Determination of Fumonisin B1 and B2 in Corn Using Matrix-Phase Dispersion Coupled to High Performance Liquid Chromatography

Abstract

A simple, rapid and reproducible analytical method for the determination of fumonisin B₁ (FB₁) and fumonisin B₂ (FB₂) in corn samples by matrix solid-phase dispersion procedure coupled to high performance liquid chromatography (HPLC) with photo-diode array detector (DAD). Several dispersants, eluents and ratios were tested during the optimization of the process in order to obtain the best results. Finally, samples were blended with C₁₈ and the mycotoxins were extracted with 10 mL of 10 mM formic acid in methanol. Analyses were performed by HPLC-DAD. The mobile phase was a mixture of a 77 % methanol and 23 % 0.1 M NaH₂PO₄ (pH 3.2) solution at 1 mL min^-1. The wavelength of detection was 335 nm. The recoveries of the extraction process ranged from 71.0 to 119.7 % with relative standard deviation lower than 15.7 % in all cases, when samples were fortified at three different concentration levels. Limits of detection and quantification were 0.05, 1 and 0.2, 2.0 μg g^-1, respectively. Application of the method to the analysis of 13 samples including, corn kernel, flour, corn starch, popcorn, purchased in local supermarkets in Guangzhou city, China, revealed FB₁ and FB₂ levels.