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Updated: Jun 28, 2026

Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition
Published on: February 5, 2022
Potentiometric flow injection determination of manganese(II) by using a hexacyanoferrate(III)-hexacyanoferrate(II)
Hiroki Ohura1, Yuko Ishibashi, Toshihiko Imato
1Department of Industrial Chemistry, Faculty of Engineering, Kyushu Sangyo University, Matsugadai, Higashi-ku, Fukuoka 813-8503, Japan.
Abstract:
A highly sensitive potentiometric flow injection analysis method for the determination of manganese(II), utilizing a redox reaction with hexacyanoferrate(III) in near neutral media containing ammonium citrate is described. The analytical method is based on the detection of the change in potential of a flow-through type redox electrode detector, resulting from the composition change of an [Fe(CN)(6)](3-)-[Fe(CN)(6)](4-) potential buffer solution. A linear relationship between the potential change (peak height) and the concentration of manganese(II) was found. Manganese(II) in a wide concentration range from 10(-4) to 10(-7) M could be determined by appropriately altering the concentration of the potential buffer from 10(-3) to 10(-5) M. The lower detection limit of manganese(II) was determined to be 1x10(-7) M. The sampling rate and relative standard deviation were 20 h(-1) and 1.9% (n=8) for 6x10(-6) M manganese(II), respectively. The proposed method was successfully applied to the determination of manganese(II) in actual soil samples obtained from tea fields. Analytical results obtained by the proposed method were in good agreement with those obtained by an atomic absorption spectrophotometric method.
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