Detection of melamine using commercial enzyme-linked immunosorbent assay technology
Detection of melamine using commercial enzyme-linked immunosorbent assay technology
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DOI：
10.4315/0362-028x-71.3.590
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发表时间：
2008-03-01
影响因子：
2
通讯作者：
Garber, Eric A. E.
中科院分区：
文献类型：
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作者：
Garber, Eric A. E.
最近发生的三聚氰胺掺假事件促使人们需要快速可靠的筛查方法。为了满足这一需求，对用于检测三嗪类药物的商用酶联免疫吸附试验（ELISA）试剂盒进行了评估。最近发布的三聚氰胺检测试剂盒（Abraxis，宾夕法尼亚州沃明斯特）显示，磷酸盐缓冲盐水（PBS）中三聚氰胺的检出限为9 ng/ml，添加到狗粮中的三聚氰胺检出限约为1 μ g/ml。Abraxis生产的阿特拉津ELISA检测试剂盒需要0.2 mg/ml才能产生超过背景标准偏差4倍的响应。相比之下，使用EnviroGard三嗪板试剂盒（Strategic Diagnostics, Inc., Newark, Del.）， PBS中1.5 mg/ml三聚氰胺产生的信号仅与背景值有一个标准偏差，这不足以确定检测限。用105 mM磷酸钠/75 mM NaCl/2.5%脱脂牛奶/0.05% Tween 20 （UD）稀释提取，与制造商推荐的提取方法（提取到60%甲醇，超声，离心，过滤，再稀释到10%甲醇/PBS）相比，狗粮中三聚氰胺的检出率降低了五倍。使用Abraxis三聚氰胺酶联免疫吸附试验，两种提取方案在含有三聚氰胺的狗粮样品中获得了相同的结果。在狗粮肉汁中添加三聚氰胺的回收率为74%±4%。总之，最近发布的测定三聚氰胺的Abraxis ELISA被证明是一种有用的替代方法。
Recent cases of adulteration with melamine have led to the need for rapid and reliable screening methods. To meet this need, commercial enzyme-linked immunosorbent assay (ELISA) test kits for the detection of triazines were evaluated. The recently released Melamine Plate kit (Abraxis, Warminster, Pa.) displayed a limit of detection of 9 ng/ml for melamine in phosphate-buffered saline (PBS) and approximately 1 mu g/ml for melamine added to dog food. An atrazine ELISA test kit produced by Abraxis required 0.2 mg/ml to generate a response more than four times the standard deviation from background. In contrast, with the EnviroGard Triazine Plate kit (Strategic Diagnostics, Inc., Newark, Del.), 1.5 mg/ml melamine in PBS generated a signal only one standard deviation from background, which was insufficient to define a limit of detection. Extraction based on dilution with 105 mM sodium phosphate/75 mM NaCl/2.5% nonfat milk/0.05% Tween 20 (UD) enabled detection of fivefold less melamine in dog food than did use of the procedure recommended by the manufacturer, which entailed extraction into 60% methanol, sonication, centrifugation, filtration, and further dilution into 10% methanol/PBS. Using the Abraxis Melamine ELISA, both extraction protocols yielded identical results with a dog food sample adulterated with melamine. The recovery of melamine spiked into gravy from dog food using UD was 74% +/- 4%. In conclusion, the recently released Abraxis ELISA for melamine proved to be a useful alternative to more cumbersome methods.