AAS与ICP-MS法测定花生中镉含量的对比研究

Comparison Study on AAS and ICP-MS Determination of Cadmium Content in Peanut

使用石墨炉原子吸收(Graphite furnace atomic absorption spectrometry,AAS)和电感耦合等离子体质谱(Inductively coupled plasma mass spectrometry,ICP-MS)分别测定5批花生中镉的含量,将测得的结果数据进行对比分析,为花生中镉含量的测定提供实用可靠的检测方法。两种方法测得的花生中镉含量结果相对平均偏差均小于10%;线性范围:石墨炉原子吸收为0~5 ng/mL,ICP-MS为0~50 ng/mL;检出限:石墨炉原子吸收为0.02 ng/mL,ICP-MS为0.004 ng/mL;回收率:石墨炉原子吸收为91.8%~105.7%,ICP-MS为89.8%~95.3%;精密度:石墨炉原子吸收为2.27%,ICP-MS为1.70%。结果表明,两种方法都可以满足对花生中镉含量进行测定,对于同一来源的样品消解液,可以同时采用石墨炉原子吸收和电感耦合等离子体质谱进行测定,均可以保证测定数据的准确性。

The contents of cadmium in five peanuts were determined by graphite furnace atomic absorption spectrometry （AAS）and inductively coupled plasma mass spectrometry （ICP-MS）, the obtained results were compared and analyzed, so as to provide a reliable method for the determination of cadmium in peanut. The av-erage relative deviation of cadmium content got from two different measurement in peanut was less than 10%;Linear range：AAS was 0 to 5 ng/mL, ICP-MS was 0 to 50 ng/mL. Detection limit：AAS was 0.02 ng/mL, ICP-MS was 0.004 ng/mL. Recovery rate：AAS were 91.8%-105.7%, ICP-MS were 89.8%-95.3%. Precision：AAS was 2.27%, ICP-MS was 1.70%. The results indicated that the two methods can meet the requirement of cadmium content in peanut, and for the same sample digestion from the same source, it can be tested by graphite furnace atomic absorption spectrometry and inductively coupled plasma mass spectrometry at the same time, and both way can guarantee the accuracy.