微波消解-火焰原子吸收光谱法测定市售3种珍珠粉中金属元素

采用微波消解法处理样品,用硝酸-双氧水(体积比6∶1)混合溶液作为消解剂进行微波消解,火焰原子吸收光谱法测定了市售3种珍珠粉中锌、钠、镁、铁、钙、铜、锰、锶等8种金属元素含量。8种元素检出限(3S/N)在0.000 6～0.024 8 mg/L,回收率95%～105%,相对标准偏差(n=10)<5%。试验结果表明:3种珍珠粉样品中8种金属含量的数值变化趋势较为一致,其中钙含量最高,含量均达34.15%以上,锰、锶、铁、钠的含量也较为丰富,均在94.74μg/g以上,而锌、镁、铜含量相对较少,均少于11.78μg/g。从珍珠粉的主要成分金属元素钙的含量测定结果可以推断出3种珍珠粉的品质有所差别,钙含量低的质量相对差。

FAAS Determination of Metal Elements in Three Kinds of Pearl Powder with Microwave Assisted Digestion

Flame atomic absorption spectrometry(FAAS) was applied to determinate eight metal elements,Zn,Na,Mg,Fe,Ca,Cu,Mn,Sr,in three kinds of pearl powder bought from market.The samples were digested with a mixture of HNO3 and H2O2(6∶ 1,φ) in a microwave and then detected by FAAS.Detection limits(3S/N) for eight elements were in the range of 0.000 6~0.024 8 mg/L.The recoveries were in the range of 95%~105% and RSD(n=10) was lower than 5%.The distribution of 8 metal elements in 3 kinds of pearl powder were similar.Ca was the most which was more than 34.15%.Mn,Sr,Fe,Na were more than 94.74 μg/g while Zn,Mg,Cu were less than 11.78 μg/g.The content of Ca indicated the quality difference among 3 kinds of pearl powder.The lower the content of Ca was,the worse the pearl powder's quality was.This paper provides a new and useful method for quality assessment of pearl powder by the contents of metal elements.