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Updated: Jun 8, 2026

Accumulation and Analysis of Cuprous Ions in a Copper Sulfate Plating Solution
Published on: March 20, 2019
Naked-eye determination of oxalate anion in aqueous solution with copper ion and pyrocatechol violet
Jing Su1, Yuan-Qiang Sun, Fang-Jun Huo
1Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan, 030006, China.
Abstract:
A novel strategy for the determination of oxalate anions was successfully established using a copper ion and pyrocatechol violet (PV) ensemble. The sensor ensemble can discriminate oxalate over other common anions including F(-), Cl(-), I(-), Br(-), HPO(4)(2-), PO(4)(3-), AcO(-), CO(3)(2-), SO(4)(2-), ClO(4)(-), P(2)O(7)(4-), S(2-) (deposited by Ag(+)), CN(-) (shielded by Fe(3+)) and can detect oxalate at low microgram levels in quasi-physiological aqueous solutions. The detection of the oxalate anion gives rise to a rapid observable visual color change from blue to yellow.
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