Rapid screening method for deoxynivalenol in agricultural commodities by fluorescent minicolumn.
A rapid screening procedure based on the selective adsorption of deoxynivalenol (DON) from extracts of wheat and corn has been developed. DON is extracted from the sample with acetonitrile-water (85 + 15) and partially purified on a preparative minicolumn. Solvent is evaporated and the residue is dissolved in toluene-acetone (95 + 5) and chromatographed on a novel detector minicolumn which selectively adsorbs DON. A blue fluorescence is produced when the column is heated 5 min at 100 degrees C. The procedure is capable of detecting DON at greater than or equal to 500 ng/g. Forty-three wheat samples, contaminated with DON at 60-6300 ng/g, were assayed by gas chromatography-mass spectroscopy (GC-MS) of the heptafluorobutyryl derivative of DON and by the selective adsorption procedure. Comparison of results showed 91% agreement between data from the 2 methods. Selective adsorption assays were positive for all samples that were greater than or equal to 500 ng/g by GC-MS (no false negatives) and were negative for 85% of samples less than 500 ng/g (4/27 false positives). These four samples contained greater than 200 ng/g by GC-MS. Samples of wheat (64), corn (23), soybeans (8), and sorghum (6) were extracted and extracts were assayed by thin-layer chromatography and the selective adsorption procedure. Selective adsorption assays agreed with TLC results.
Gordon
W C
WC
Rialdon Diagnostics, College Station, TX 77841.
Gordon
L J
LJ
D002855:Chromatography, Thin Layer; D005504:Food Analysis; D008401:Gas Chromatography-Mass Spectrometry; D007202:Indicators and Reagents; D012717:Sesquiterpenes / Q000032:analysis*; D013025:Glycine max / Q000032:analysis; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D014255:Trichothecenes / Q000032:analysis*; D014908:Triticum / Q000032:analysis; D003313:Zea mays / Q000032:analysis
D007202:Indicators and Reagents; D012717:Sesquiterpenes; D014255:Trichothecenes; C007262:deoxynivalenol