Ionophore-free potentiometric sensor for the determination of calcium(II) ions

Year 2025, Volume: 2 Issue: 2, 18 - 26, 29.12.2025

Onur Cem Altunoluk , İsa Mert Eşki

Abstract

In this study, ionophore-free polymer membrane potentiometric sensors were produced, and then these newly produced sensors were found to exhibit selective behavior towards calcium(II) ions. The developed calcium(II)-selective potentiometric sensor had a low detection limit of 6.64×10−6 mol L−1 over a wide concentration range of 1.0×10−1–1.0×10−5 mol L−1. The proposed calcium(II)-selective sensor also had a fast response time (<8 s), good reproducibility, low-cost fabrication, and wide pH working range (3.0–10.0). Finally, the fabricated ionophore-free sensors were shown to be able to detect calcium(II) ions in environmental water samples with very high recovery rates, pointing to their applicability in the analyses of real samples.

Keywords

calcium (II) , ion-selective electrodes , sensor , potentiometry , ionophore-free

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