EFS12- Book of abstracts - Contact

SESSION 2: SECONDARY METABOLITES – BIOCHEMISTRY,
BIOSYNTHESIS, FEED AND FOOD SAFETY
P36 - Comparison of Veratox® for T-2/HT-2 ELISA test
with GC-MS and LC-MS methods
S. Rämö 1 , P. Parikka 1 , A. Asola, 2 M. Jestoi 2
1 MTT Agrifood Research Finland, 31600 Jokioinen, Finland and 2 Finnish Food Safety authority Evira,
00790 Helsinki, Finland
E-mail: sari.ramo@mtt.fi
Neogen Veratox® for T-2/HT-2 toxin is ELISA test which promises 100 % cross
reaction for both toxins. The usefulness of the test was studied in MTT during
2011-2012. The possible matrix interferences were tested for wheat, barley and
oats, which were analyzed with a GC-MS reference method: Wheat did not show
any matrix interference. However, the need for matrix calibration for barley and
oats was observed. T-2 and HT-2 toxin free barley and oats samples were spiked
with toxin levels of 25 ppb to 250 ppb. Matrix interference was clear for barley,
whereas for oats the test’s calibration could be used.
T-2 and HT-2 toxins are a more considerable problem in oats than other grains in
Finland. 20 oats samples, which were analyzed with LC-MS in 2011, were chosen
for ELISA analysis. The ELISA tests were done during four days in August 2012.
The standards and samples were transferred to wells according to the instruction
of the kit. The highest calibration level is only 250 ppb and most of the sample
extracts needed extra dilutions for quantitative result. The absorbances were
measured with 650 nm with Tecan Infinite F200 microwell reader and Magellan
software. The acceptable correlation (r ≥ 0,995) of the calibration curve were not
achieved in the first day, but were excellent (r = 0.999) in 2 nd and 4 th day. The
variation between the absorbance values of the same calibration level was low,
because of close measurements days and the same lot number of used kits.
ELISA results of 20 oats samples were compared with LC-MS results. The slope
of the regression line was 1.226, so the ELISA gave little bit higher results than
LC-MS method. ELISA test worked quite well when sum concentration of T-2 and
HT-2 toxins was 25 - 250 ppb.
Keywords: T-2, HT-2, ELISA, correlation
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