Highly sensitive fluorescence sensing of zearalenone using a novel aptasensor based on upconverting nanoparticles.

A facile strategy was successfully developed for the detection of zearalenone (ZEN). In this assay, highly fluorescent upconversion nanoparticles were synthesized and conjugated with the complementary oligonucleotide of ZEN aptamer for use as signal probes. Magnetic nanoparticles immobilized with the ZEN aptamer were assigned as capture probes. The results exhibited that the linear correlation between the decreased luminescence intensity of the signal and the concentration of ZEN was very strong (R=0.9957) in the range of 0.05-100μg/L. In addition, the limit of detection of the proposed method (0.126μg/kg for corn and 0.007μg/L for beer) was significantly lower than the existing methods. Furthermore, the reliability of the competitive immunoassay format was validated by comparing the results determined in real food samples to those obtained from a commercially available method. Overall, the novel aptasensor have showed great potential for rapid and accurate ZEN determination.