A reliable method for the determination of T-2 toxin and HT-2 toxin in different cereals, including oats, as well as in cereal products was developed. After extraction with methanol/water (90/10, v/v) and dilution with a 4% NaCl solution, the toxins were purified with immunoaffinity columns, derivatized with 1-anthroylnitrile, separated by HPLC, and determined using fluorescence detection. Due to the unspecific derivatization reagents, validation parameters were matrix dependent: in the range 10-200 microg/kg, recovery rates of 74-120% with relative standard deviations between 0.5 and 20.3% were obtained. On average, the limit of quantitation was shown to be 8 microg/kg for each toxin. For naturally contaminated samples, comparable results were obtained when analysis was performed according to this method without derivatization as well as according to a method based on a SPE cleanup utilizing tandem mass spectrometric detection in both cases. Using aqueous acetonitrile as extractant resulted in incorrectly high toxin concentrations due to water absorption of dry samples and toxin accumulation in the organic phase in the subsequent phase separation of the extractant. Furthermore, when comparing the commercially available immunoaffinity columns for T-2 and HT-2 toxins, significant differences regarding capacity and cleanup performance were observed.

An easy, fast and reliable method based on a dispersive solid phase extraction (DSPE) cleanup for the determination of DON, T-2, HT-2, and ZEA is introduced. Using a consecutive extraction with water and acetonitrile followed by a forced phase separation (salting out), the cleanup is performed with primary-secondary amines (PSA) as bulk solid phase material. Furthermore, a rapid method without cleanup for fumonisin analysis is presented. HPLC with a triplequad MS and ESI source was used for the detection of all analytes. Since matrix effects always occur while performing mass spectrometry, experiments were done in order to quantify these effects. DON, T-2, HT-2, and ZEA show (in part highly) suppressed signals depending on matrix. Less effects for fumonisins-a slight suppression for FB1 and a slight enhancement for FB2-are observed. For compensation of these partly strong effects, dilution and standard addition as well as the use of isotope-labeled internal standards are performed and discussed. The validity of the methods is proven by comparison with reference methods as well as by cleanup of quality control samples. Furthermore, different method parameters of both methods (LOD, LOQ, recovery, linear range, etc.) are presented.

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