Zr-MOF@PtNPs-Based High-Recognition Colorimetric Immunochromatographic Assay Strip for Synchronous and Highly Sensitive Detection of ZEN and FB

Fusarium toxins, as significant pollutants threatening global food security, have garnered increasing attention due to their mixed contamination issues. Among them, the co-contamination rate of ZEN and FB (Total Fumonisins) in grains reaches up to 37.6%, and both exhibit synergistic toxicity, are difficult to remove, and pose serious threats to animal and human health. Therefore, developing rapid and sensitive multi-target detection technologies is of great importance. However, traditional colloidal gold-based colorimetric ICA for multi-detection suffers from drawbacks such as signal overlap and insufficient sensitivity. In this study, we synthesized a signal probe Zr-MOF@PtNPs by leveraging the high molar extinction coefficient of PtNPs and the high specific surface area of Zr-MOFs. Zr-MOF stabilizes and disperses PtNPs, enabling them to exhibit excellent colorimetric performance with superior recognition under different light backgrounds, significantly enhancing the detection sensitivity and anti-background interference capability of traditional multi-detection colorimetric ICA. In this research, a dual immunochromatographic method using Zr-MOF@PtNPs as signal labels was established for the simultaneous detection of ZEN and FB in corn, which is simple to operate and achieves detection ranges of 0.15-5 ng/mL for ZEN and 0.6–10 ng/mL for FB, with LODs of 0.27 ng/mL and 0.21 ng/mL, respectively. This improves the detection sensitivity of multi-detection colorimetric immunochromatographic assay strips for synchronous detection of ZEN and FB, providing new methodological support for the simultaneous detection of multiple mycotoxins.