Determination of Aflatoxin B in Grains by Aptamer Affinity Column Enrichment and Purification Coupled with High Performance Liquid Chromatography Detection.

Aflatoxin B (AFB) is a highly teratogenic and carcinogenic secondary metabolite produced by . It is commonly detected in agricultural products such as cereals, peanuts, corn, and feed. Grains have a complex composition. These complex components severely interfere with the effective extraction and separation of AFB, and also cause problems such as matrix interference and instrument damage, thus posing a great challenge in the accurate analysis of AFB. In this study, an aptamer affinity column for AFB analysis (AFB-AAC) was prepared for the enrichment and purification of AFB from grain samples. AFB-AAC with an AFB-specific aptamer as the recognition element exhibited high affinity and specificity for AFB. Grain samples were enriched and purified by AFB-AAC, and subsequently analyzed by high performance liquid chromatography with post-column photochemical derivatization-fluorescence detection (HPLC-PCD-FLD). The average recoveries of AFB ranged from 88.7% to 99.1%, with relative standard deviations (RSDs) of 1.4-5.6% ( = 3) at the spiked levels of 5.0-20.0 μg kg. The limit of detection (LOD) for AFB (0.02 μg kg) was much below the maximum residue limits (MRLs) for AFB. This novel method can be applied to the determination of AFB residues in peanut, corn, and rice.