Establishment And Application Of The Determination Of ELISA-AFM₁in Dairy

Aflatoxin, as an etiological factor of cancer, is the metabolic product of Aspergillusflavus and Aspergillus parasiticus. Aflatoxin M1（AFM₁） is the product of hydroxylationmetabolism in corpore of Aflatoxin B1（AFB1） ingested by animal. After animal ingests thefeedstuff with AFB1B, AFM₁will be present in its milk. Therefore, AFM₁in the animal milk islimited strictly in respective countries and areas. However, the method which is generallyaccepted effective and large scale applied in industry to prevent and remove AFM₁isdeficient. As a result, promptly quantitative detection for AFM₁is the existent best way todegrade the detriment of Aflatoxin.Formula milk powder is a kind of usual edible milk product. We established a way todeterminate AFM₁in formula milk powder by ELISA. After the optimized experiment ofabstraction agent and abstraction method, we choose80%methanol and water-heatingcircumfluence in15minutes, abstraction and abstersion with trichloromethane, finallydetermination by Elisa. The result revealed that precision of this method is satisfactory sinceits relative deviation of parallel result is less than5%. And after adding AFM₁standardpreparation of density of0.25μg/kg、0.50μg/kg、1.0μg/kg respectively, the average recoveryis91.1%、92.6%、90.1%, while the detection sensitivity is0.05μg/kg.We undertook the control experiment to determinate AFM₁and AFB1in food with themethod of Elisa, GB5413.37-2010immunoaffinity chromatography and GB5009.24-2010.The relative deviation of10samples determinated with these three methods is less than5%,present no significant difference.We also determinated the current milk products by Elisa. The samples, including fluid,semisolid and solid, were bought from supermarket randomly, three pieces each type. Therelative deviation of each type is less than10%. after adding AFM₁standard preparation ofdensity of0.50μg/kg, the recovery is88.0%⁹3.2%.The result of detecting AFM₁in formula milk powder by Elisa in this research has nosignificant difference with TLC or immunoaffinity chromatography, moreover, this methodhas advantages, such as simple operation steps, relatively low price, low density of contacttoxin, low requirement to laboratory apparatus, thus it can be applied to determinate AFM₁in formula milk powder. Furthermore, detecting current milk products including fluid, semisolidand solid, we found its average recovery could be over88%. As a result, it is referred todairy.