His kit uses the principle of Colloidal Gold Immunochromatography assay. It can detect Total Aflatoxin (AF) in samples, such as grain, fodder, etc. After adding the sample solution into the sample well of detect card, AF of the sample solution combine with the gold-labelled antibody, so as to prevent the combining of gold-labelled antibody with AF conjugate on the cellulose membrane. When the concentration of AF in the sample solution is more than the detection limit, the detect line do not show color reaction and the result is positive. When the concentration of AF in the sample solution is less than the detection limit, the detect line shows purple and the result is negative.