ARS | Publication request: DEVELOPMENT OF A DIPSTICK LATERAL FLOW ASSAY FOR THE DETECTION OF DEOXYNIVALENOL AND ZEARALENONE IN WHEAT

Submitted to: European Seminar in Fusarium Mycotoxins Taxonomy and Pathogenicity
Publication Type: Abstract Only
Publication Acceptance Date: June 26, 2006
Publication Date: September 19, 2006
Citation: De Saeger, S., Sibanda, L., Maragos, C.M., Verheijen, R., Velghe, G., Van Peteghem, C. 2006. Development of a dipstick lateral flow assay for the detection of deoxynivalenol and zearalenone in wheat [abstract]. European Seminar in Fusarium (EFS9) Mycotoxins Taxonomy and Pathogenicity. Book of Abstracts. p. 35.

Technical Abstract: A dipstick lateral flow test was developed for the detection of deoxynivalenol (DON) and zearalenone (ZEA) in wheat. DON and ZEA monoclonal antibodies (Mab)-gold conjugates were prepared by mixing 50 ml of 40 nm gold particles (G40; OD450~0.9) pH 8.5 suspension with 0.2 M K2CO3 and coated with 5 µg of Mab using the glycerol method. DON and ZEA assays consisted of a simple extraction procedure: 5 g of sample were extracted in 15 ml of extraction solution (50% methanol/3% aqueous NaHCO3). The extract (1 ml) was mixed with 600 µl of dilution solution (3% aqueous NaHCO3). The membrane was spotted with 2 µl cm-1 of undiluted anti-mouse antibodies defining the upper control line. For the lower test line 2 µl cm-1 ZEA or DON-bovine serum albumin conjugate (1:5 in 0.1% casein/PBS) was immobilized. After drying and blocking, the membranes were cut to 0.5 to 2.5 cm strips and sample and absorbent pads were fixed each on one side of the strip. To run the test, 600µl of diluted sample extract (containing 8.6µl 0.01% SDS + 1µl surfactant) were mixed with 10µl DON or ZEA Mab-gold conjugate. The strip was placed into the sample/conjugate mixture allowing the fluid to flow in an upwards direction. Results were observed within 7 min. Cut-off levels for DON and ZEA in fortified wheat samples were 200 and 100 µg kg-1 respectively. DON or ZEA concentrations lower than the cut-off level resulted in 2 red lines, while concentrations at or above the cut-off limit resulted in only 1 line.