文档介绍：【摘要】  目的尝试建立一种快速准确地测定奶粉中蛋白质含量的方法。方法使用三氯乙酸沉淀蛋白质后,运用BCA(二喹啉甲酸)法,在570 nm波长处,分别测定标准蛋白质应用液与样品稀释液的吸光度值,基于测定液中蛋白质含量与其吸光度值呈正比关系,计算出样品中蛋白质的含量。结果待测溶液中蛋白质浓度在0~250 μg/ml 范围内标准曲线呈线性关系,其回归方程为:Y=-,相关系数r=,%。结论结合三氯乙酸沉淀的BCA法适用于奶粉中蛋白质的快速检验和掺伪检验。
【关键词】  奶粉;蛋白质;BCA法;三氯乙酸;三聚氰胺
A rapid and simple method of protein determination in powdered milk
    Zhang Zhiqiao, Shen Guodong, Wang Gang
    First Middle School of Hefei, Anhui Provincial Hospital Affiliated to Anhui Medical University, Hefei 230001
   
[Abstract]Objective  To explore a rapid and simple method of protein determination in powdered milk without other nitrogen-pound disturbance in Kjeldahl   Conjugated with protein precipitation with trichloroacetic acid, BCA (bicinchoninic acid) method was used. According to the positive relationship of protein content with the 570 nm absorbance, protein content was calculated in powdered   Protein content in milk solution showed a good linear relationship at the detection ranges of 0-250 μg/ml, with regression equation: Y=- and related coefficient: , and the average recovery rate was %.Conclusion  BCA method conjugated with trichloroacetic acid is adaptable to the rapid and sensitive determination of protein in powdered milk.
   
[Key words]Powdered milk; Protein; BCA method; Trichloroacetic acid; Melamine