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Updated: Jun 28, 2026

An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Dual-wavelength spectrophotometric determination of cadmium with cadion
1Department of Applied Chemistry, Muroran Institute of Technology, Mizumoto-cho 27-1, Muroran-shi, Hokkaido, Japan.
Abstract:
Cadmium has been determined by dual-wavelength spectrophotometry with cadion, p-nitrobenzenediazoaminobenzene-p-azobenzene, and a non-ionic surfactant, Triton X-100. Cadion and its cadmium chelate are dissolved in a micellar solution of the surfactant. The absorbance difference at the wavelength of maximum absorption of the cadmium chelate (477 nm) and that of cadion (566 nm) is measured. A combination of triethanolamine, iminodiacetate and citrate is very effective for masking other ions. Cadmium in zinc metal can be determined without prior separation.
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