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Updated: Jun 5, 2026

An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Single sensor for two metal ions: colorimetric recognition of Cu2+ and fluorescent recognition of Hg2+
Lijun Tang1, Fangfang Li, Minghui Liu
1College of Chemistry and Chemical Engineering, Liaoning Key Laboratory for the Synthesis and Application of Functional Compounds, Bohai University, Jinzhou, China. lijuntang@tom.com
Abstract:
The first novel rhodamine B based sensor, rhodamine B hydrazide methyl 5-formyl-1H-pyrrole-2-carboxylate Schiff base (2) capable of detecting both Cu(2+) and Hg(2+) using two different detection modes has been designed and synthesized. The metal ion induced optical changes of 2 were investigated in MeOH:H(2)O (3:1) HEPES buffered solution at pH 7.4. Sensor 2 exhibits selective colorimetric recognition of Cu(2+) and fluorogenic recognition of Hg(2+) with UV-vis and fluorescence spectroscopy, respectively. Moreover, both of the Cu(2+) and Hg(2+) recognition processes are proven to be hardly influenced by other coexisting metal ions.
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