UiO-66-NH2 MOF-based fluorescent aptasensor for detection of zearalenone in cereals

The presence of zearalenone (ZEN) toxin in agricultural foods and animal feed ingredients has become a global public health concern due to its pathogenic effects. As a result, the development of novel, highly accurate, rapid, and reliable analytical methods for ZEN detection is essential for ensuring food safety. In the present work, a highly sensitive aptasensor for ZEN was developed using UiO-66-NH2 metal-organic framework (MOF) and graphene oxide (GO). A highly fluorescent UiO-66-NH2 MOF, conjugated with ZEN aptamer, was employed as a fluorescent signal probe (lambda ex/em = 330/430 nm) while GO functioned as a quencher in the assay. In the presence of ZEN, the fluorescence intensity of the MOF increased significantly as the aptamer-UiO-66-NH2 showed its affinity toward ZEN, releasing the GO. Under the optimal experimental conditions, the assay displayed excellent specificity, repeatability, and linearity over the ZEN concentration range of 0.01-100 ng/mL, yielding a low detection limit of 5 pg/mL. In addition, the developed sensor also demonstrated satisfactory performance with recoveries from 85 to 114% in the spiked samples of wheat and corn flour. In general, the developed sensing strategy provides a new approach for the rapid, inexpensive, and sensitive fluorescent detection of ZEN in food matrices.