A sensitive colorimetric and ratiometric chemosensor for trivalent metal cations
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Updated: Apr 17, 2026

Quantification of Metal Leaching in Immobilized Metal Affinity Chromatography
Published on: January 17, 2020
1School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, People's Republic of China.
Abstract:
A novel hydroxyethyl piperazine functionalized cyanine derivative was designed and synthesized. It presents selective colorimetric as well as ratiometric absorption responses to trivalent metal cations (Cr(3+), Fe(3+) and Al(3+)) over a variety of divalent and monovalent metal cations in 3:7 ethanol-water solution. Detection limits of this method for Cr(3+), Fe(3+) and Al(3+) were 3.99 μM, 4.30 μM and 1.85 μM, respectively. The recognition mechanism was attributed to the protonation of the organic probe, which blocked the photoinduced electron transfer (PET) process. In addition, the sensor was also successfully applied to the determination of Cr(3+) in prepared samples.
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