Maryam Zakery, Ali A. Ensafi , and Behzad Rezaei

Abstract—A novel molecularly  imprinted fluorescent sen sor (MIFS) based on glutathione-modified CdTe quantum dots (QDs) was fabricated to detect and determine difeno conazole (DFZ) in agricultural products. Initially, glutathione modified CdTe QDs were synthesized via the refluxing method.  The MIFS was then synthesized by fixing a molecularly imprinted  polymer layer on the surface of QDs through a sol–gel process. Transmission electron microscopy, fluorescence spectrometry, dynamic light scattering analysis, X-ray diffraction analysis, and  Fourier transform infrared spectroscopy were finally employed to
 characterize the QDs and the fabricated sensor. In this MIFS, the selectivity of molecular imprinting techniques and the sensitivity of QDs were combined to fabricate for the first time a simple and inexpensive sensor of high selectivity and sensitivity for the detection of DFZ. Fluorescence quenching was observed to occur so that the fluorescence intensity of the MIFS decreases linearly with increasing DFZ concentration in the range of 2.5–124.5 ng/mL with a detection limit of 0.5 ng/mL. Finally, the
 MIFS was employed to measure DFZ in agricultural products Good recoveries ranging from 90.1% to 112.2% were obtained, indicating the successful and highly accurate determination of DFZ in agricultural products by the MIFS