Pickering Laboratories on February 25 announced that researchers at the Munich Technical University and Bavarian Health and Food Safety Authority have developed an innovative, comprehensive mycotoxin screening method based on the use of LCTech’s GPC ULTRA gel permeation chromatography instrument. Distributed by Pickering Laboratories in North America for sample cleanup prior to separation and detection, the new GPC instrument separates low weight mycotoxins from high molecular weight food constituents prior to high performance liquid chromatography (HPLC) separation and mass spectroscopy (MS) detection. The new method substantially lowers the cost of performing a comprehensive mycotoxin screen by detecting 31 mycotoxins in a single analysis run.
A proposed European Community regulation sets a maximum level of 1000ug/kg for fumonisins (FB1/FB2) in corn oil, making it more important than ever to develop a comprehensive mycotoxin screen. Development of a comprehensive screen is a demanding challenge because of the wide range of chemical and physical properties of the individual mycotoxins and the large number of naturally occurring food constituents that may be extracted along with the mycotoxins and interfere with separation and detection.
Traditional methods for detecting and quantifying low levels of mycotoxins are specific to individual mycotoxins, so it is time-consuming, difficult and expensive to carry out a comprehensive screen. Earlier GPC-based methods have been based on commonly-used polystyrene polymer beads, which are suitable for zeralenone (ZEA), ochratoxin A (OTA), aflatoxins and trichothecenes. However, this material does not provide sufficient selectivity to separate fumonisins (FB1/FB2) from the oil fraction.
C. Gottshalk and J. Bauer of Munich Technical University, J. Barthel and G. Engelhardt of the Bavarian Health and Food Safety Authority and U. Aulwurm of LCTech worked together to develop a method to detect 31 different mycotoxins, including ZEA, fumonisins, trichothecenes (types A, B and D), aflatoxins, ochratoxin A and other mycotoxins, from edible oils. The new method relies on the fact that mycotoxins fall into the 200 to 600 molecular weight range and thus can be separated using GPC from food constituents that have much higher molecular weights.
To develop this comprehensive screen, researchers used the LCTech’s GPC ULTRA automated sample cleanup and concentration instrument, which is distributed by Pickering Laboratories in Canada, Mexico, and the United States. They tried a range of different columns and found that the LCTech’s MykoClean column successfully separated all 31 analytes from the oil. The researchers studied influencing factors such as the eluent composition, pH, temperature and the column loading capacity. The recoveries obtained with the combined GPC-LC-MS/MS method range between 74 percent and 104 percent. The limits of quantification achieved with the new method comply with the maximum levels for analytes regulated by EC 1881/2006 regulations from December 19, 2006.
For additional detail, see the poster at http://www.pickeringlabs.com/pdf/080425-ua-Poster_30_Mykotoxin_Workshop1.pdf.