Highly efficient detection of deoxynivalenol and zearalenone in the aqueous environment based on nanoenzyme-mediated lateral flow immunoassay combined with smartphone

Deoxynivalenol (DON) and zearalenone (ZEN) pose a serious threat to human health, and have been frequently detected in the aqueous environment. To protect consumers from the harm of mycotoxins, a nanozyme-mediated multiplexed lateral flow immunoassay (LFIA) integrated with a smartphone was developed for rapid, highly sensitive and simultaneous quantitative detection of DON and ZEN in the aqueous environment. Highly efficient peroxidase mimicking core-shell Au@Pt nanozymes were synthesized by one-pot method, and then used as signal amplification to highly improve sensitivity of the detection, while a smartphone-based quantitative detection device could rapidly quantify results to improve the detection efficiency of the LIFA for on-site detection. After optimization, the detection time of the assay was 10 min, and the detection limits of the LIFA for DON/ZEN were 0.24/0.04 ng/mL, which were improved 416 and 150 folds compared to the conventional gold nanoparticles (GNPs)-based LFIA. Moreover, there was no obvious cross-reaction with other related mycotoxins, indicating that LFIA had a high specificity. The average recoveries of DON and ZEN from corn, wheat and three water samples were obtained from 94.3 % to 107.9 % with relative standard deviations of 0.2-7.6 %. Furthermore, the accuracy and reliability of the LIFA were evaluated with three spiked water samples, and the results presented good correlations with analytic results from the enzyme-linked immunosorbent assay (R2 =0.988 for DON, and 0.983 for ZEN). The results indicate the proposed LIFA was potentially a rapid, on-site simultaneous and highly sensitive method for DON and ZEN detection in the aqueous environment.

Automated summary

A nanozyme-mediated multiplexed lateral flow immunoassay (LFIA) integrated with a smartphone was developed for rapid, highly sensitive and simultaneous quantitative detection of deoxynivalenol (DON) and zearalenone (ZEN) in the aqueous environment. Highly efficient peroxidase mimicking core-shell Au@Pt nanozymes were used as signal amplification to improve the detection sensitivity, while a smartphone-based quantitative detection device could rapidly quantify results to enhance the detection efficiency. The LFIA showed high specificity, improved detection limits, and good correlation with the results from the enzyme-linked immunosorbent assay (ELISA).