微波消解-ICP-MS同时测定母乳中Ca和P的方法研究

采用微波消解法作为保鲜母乳的样品前处理方法,应用电感耦合等离子体质谱(ICP-MS)法同时测定其中的Ca和P含量。通过优化试样消解条件及ICP-MS仪器测定条件,选择适宜的内标元素、同位素质量数、EPA200.8标准干扰校正方程,利用奶粉(GBW10017)国家标准物质及添加回收率实验验证方法的准确度与可靠性,元素测定值均在标准值允许范围内;试样平行测定相对标准偏差(RSD)≤2.40%,添加回收率在102.8%～104.0%。研究方法准确、可靠,线性动态范围宽,不必稀释样品,适合批量样品多元素同时分析,弥补了原有国家标准中不同元素不同方法分别测定的不足。

Method study on calcium and phosphorus simultaneous determination by microwave-digestion and ICP-MS

As a pre-digestion method of breast milk microwave-digestion was adopted in this method, and the contents of calcium and phosphorus were determined by ICP-MS at the same time. By optimizing conditions of digestion and ICP-MS, appropriate internal elements and the isotope mass number and EPA200.8 interference calibration equation were chosen. The accuracy and reliability of method were verified through the recovery and milk powder analysis of national standard substances (GBW10017). Determination results are in the permissible range. The relative deviation (RSD) is less than 2.40%, while the recovery is between 102.8% and 104.0%. ICP-MS method has wide dynamic range, and doesn't need to dilute samples. It is suitable for lots of samples and multi-element analyzed at the same time, and making up default of different method and different element determined respectively in national standard. It is a determination method for calcium and phosphorus supply of breast milk.