Development of Highly Sensitive Time-Resolved Fluorescence Immunosensor for Detection of Aflatoxingenetic Fungi And Revealing Early Risk of Aflatoxin in Food and Environment

Aflatoxin is a group of highly toxic and carcinogenic mycotoxins, produced by aflatoxingenetic fungi which widely exists in our living environment and food, thus threatening human health. Based on the previous discovery of a biomarker and the development of its nanobody and polyclonal antibody, here we report a highly sensitive time-resolved fluorescence immunosensor for detection of aflatoxingenetic fungi and revealing early risk of aflatoxin production in environment and food. Additionally, a strain of A. flavus with high producing aflatoxin capacity was used to make the standard reference for aflatoxingenetic fungi. Under the optimized conditions, the sensor’s sensitivity reached 0.1 μg/mL, each assay was finished within 15 min, and the spiked recoveries of reference in peanuts were 77.02%~91.61%. And then, two important application cases were successfully demonstrated to identify the abundance of aflatoxingenetic fungi in peanut rhizosphere soil and market peanuts. The results indicated that aflatoxingenetic fungi could be detected even a few days before aflatoxin contamination. As a conclusion, it provides a novel strip sensor for detection of aflatoxingenetic fungi and revealing early risk of aflatoxin production in environment and food, which infers a new and important use of immunosensor, that is, early warning for biotoxin