采用高效液相色谱荧光法测定牛奶中的黄曲霉毒素M1。牛奶中的黄曲霉毒素M1用乙腈超声提取，离心，上清液浓缩后用50 mL PBS缓冲液稀释，过免疫亲和层析柱净化，10%甲醇水溶液10 mL淋洗柱，2 mL甲醇洗脱，洗脱液氮吹干后，用10%乙腈水溶液1 mL蜗旋溶解残渣，过0.22μm滤膜，上机测定。对加入乙腈比例、淋洗液及洗脱液进行了优化，结果表明：m 牛奶：V 乙腈=1：2有效的沉淀蛋白避免了过柱堵塞问题，提高了过柱效率。用10%甲醇水溶液淋洗免疫亲和柱，能有效的去除掉杂质，避免了洗脱液成浑浊现象。该方法的线性范围宽，回收率为89.1%~93.5%，相对标准偏差在6.5%~9.7%之间，检出限为0.01μg/kg，低于1/10现行食品安全国家标准对食品中黄曲霉毒素M1的限量标准，符合检测要求，适用于对牛奶中黄曲霉素素M1的检测。%Aflatoxin M1 in milk were determinated using high-performance liquid chromatography with fluores-cence detection. Aflatoxin M1 in milk were firstly ultrasonic extracted ,centrifuged ,concentrated and then purified through immunoaffinity column,using 10%methanol aqueous solution leaching column,dried in nitrogen,vol-umed by 10%acetonitrile aqueous. The ratio of addition acetonitrile,leaching solution and eluent were optimized. The results showed that the ratio of the milk sample to acetonitrile was 1 to 2 in mass to volume could effectively pre-cipitate protein and avoid the column plug. Washing immunoaffinity column with 10%methanol aqueous can ef-fectively remove impurities and avoid the turbid phenomenon of eluent. The recovery of method with widely linear range was between 89.1%to 93.5%,relative standard deviation between 6.5%to 9.7%and the detection limit is 0.01μg/kg which was less than 1/10 of current national food safety standards with limit the quantity of aflatoxin M1. The method can be applied to the determination the content of aflatoxin M 1 in milk sample.
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