title: Critical study of and improvements in chromatographic methods for the analysis of type B trichothecenes.
abstract: Various analytical methods used in the analysis of type B trichothecenes (deoxynivalenol, nivalenol, 3- and 15-acetyldeoxynivalenol) in cereals were compared and optimised in this work. These methods use either GC-electron-capture detection (ECD) of trimethylsilyl, trifluoroacetyl and heptafluorobutyryl derivatives or HPLC with UV or photodiode array detection of analytes. A new HPLC procedure using fluorescence detection prior derivatisation with coumarin-3-carbonyl chloride has been also tested. Five extraction solvents and two solid-phase extraction cartridges (silica, Florisil) plus a especial clean-up column (MycoSep 225) were compared in order to obtain the best recovery of the mycotoxins with minimal presence of coextractives in the chromatograms. The chosen extraction solvent was a mixture of acetonitrile-water (84:16, v/v). The MycoSep 225 column was chosen as the best alternative for clean-up of grain samples. For GC-ECD analysis, derivatisation of analytes with heptafluorobutyric anhydride prior the final determination was chosen as the most suitable procedure. HPLC-photodiode array (at 221 nm) analysis was more suitable for determination of type B trichothecenes than HPLC of the fluorescent coumarin-3-carbonyl derivatives. Recoveries obtained in spiked corn, rice and wheat are reported. The utility of the proposed methodology was assayed in cereal cultures of various Fusarium strains.
authors.affiliation: Dpto. Microbiología, Facultad CC Biológicas, Universidad de Valencia, Burjasot, Spain. jose.j.mateo@uv.es
authors.forename: J J
authors.initials: JJ
authors.lastname: Mateo
authors.forename: A
authors.initials: A
authors.lastname: Llorens
authors.forename: R
authors.initials: R
authors.lastname: Mateo
authors.forename: M
authors.initials: M
authors.lastname: Jiménez
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002523:Edible Grain / Q000382:microbiology; D005670:Fusarium / Q000737:chemistry; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D014255:Trichothecenes / Q000032:analysis*
chemical_list: D014255:Trichothecenes; C043247:3-acetyldeoxynivalenol; C038405:nivalenol; C046760:15-acetyldeoxynivalenol; C007262:deoxynivalenol