SUPERCRITICAL-FLUID EXTRACTION OF MYCOTOXINS FROM FEEDS WITH ANALYSISBY LC UV AND LC/MS/

The use of supercritical fluid extraction with supercritical carbon di oxide and a matrix modifier is described for the isolation of three tr ichothecene mycotoxins from yellow corn meal and rolled oats. The quan tity of supercritical carbon dioxide used in each extraction was 30 mL which contained 5% methanol used as a modifier. The pressure was main tained at 550 atm., and the temperature of the extraction chamber was set at 60 degrees. Recovery of the target analytes from cereal and cor n feed by supercritical fluid extraction (SFE) varied from 85 to 95 % depending on the target compound. The mycotoxins, deoxynivalenol (DON) , deacetoxyscirpenol (DAS) and T-2 toxin (T-2) were monitored in the S FE extracts by high performance liquid chromatography with UV-detectio n (HPLC-UV) or ion spray mass spectrometry under full-scan, selected i on monitoring (SIM) and selected reaction monitoring (SRM) modes. Ther e are significant restrictions in the HPLC-UV detection limits for T-2 and DAS, in particular, due to their low UV absorbance. With HPLC-UV and also HPLC-MS in the full-scan mode of acquisition the considerable interference from co-eluting fat-soluble compounds precluded detectio n of these compounds in feed extracts. In the SIM and SRM LC/MS modes the target analytes could be readily detected at the 250 ppb level in the cereal SFE matrix extracts.