New Procedure for Fumonisins B₁ and B₂ in Corn and Corn Products by Ion Pair Chromatography with <i>o</i>-Phthaldialdehyde Postcolumn Derivatization and Fluorometric Detection

Abstract

Fumonisins are a group of naturally occurring mycotoxins produced by Fusarium moniliforme. An analytical method for fumonisins B1 and B2 in corn and related foods has been developed that utilizes ion pair chromatography with a postcolumn reaction technique. Samples were prepared and purified by tandem solid phase extraction columns (SAX and C18). The fumonisins were derivatized with o-phthaldialdehyde and N-acetyl-l-cysteine in an in-line reaction coil. Ion pair liquid chromatography with fluorescence detection is used for the separation and detection. Absolute recoveries of fumonisins ranged from 54 to 110% at 0.04 and 0.08 μg/g. The detection limit of this method is 20 ng. This procedure is relatively simple and provides a screening method for fumonisins in corn and related foods. Keywords: Determination; fumonisin; solid phase extraction; ion pair chromatography; o-phthaldialdehyde; postcolumn reaction; fluorometric