A Molecularly Imprinted Polymer Based on Fe3O4@Au Nanoparticles for Detection of Aflatoxin B1 in Food Samples

Based on molecular imprinting and nanotechnology, a molecular imprinted polymer (MIP) coupled with Fe3O4-Au nanocomposite adsorbent has been successfully developed for rapid quantification of aflatoxin B1 in foodstuff. The characterization of the prepared Fe3O4-Au and Fe3O4-Au-MIP was studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). The limit of detection (LOD) and limit of quantification (LOQ) were estimated to be 6.12 and 18.6 mu g L-1, respectively. The adsorption capacity was 8.975 mg g(-1) which revealed that the synthesized magnetic MIP (MMIP) presented high selective recognition property to AFB1. The selectivity adsorption experiments indicated that compared with three different competetive Aflatoxins, MMIP showed excellent affinity to AFB1. It was found that the adsorption capacity of MMIP for AFB1 remained essentially the same after 6 adsorption-desorption cycle which shows the acceptable repeatability and reusability of the MMIP. The proposed method was successfully applied to the estimation of AFB1 in non-alcoholic beer and barley samples with good recoveries (94.47-97.31 %). Also, the relative standard deviation (RSD %) values were lower than 3.7 %. The selectivity, stability and reproducibility of the proposed method were acceptable. The results revealed that Fe3O4-Au@MIP could be used as an efficient and reusable adsorbent for AFB1 in food samples. This study provides a simple, inexpensive, fast, accurate and environmentally-friendly technique instead of expensive and time-consuming procedures for determining AFB1 in food matrices.