Potentiometric determination of potassium cations using a nickel(II) hexacyanoferrate-modified electrode

R J Mortimer; P J Barbeira; A F Sene; N R Stradiotto

doi:10.1016/s0039-9140(98)00373-7

Potentiometric determination of potassium cations using a nickel(II) hexacyanoferrate-modified electrode

Talanta. 1999 Jun 14;49(2):271-5. doi: 10.1016/s0039-9140(98)00373-7.

Authors

R J Mortimer¹, P J Barbeira, A F Sene, N R Stradiotto

Affiliation

¹ Department of Chemistry, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK.

PMID: 18967597
DOI: 10.1016/s0039-9140(98)00373-7

Abstract

Electroactive nickel(II) hexacyanoferrate (NiHCF) thin film modified electrodes are effective potentiometric sensors for the determination of potassium ions. The NiHCF films are deposited onto glassy carbon electrodes by repetitive potential cycling in K(3)Fe(CN)(6)/NaNO(3)/Ni(NO(3))(2) solution. The modified electrodes exhibit a linear response to potassium ions in the concentration range 1x10(-3) to 2.0 mol dm(-3), with a near-Nernstian slope (45-49 mV per decade) at 25 degrees C. In the determination of potassium ion in syrups used for treatment of potassium deficiency, the NiHCF-modified electrode gave comparable results to those obtained using flame emission spectrophotometry.