Application of magnetic solid phase extraction for separation and determination of aflatoxins B1 and B2 in cereal products by high performance liquid chromatography-fluorescence detection

A simple and sensitive method based on the magnetic solid phase extraction with modified magnetic nanoparticles followed by high performance liquid chromatography with fluorescence detection has been developed for extraction and determination of aflatoxins B-1 (AFB(1)) and B-2 (AFB(2)) in cereal products. Magnetic nanoparticle coated with 3-(trimethoxysilyl)-1-propanthiol (TMSPT) and modified with 2-amino-5-mercapto-1,3,4-thiadiazole (AMT) was used as an antibody-free adsorbent. Under the optimal conditions, the calibration curves for AFB(1) and AFB(2) were linear in the ranges of 0.2-15 mu g L-1 and 0.04-3 mu g L-1, respectively. Detection limit was 0.041 mu g L-1 for AFB(1) and 0.013 mu g L-1 for AFB(2). The proposed method was successfully applied to the determination of AFB(1) and AFB(2) in spiked corn and rice samples with an average recovery of 93.5%. The results demonstrated that the developed method is simple, rapid, inexpensive, accurate and remarkably free from interference effects. (C) 2014 Elsevier B.V. All rights reserved.