Dipstick enzyme immunoassay to detect Fusarium T-2 toxin in wheat.
A dipstick enzyme immunoassay for the rapid detection of Fusarium T-2 toxin in wheat was developed. An Immunodyne ABC membrane was precoated with rabbit anti-mouse immunoglobulins. After the strips were immersed in a solution of monoclonal anti-T-2 toxin antibodies, a direct competitive enzyme immunoassay was performed. This assay included the incubation of the antibody-coated dipsticks in a mixture of sample and T-2 toxin-horseradish peroxidase conjugate. Afterwards, the strips were placed in a chromogen-containing substrate solution (H202-3,3',5,5'-tetramethylbenzidine) for color reaction. The dot color intensity of toxin-positive dipsticks was visually distinguishable from that of the negative control. A portable colorimeter was used to confirm and quantify the visual observations. With coated strips, the tests could be performed in 45 min. The visual detection limit for T-2 toxin in buffer solution was 0.25 ng/ml. Artificially infected wheat samples were extracted with 80% methanol-water. A dilution of the raw extract of 1:8 was sufficient to avoid matrix effects. It was possible to make visually a clear distinction between the negative control and a wheat extract spiked with 12 ng/g.
De Saeger
S
S
Laboratory of Food Analysis, Faculty of Pharmaceutical Sciences, University of Ghent, Belgium. Sarah.DeSaeger@rug.ac.be
Van Peteghem
C
C
D000818:Animals; D000911:Antibodies, Monoclonal; D005069:Evaluation Studies as Topic; D005670:Fusarium / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification; D007124:Immunoenzyme Techniques; D008567:Membranes, Artificial; D051379:Mice; D011817:Rabbits; D013605:T-2 Toxin / Q000032:analysis* / Q000276:immunology; D014908:Triticum / Q000737:chemistry* / Q000382:microbiology*
D000911:Antibodies, Monoclonal; D008567:Membranes, Artificial; D013605:T-2 Toxin