Colorimetric zearalenone assay based on the use of anaptamer and of gold nanoparticles withperoxidase-like activity.

Abstract

An aptamer based colorimetric assay is described for the determination of zearalenone (ZEN). It is based on the inhibition of the peroxidase-mimicking activity of gold nanoparticles (AuNPs) by the ZEN aptamer. However, in the presence of ZEN, the aptamer is bound by ZEN and can no longer inhibit the peroxidase-mimicking activity of AuNPs. The color change of solution is related to ZEN concentration and observed with bare eyes. Under optimal conditions, the absorbance (at 630nm) increases linearly in the ZEN concentration range of 10-250ng·mL-1, and the limit of detection is 10ng·mL-1. The specificity of the assay was verified by studying the effect of potential interferents. The recoveries from ZEN spiked corn and corn oil range from 92 to 110%, and the relative standard deviations are between 2.4 and 6.4%. The results are in good agreement with those obtained by an ELISA. Graphical abstract Schematic presentation of colorimetric assay for rapid and sensitive determination of zearalenone (ZEN) based on the inhibition of ZEN aptamer on the the peroxidase-like activity of gold nanoparticle (AuNPs).