Selective extraction and enrichment of aflatoxins from food samples by mesoporous silica FDU-12 supported aflatoxins imprinted polymers based on surface molecularly imprinting technique.

In this work, a highly selective surface molecular imprinted polymers (FDU-12@MIPs) were prepared using structural analogues of aflatoxins as the template molecule and mesoporous silica FDU-12 as the carrier. The resulting polymers were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and attenuated total reflection Fourier transform infrared spectrometer. A highly ordered mesoporous nanostructure was observed in the fabricated polymer. Results showed that the adsorption capacity of FDU-12@MIPs for aflatoxins were higher than that of non-imprinted mesoporous silica polymer (FDU-12@NIPs). FDU-12@MIPs were successfully used as a solid-phase extraction sorbent coupled with HPLC for aflatoxin G2, G1, B2 and B1 determination in food samples. Under optimized conditions, recoveries from the spiked cereals were found to be 82.6%-116.7%, with relative standard deviations ranging from 2.73 to 4.21. The detection limits of aflatoxin G2, G1, B2 and B1 were estimated to be 0.05 μg kg, 0.06 μg kg, 0.06 μg kg and 0.05 μg kg, respectively. Limits of quantifications were estimated to be 0.15 μg kg, 0.2 μg kg, 0.2 μg kgand 0.15 μg kg, respectively. The developed method exhibited a favorable linear response toward aflatoxin G2, G1, B2 and B1 in the range of 0.1 μg kg-50 μg kg, R is 0.9992-0.9996. These results indicated that FDU-12@MIPs could be used as an efficient adsorbent of solid phase extraction for enrichment of aflatoxins in real samples.