Related Experiment Video
Updated: Aug 17, 2026

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
A convenient colorimetric assay for Cr(VI) detection based on homogeneous Cu(II)-GMP system with oxidoreductase-like
Qian-Yu Zhou1, Yi Song1, Xu-Xia Yan1
1School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China.
Abstract:
Hexavalent chromium (Cr(VI)) is an environmental pollutant and recognized as a human carcinogen. Therefore, it is necessary to develop a simple and sensitive detection technique for Cr(VI). Herein, it is found that Cu2+ interacts with guanosine 5'-monophosphate (GMP) to form a homogeneous Cu(II)-GMP complex (Cu2+·GMP) that efficiently displays the oxidoreductase-like catalytic activity. Cu2+·GMP can catalyze the oxidation between Cr(VI) and substrate 3,3',5,5'- tetramethylbenzidine (TMB), resulting in color change recognized by the naked eyes. Base on this, a convenient colorimetric assay for Cr(VI) detection was developed. The detection limit (3σ/s) of this sensor for Cr(VI) was 23 nM with a linear range of 0.1-25 μM. Moreover, the proposed assay was successfully applied to detect Cr(VI) in different environmental water samples with satisfactory recoveries. Our method is simple, efficient, rapid and cost-effective for Cr(VI) detection without the need for complicated material preparation or special separation, which shows great potential in environmental monitoring.
More Related Videos
Related Concept Videos
Qualitative Analysis
For instance, group IV...
Redox Titration: Other Oxidizing and Reducing Agents
Complexometric Titration: Overview
Effects of EDTA on End-Point Detection Methods
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...
Precipitation Titration: Endpoint Detection Methods
In the Volhard method, a standard excess of AgNO3 is first added to the...

