用于研究ICP-MS中基体效应的逐级稀释法

用逐级稀释法研究了ICP-MS测定痕量稀土时的基体效应,并将该法对高纯稀土、土壤和生物等样品的实验结果与常用的加入基体法的结果进行了比较.结果表明,两种方法所得出的基体最大允许浓度值相近.与常规的基体效应研究方法相比,逐级稀释法操作简便、易行,无须使用任何高纯物质作基体,且适用于任何化学组成复杂的试样体系,在实际分析中具有应用价值.为了验证该方法的可靠性,对含不同基体的标准试样中的痕量稀土进行了测定,所得实验数据表明,测定值与参考值一致.

Stepwise Dilution Method for the Study of Matrix Effects in ICP-MS

A new method of stepwise dilution was proposed to study the matrix effects in the determination of REEs by ICP-MS. The highest tolerant level of matrix obtained by this method coincided with that obtained by the conventional method. Trace REEs in different samples were determined directly by ICP-MS without the use of internal standard and matrix matching and the determined values are in a good agreement with the certified values. Stepwise dilution method is a potential method in practical analysis with the advantages such as simplicity for operation, low cost, no need for higher purity matrix, without the use of internal standard and suitable to any other samples with complicated matrix.