电感耦合等离子体发射光谱法测定奶粉中的9种元素

目的探讨用电感耦合等离子体发射光谱法测定奶粉中钙、铁、锌、钠、钾、镁、铜、锰、磷9种元素的含量。方法用微波消解法处理奶粉样品,然后运用电感耦合等离子体发射光谱法分析样品,同时探讨了最佳消解奶粉样品和分析样品的条件。结果电感耦合等离子体发射光谱法测定中9种元素的方法检出限为0·05~50mg/kg,相对标准偏差为0·3%~4·5%,加标回收率为91·0%~105·8%。结论该方法具有操作简便、反应彻底、多种元素同时测定、检出限低、线性范围宽、干扰小等优点,并具有良好的准确度和精密度,适合奶粉中微量元素和常量元素的测定。

Analysis of nine kinds of elements contents in the milk powder by inductively coupled plasma-atomic emission spectrometry

Objective To establish a method of determination of nine kinds of elements contents in the milk powder by inductively coupled plasma-atomic emission spectrometry(ICP-AES).Methods The milk powder is analyzed by ICP-AES. At the same time, the optimum conditions of digesting and analyzing sample are chosen.Results The method detection limit of nine kinds of elements are in the range of 0.05-50mg/kg, the relative standard deviations are in the rang of 0.3%-4.5%,the recovery rate are in the range of 91.0%-105.8%.Conclusion The method has the advantage of simplicity, reacting completion, high sensitivity, wide range of linear and small distraction. The determined results are accurate and the reproducibility is good. The method is fit for the determination of micro-element and macro-element in the milk powder.