Ultrasensitive monitoring strategy of PCR-like levels for zearalenone contamination based DNA barcode.

Background: The ultrasensitive monitoring strategy of zearalenone (ZEN) is essential and desirable for food safety and human health. In the present study, a coupling of gold nanoparticles-DNA barcode and direct competitive immunoassay-based real-time polymerase chain reaction signal amplification (RT-IPCR) for ZEN close to the sensitivity of PCR-like levels is described and evaluated.

Results: The RT-IPCR benefited from the use of a DNA barcode and RT-PCR detection strategy, thus resulting in ultrasensitive and simple detection for ZEN. Under the optimal RT-IPCR, the linear range of detection was from 0.5 to 1000 pg mL-1 and the limit of detection was 0.5 pg mL-1 , which was 400-fold lower than the enzyme-linked immunosorbent assay. The detection procedure was simplified and the detection time was shortened. The specificity, accuracy and precision of the RT-IPCR confirmed a high performance. ZEN-positive contamination levels were from 0.056 to 152.12 ng g-1 by the RT-IPCR, which was demonstrated to be highly reliable by liquid chromatography-tandem mass spectrometry.

Conclusions: The proposed RT-IPCR could be used as an alternative for detecting ZEN with satisfactory ultrasensitivity, simplicity, low cost and high-throughput. The present study could provide a strategy for the ultrasensitive detection of the small molecule with a simple and practical approach, which has significant appeal and application prospects.