Cobalt Single-Atom Nanozyme-Enabled Multimodal Lateral Flow Immunoassay for On-Site Ultrasensitive Detection of Tetracycline Residues in Agri-Food Products

Rui Huang ¹, Tibebu Tsegaye Zigale ¹, Hui Meng ¹

⁰School of the Environment and Safety Engineering, School of the Emergency Management, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China.

Journal of Agricultural and Food Chemistry +

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June 17, 2025

View abstract on PubMed

Summary

A novel cobalt single-atom nanozyme (CoSAN) significantly enhances lateral flow immunoassays (LFIA) for detecting tetracycline (TC) residues. This advancement offers a highly sensitive, cost-effective, and field-deployable solution for ensuring food safety.

Area Of Science

Analytical Chemistry
Materials Science
Food Safety

Background

Tetracycline (TC) residues in food pose significant health risks, demanding sensitive and portable detection methods.
Conventional gold nanoparticle-based lateral flow immunoassays (AuNP-LFIA) lack the sensitivity and cost-effectiveness required for widespread field application.
Development of advanced nanomaterials is crucial for improving the performance of rapid diagnostic tools.

Purpose Of The Study

To develop a highly sensitive and cost-effective nanozyme for detecting tetracycline (TC) residues in agricultural products.
To integrate the novel nanozyme into a multimodal lateral flow immunoassay (LFIA) platform for enhanced detection capabilities.
To evaluate the performance of the CoSAN-based LFIA for on-site food safety screening.

Main Methods

Synthesis of a cobalt single-atom nanozyme (CoSAN) with a Co-N5 coordination structure via a template-pyrolysis strategy.
Characterization of CoSAN's peroxidase-like activity and reactive oxygen species generation (•OH, •O2-, 1O2).
Construction of a multimodal LFIA platform incorporating CoSAN for colorimetric, catalytic amplification, and chemiluminescent detection of TC.

Main Results

The CoSAN exhibited excellent peroxidase-like activity, significantly boosting colorimetric and chemiluminescent signals.
The CoSAN-integrated LFIA achieved detection limits of 0.091, 0.062, and 0.056 ng/mL, demonstrating 43- to 70-fold sensitivity improvements over AuNP-LFIA.
Analysis of real milk and honey samples confirmed no tetracycline residues exceeding regulatory limits.

Conclusions

Cobalt single-atom nanozymes offer a superior alternative to gold nanoparticles for enhancing LFIA sensitivity and performance.
The developed multimodal LFIA platform provides a robust, sensitive, and cost-effective tool for on-site food contaminant screening.
This approach significantly advances the capability for rapid and reliable detection of tetracycline residues, contributing to improved food safety.

Keywords:

lateral flow nanozyme peroxidase-like tetracycline