COMPARISON OF IMMUNOASSAY AND GAS-CHROMATOGRAPHY METHODS FOR THE DETECTION OF THE MYCOTOXIN DEOXYNIVALENOL IN GRAIN SAMPLES

The deoxynivalenol (DON) concentration in grain samples of wheat and c orn, inoculated with Fusarium graminearum in the field, was determined by gas chromatography and competitive direct (CD)-ELISA using monoclo nal antibodies. The two methods gave similar results with no false pos itives or negatives. Based on analyses of 140 wheat and 83 corn sample s, the correlation coefficient (r) between the two methods was 0.984 /- 0.015 for wheat and 0.986 +/- 0.018 for corn (P = 0.0001 for both). The slopes for the regression analysis of the corn and wheat data wer e 1.012 +/- 0.019 and 1.099 +/- 0.017, respectively. If only lower con centrations were considered, the 28 corn samples with DON concentratio ns below 5 ppm yielded a slope of 1.251 +/- 0.109 (r = 0.914 +/- 0.063 ), and the 63 wheat samples with DON concentrations below 2 ppm produc ed a slope of 1.220 +/- 0.132 (r = 0.763 +/- 0.083).