电感耦合等离子体质谱(ICP-MS)法与氢化物发生-原子吸收光谱(HG-AAS)法测定土壤中硒含量的对比研究

基于氢化物发生器与原子吸收光谱联用(HG-AAS),测定土壤样品中硒的含量,并与电感耦合等离子体质谱(ICP-MS)法测定值进行了对比。在两种仪器的最佳工作条件下,测定土壤硒的含量,实验结果表明:ICP-MS法和HG-AAS法对土壤硒含量测定的线性范围分别为0.85~100.00μg/L和0.08~16.00μg/L,检出限分别为0.25μg/L和0.02μg/L,精密度分别为1.3%和2.1%;用加标回收实验和测定国家标准土壤样品(GSS-7)对这两种方法的准确性进行了验证,ICP-MS法和HG-AAS法的加标回收率分别为96.7%~99.4%和94.9%~99.5%,GSS-7标准土样的结果均在标准值范围内,说明这两种测定土壤中硒含量的方法是准确可靠的。HG-AAS法测定线性范围窄,部分样品需要稀释,而且氢化物发生系统是手动进样,导致操作复杂,分析周期长;ICP-MS法仪器测定快速,但是仪器昂贵。

Method Comparison for Determination of Selenium in Soil by ICP-MS and HG-AAS

Based on hydride generator and atomic absorption spectrometry(HG-AAS),selenium content in soil samples was determined and compared with inductively coupled plasma-mass pectrometry(ICP-MS).The selenium content of soil was determined under the best working conditions of the two instruments.The experimental results showed that the analytical calibration curves of selenium in soil were ranging from 0.85-100.00μg/L for ICP-MS and 0.08-16.00μg/L for HG-AAS,the detection limits were 0.25μg/L and 0.02μg/L,the precision of the two methods were 1.34%and 2.12%,respectively.The accuracy and reliability of the two methods were verified by recovery rates test and the results of the soil environment samples of certified reference materials(GSS-7).The recovery rates were 96.7%-99.4%for ICP-MS and 94.9%-99.5%for HG-AAS and the measure results of GSS-7 were in the range of standard values range,suggesting the two methods were accurate and reliable.Some samples have to be diluted due to the narrow linear range of HG-AAS,and the hydride generation system is needed manual injection,resulting in complex operation and longer determination period,while the assay of ICP-MS is rapid and expensive.