原子吸收光谱法测定营养品中钙钾镁铁的含量

Determination of Ca,K,Mg and Fe in Nourishments by FAAS

对藕粉、豆粉、芝麻糊、核桃粉中无机营养元素的含量进行考察.采用高氯酸-硝酸（1＋4）混酸消解的方法将样品在低温下消解,用镧盐作为钙、镁的释放剂以消除共存元素P的化学干扰,火焰原子吸收光谱法定量.实验测得Ca、K、Mg、Fe工作曲线的相关系数r〉0.991,加标回收率在99.31%-103.70%,相对标准偏差在2.06%以下.实验方法简单、快速、定量准确,测得各营养品中无机元素含量丰富,可作为无机营养元素的来源.

In this paper,the contents of trace elements in nourishments such as Ca,K,Mg and Fe were determined by flame atomic absorption spectrometry.Samples were treated with an incomplete digestion method.The samples were digested in a mixed acid of HClO4-HNO3（1 ＋ 4） under low temperature.Lanthanum salt was used as the releasing agent for calcium and magnesium.The results showed that each sample contains rich trace elements which are necessary for people.The linear correlation coefficients were more than 0.991,the spiked recovery ratio was between 99.31% and 103.70% and the RSD was less than 2.06%.This method is rapid,simple,sensitive,and accurate.The experimental results proved that these nourishments are rich in inorganic elements and can take as the source of inorganic nutrients.