Submitted to: Journal of Food Additives & Contaminants
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/10/2007
Publication Date: 2/10/2008
Citation: Maragos, C.M., Appell, M.D., Lippolis, V., Visconti, A., Catucci, L., Pascale, M. 2008. The use of cyclodextrins as modifiers of fluorescence in the detection of mycotoxins. Journal of Food Additives & Contaminants. 25(2):164-171. Interpretive Summary: Some of the well known mycotoxins, such as the aflatoxins, zearalenone, and ochratoxins, are fluorescent, which can help in their detection. Recently we have investigated mechanisms for enhancing this fluorescence using cyclodextrins. By enhancing the fluorescence of the mycotoxins and their derivatives, we hope to further increase the sensitivity of assays for their detection. This report summarizes the literature on the use of cyclodextrins to enhance the fluorescence of mycotoxins in analytical applications, and extends the concept to a mycotoxin (T-2 toxin) that can be rendered fluorescent.
Technical Abstract: Cyclodextrins (CDs), cyclic oligosaccharides composed of amylose subunits, are known to interact with mycotoxins. The interactions may be useful to analytical chemists by altering the properties of the mycotoxin of interest, namely the chromatographic properties, electrophoretic properties, fluorescence, or absorption of these fungal metabolites. Practical applications of these effects have been the incorporation of CDs into high performance liquid chromatography (HPLC) and capillary electrophoresis (CE) methods for mycotoxin detection. Specific mycotoxins include those with a native fluorescence such as the aflatoxins, ochratoxin A (OTA), and zearalenone (ZEN), as well as those that can be rendered fluorescent through derivatization, such as T-2 toxin. The literature describing the applications of cyclodextrins in mycotoxin analysis are reviewed, and an attempt to extend the use of CDs to the detection of labeled T-2 toxin is presented. Twenty CDs were evaluated for their ability to enhance the fluorescence emission of T-2 toxin derivatized with pyrene-1-carbonyl cyanide (T2-Pyr). This evaluation revealed that heptakis (2,6-di-O-methyl)-Beta-cyclodextrin (DIMEB) in particular enhanced T2-Pyr fluorescence. DIMEB was used as a buffer modifier in a CE-laser induced fluorescence (CE-LIF) method for detecting T-2 in maize. Because of the effects that certain cyclodextrins have, especially under aqueous conditions, they may make useful additives for a variety of mycotoxin analytical methods.