solid contact ion-selective membrane-based electrodes.

In this work we propose a flow injection amperometry at constant potential as a perspective alternative to classical potentiometry for solid contact ion-selective electrodes (SC-ISEs). The amperometric readout mode eliminates the problem of background drift and potential instability ? common limitations of potentiometry for SC-ISEs. The selectivity in flowinjection and constant flow amperometric modes is similar to the potentiometric one. Moreover, flow injection amperometry in comparison to potentiometry for ion-selective electrodes provides a shorter response time, within 15?30 s, by two orders of magnitude decreased detection limit and 5-6 fold increased signal-to-noise ratio. The proposed approach is an attractive readout mode that opens new horizons for the improvement of performance characteristics of solid contact ISEs. ? 2021 Elsevier Ltd. All rights reserved. In this work we propose a flow injection amperometry at constant potential as a perspective alternative to classical potentiometry for solid contact ion-selective electrodes (SC-ISEs). The amperometric readout mode eliminates the problem of background drift and potential instability ? common limitations of potentiometry for SC-ISEs. The selectivity in flowinjection and constant flow amperometric modes is similar to the potentiometric one. Moreover, flow injection amperometry in comparison to potentiometry for ion-selective electrodes provides a shorter response time, within 15?30 s, by two orders of magnitude decreased detection limit and 5-6 fold increased signal-to-noise ratio. The proposed approach is an attractive readout mode that opens new horizons for the improvement of performance characteristics of solid contact ISEs.

Automated summary

This study proposes flow injection amperometry as a potential alternative to classical potentiometry for solid contact ion-selective electrodes, providing faster response time and higher signal-to-noise ratio while eliminating background drift and potential instability.