Park D L, Miller B M, Hart L P, Yang G, McVey J, Page S W, Pestka J, Brown L H
Food and Drug Administration, Division of Contaminants Chemistry, Washington, DC 20204.
J Assoc Off Anal Chem. 1989 Mar-Apr;72(2):326-32.
A joint AOAC/IUPAC (International Union of Pure and Applied Chemistry) interlaboratory study of an enzyme-linked immunosorbent screening assay (ELISA) for aflatoxins was conducted in laboratories in Canada, France, Japan, South Africa, Switzerland, The Netherlands, Tunisia, and the United States. Twenty-eight samples of raw and roasted peanuts, corn, whole cottonseed, cottonseed meal, ammoniated cottonseed meal, and poultry feed containing various quantities of natural aflatoxins and supplemented when appropriate with aflatoxin B1 were distributed to participating laboratories for testing. The assay is based on conjugation of pure aflatoxin B1 to an enzyme and the competition between this conjugate and (free) aflatoxins in the product for aflatoxin-specific antibodies coated onto microtiter well walls. After a wash step to remove all unbound aflatoxins, a substrate, added to each well, is catalyzed from a colorless to a green solution by any bound enzyme-conjugated aflatoxin B1 present. The intensity of the color decreases as the amount of free aflatoxin B1 in the product increases. Overall correlation was good between ELISA and thin-layer chromatographic (TLC) results for cottonseed products and mixed feed. Variable results were reported for corn and peanut product samples. Although some positive samples (greater than 15 ng/g) of cottonseed products and mixed feed were reported to contain less than 15 ng/g by visual determination, a review of data for absorbance measurements showed that the contamination level was close to the greater than or equal to 15 ng/g standard and would not have been reported as negative under routine screening.(ABSTRACT TRUNCATED AT 250 WORDS)
美国官方分析化学师协会（AOAC）与国际纯粹与应用化学联合会（IUPAC）联合开展了一项针对黄曲霉毒素的酶联免疫吸附筛查测定法（ELISA）的实验室间研究，参与实验室分布在加拿大、法国、日本、南非、瑞士、荷兰、突尼斯和美国。向参与实验室分发了28份生的和烤制的花生、玉米、全棉籽、棉籽粕、氨化棉籽粕以及含有不同数量天然黄曲霉毒素并在适当情况下添加了黄曲霉毒素B1的家禽饲料样本进行检测。该测定法基于将纯黄曲霉毒素B1与一种酶结合，以及该结合物与产品中的（游离）黄曲霉毒素在包被于微量滴定板孔壁上的黄曲霉毒素特异性抗体上的竞争。经过洗涤步骤以去除所有未结合的黄曲霉毒素后，向每个孔中添加的底物会被存在的任何结合了酶的黄曲霉毒素B1从无色催化为绿色溶液。随着产品中游离黄曲霉毒素B1含量的增加，颜色强度会降低。对于棉籽产品和混合饲料，ELISA结果与薄层色谱（TLC）结果之间的总体相关性良好。玉米和花生产品样本的结果存在差异。尽管一些棉籽产品和混合饲料的阳性样本（大于15纳克/克）经目视测定报告含量低于15纳克/克，但对吸光度测量数据的审查表明，污染水平接近大于或等于15纳克/克的标准，在常规筛查下不会被报告为阴性。（摘要截取自250字）
