A Quick Assay for the Quantitation of Deoxynivalenol in Grain Samples by Liquid Chromatography with UV Detection.

A quick and effective extraction of deoxynivalenol (DON) in food samples is described. The samples were extracted using 80% acetonitrile-water solution, followed by a second extraction using an 80% methanol-water solution. The extract was then subjected to an immunoaffinity column (IAC) cleanup. Quantification of isolated analyte was obtained by LC with UV detection at 220 nm. LC-UV parameters were optimized with a C18 LC column resulting in a 6 min run time. Certified reference materials (CRMs) of three different matrixes at three different levels were analyzed. Wheat, barley, and corn samples containing 0.5, 1.0, and 1.9 mg/kg, respectively, were analyzed. Recoveries from all CRM samples were calculated using an external standard curve (Figure 1) and ranged from 80 to 102%. Confirmation of DON in the sample extracts was accomplished using LC/MS. This method provides a rapid, specific, and robust assay for the analysis of DON with an uncertainty measurement of 12.2% and method detention limit of less than 0.125 mg/kg. Other methods that do not use an IAC produce dirty extracts that sometimes require washing the chromatographic column after each sample injection. The method presented here does not require washing the column, which leads to faster LC analysis time/sample.