Abstract
<title>Abstract</title> <p> Acrolein, classified as a Group 2A carcinogenic pollutant, was generated during the high-temperature processing of food. Traditional detection methods often face challenges in achieving on-site detection and rapid screening. This study presents carbon dot-coupled single-atom iron (CDs@Fe-SA) composite nanozymes, which exhibit high peroxidase-like activity and were synthesized through a green self-assembly strategy. The heterogeneous interface formed by carbon dots and the active center of the single-atom enzyme, Fe-N <sub> <italic>x</italic> </sub> , facilitates electron transfer and significantly enhances catalytic performance, evidenced by a Michaelis constant of 0.52 mM for H₂O₂. The research indicated that N-acetylcysteine markedly inhibited the enzyme-like activity of CDs@Fe-SA, resulting in the fading of the chromogenic catalytic product. Leveraging the specific Michael addition reaction between acrolein and N-acetylcysteine (NAC), the decolorization effect of NAC can be effectively mitigated, thereby establishing a novel colorimetric strategy for the detection of acrolein. The well plate method and a paper-based colorimetric method were subsequently developed to fulfill the requirements for high-throughput and on-site detection scenarios. Results indicate that the linear range of the well plate mode spans from 20 to 1000 μM, with a detection limit of 12.02 μM. The paper-based method enables high-precision on-site detection within the range of 0.3 to 2.3 mM. This approach is applicable for detecting acrolein in fried and baked foods, achieving a spiked recovery rate between 97.0% and 115.9%. The dual-mode sensing system established in this study effectively addresses the need for rapid on-site screening. Notably, the incorporation of small sample machine learning algorithms has significantly enhanced the quantitative accuracy of the paper-based method. This research offers novel technical support for food safety. </p>