Boosting peroxidase-like activity of Fe/Mn-N-C dual-single-atom nanozyme for colorimetric assay of total antioxidant capacity

Abstract

Total antioxidant capacity (TAC) quantification is pivotal for biomedical diagnostics and food quality control. Herein, we developed a smartphone-integrated colorimetric platform leveraging a Fe-Mn dual-single-atom nanozyme (Fe/Mn-N-C) with enhanced peroxidase-like activity. Density functional theory calculations revealed that the unique diatomic synergy reduced the energy barrier during the catalytic process, thus endowing Fe/Mn-N-C with superior peroxidase-like activity. The inhibition mechanism of different types of antioxidants on the color reaction was investigated. The system quantified AA via antioxidant-induced suppression of oxTMB formation and applied successfully to the TAC detection of several fruit juices and commercial beverages. This work provided a new perspective for designing advanced single-atom nanozyme and developed a low-cost and easy-to operate TAC detection strategy with good sensitivity and specificity.

Keywords

Single-atom nanozyme / Peroxidase-like / Colorimetric analysis / TAC / Smartphone

Declaration of Competing Interest

The authors declare that they have no competing financial interests or personal relationships that may have influenced the work reported in this study.

CRediT authorship contribution statement

Bingsong Yan: Writing - original draft, Methodology, Data curation. Yuanjie Zhang: Investigation, Formal analysis. Yizhong Lu: Supervision, Conceptualization. Zongming Liu: Project administration, Funding acquisition. Jinkai Li: Writing - review & editing.

Acknowledgements

We appreciate the financial support from the "New Universities 20" Foundation of Jinan (Grant No 2021GXRCO99, T202204).

Supplementary materials

Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.chphma.2025.09.001.

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