A Novel Molecularly Imprinted Polymer On CDSE/ZNS Quantum Dots For Highly Selective Optosensing Of Mycotoxin Zearalenone In Cereal Samples

Zearalenone (ZON), a mycotoxin, is mainly produced by Fusarium fungi, and contaminates cereal crops such as corn, barley, sorghum, wheat and oats. ZON causes reproductive problems, infertility in farm animals, and causes severe liver and kidney problems due to its estrogenic activities. It also has cytotoxicity, genotoxicity, immune toxicity and carcinogenicity, directly or indirectly endangers human health. Thus, it is necessary to establish a high selective method for ZON detection.A novel molecularly imprinted optosensing material (MIOM) based on ionic liquid (IL)-stabilized CdSe/ZnS quantum dots (QDs) was prepared for highly selective and sensitive recognition of ZON.Since ZON is expensive and highly toxic, cyclodo-decanyl-2,4-dihydroxybenzoate (CDHB) which is ZON analogue was chosen as the template. MIOM was synthesized via a bulk polymerization process with methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylic acid (EGDMA) as cross-linker and2,2-azobisisobutyronitrile (AIBN) as initiator and combining with IL-stabilized CdSe/ZnS QDs. MIOM was characterized by scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR) and adsorption experiment. The results showed that after binding ZON, the fluorescence intensity of MIOM quenched. Under optimal conditions, the relative fluorescence (FL) intensity of MIOM decreased linearly with the increasing concentration of ZON in the range of0.003-3.12μmol L-1with a detection limit of0.64μg L-1.To evaluate the usefulness of the developed method, MIOM was applied to detect ZON in corn, rice and wheat flour, and atthree concentration levels50,100and500ng g"1, the recoveries for three samples were94.2%-98.7%(RSD<4.7%),84.4%-106.0%(RSD<3.9%),93.1%-107.65%(RSD<7.4%), respectively. It proves that the developed method based on MIOM for detection of ZON in cereals is feasible. Furthermore, to verify the validity of the developed method, immunoaffinity column combining high performance liquid chromatography and fluorescence detection was used to detect ZON recoveries of above samples. The results were65.9%-68.2%(RSD<9.3%),64.4%-79.3%(RSD<8.9%),69.4%-75.9%(RSD<5.2%), respectively, which proves the efficiency of the method based on MIOM for detection of ZON in cereals.