原子吸收分光光度法间接测定奶粉中的乳铁蛋白含量

目的: 建立一种借助乳铁蛋白铁结合能力测定奶粉中乳铁蛋白的方法。 方法: 先通过额外加入的二价铁离子使乳铁蛋白中的铁达到饱和以获得稳定的铁含量,然后对蛋白反复醇沉和水溶以除去游离铁,再用原子吸收分光光度计测定铁含量,依据铁与蛋白含量的相互关系计算出乳铁蛋白含量。 结果: 该法快速准确,加样回收率超过96%,检测范围为3.5~100 mg·g^-1。 结论: 可以用于婴儿奶粉中乳铁蛋白的测定。

Objective: To develop an atomic absorption spectrophotometer method to determine the lactoferrin in milk powder based on its iron binding capability. Methods: Firstly,the iron in lactoferrin was saturated by additional ferrous ion to achieve a constant content.Then,the protein was precipitated by ethanol and dissolved in water repeatedly in order to get rid of the dissociated iron ion.The iron content was measured by atomic absorption spectrophotometer.Through the correlation between iron content and protein content,the lactoferrin content could be calculated. Results: The advantages of this method were speedy and accurate,which had a recovery above 96% and a broad detection ranging from 3.5 to 100 mg·g^-1. Conclusion :This method will be helpful to detect lactoferrin in infantile milk powder.