Phage displayed mimotope peptide-based immunosensor for green and ultrasensitive detection of mycotoxin deoxynivalenol.

Immunoassays play an important role in the monitoring and detection of mycotoxins in food. However, mycotoxin conjugates in the immunoassay system synthesized with toxic mycotoxin as raw material has seriously harmed the environment and human health during and after the performance. In this work, using mycotoxin deoxynivalenol (DON) as a model happen, a selected DON mimotope (phage-displayed peptide) that specifically binds to anti-DON antibody was served as a mimetic competing antigen in electrochemical immunosensor for ultrasensitive and green detection of DON. Under the optimized conditions, the mimotope peptide-based electrochemical immunosensor showed a dynamic range of 0.1-10,000 pg/ml and the limit detection (LOD) of 0.07 pg/ml. In addition, the accuracy and reproducibility of the established electrochemical immunosensor were evaluated by testing cross-reactivity and spiking DON negative samples. The result showed that mimotope peptide-based immunosensor has negligible cross-reactivity with other mycotoxins, and the average recovery of corn and wheat sample was 90.4%-118% and 101.3%-111%, respectively. Furthermore, the novel concept might provide potential applications to a general method for the immunosensor of various toxic small molecules.