Analysis of fumonisins in corn-based food by liquid chromatography with fluorescence and mass spectrometry detectors

The presented procedure involves an extraction with methanol-water, centrifugation and cleanup with immunoaffinity columns. A comparison study between fluorescence detector, mass spectrometry, and tandem mass spectrometry with a triple quadrupole (QqQ) analyzer using an electrospray ionisation interface for the determination of fumonisin B-1 and B-2 in corn-based products has been performed. Limits of quantification obtained by the three detectors were lower than the maximum levels established by European Commission. Liquid chromatography coupled to tandem mass spectrometry provides higher sensitivity (12 mu g kg(-1) for fumonisins B-1 and B-2) when compared to mass spectrometry (40 mu g kg(-1) for both fumonisins). and fluorescence detection (20 mu g kg(-1) for fumonisin B-1 and 15 mu g kg(-1) for 132), and also showed to be more precise. At 150 and 250 mu g kg(-1) spiking levels, the recovery rates for fumonisin B, and 132 in corn products varied from 79% to 102%, with a relative standard deviation ranging from 9% to 17%. A critical assessment including advantages and drawbacks of each technique is presented. A total of 41 organic and non-organic corn-based food samples from Valencia markets were analyzed. Seven samples were contaminated with levels ranging from 68 mu g kg(-1) to 922 mu g kg(-1) of fumonisin B, and 42 mu g kg(-1) to 640 mu g kg(-1) of fumonisin B-2. Only one sample exceeded the maximum level for the sum of fumonisin B-1 and B-2, proposed for corn products in a recent EU regulation. The contamination frequency of organic corn samples (40%) was higher than non-organic ones (3.7%), and contained higher levels of fumonisin B-1 and B-2. (C) 2008 Elsevier Ltd. All rights reserved.