One stone two birds: smartphone-assisted colorimetric sensing system based on copper peroxide for iron(II) and tannic
Ting Wu1, Yuting Mei1, Xiulan Liu1
1School of Chemistry and Chemical Engineering, Nanchang University, Nanchang 330031, China. Zhengxiangjuan@ncu.edu.cn.
Abstract:
Copper peroxide (CuO2), known for its self-decomposition to generate H2O2, has been widely used in medical and antibacterial applications. In sensing systems, it is often combined with other materials to enhance performance. Herein, we report a dual-analyte colorimetric sensing platform based solely on CuO2. This system utilizes the self-decomposition of CuO2 to produce H2O2, which reacts with Fe2+ to amplify the Fenton reaction (Fe2+-H2O2), generating free radicals for Fe2+ detection. Meanwhile, tannic acid (TA) inhibits the Fenton reaction-generated free radicals, leading to suppressed TMB oxidation and enabling TA detection. This platform provides a simple, rapid, and cost-effective method for highly sensitive detection of Fe2+ and TA, with wide linear ranges of 0.1-100 μM and 10-100 μM, respectively. It was successfully applied to the analysis of various food samples. Furthermore, a portable smartphone-based approach using CuO2 was developed for on-site detection of Fe2+ (20-1000 μM) and TA (1-500 μM), integrating visual and digital analysis.
Related Concept Videos
01:18Effects 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...
00:39Complexometric Titration: Overview