电感耦合等离子体-质谱法内标元素选择的研究

电感耦合等离子体-质谱(ICP-MS)测定土壤标样中不同质量段的Cr、Cd、Pb元素,借以研究内标元素选择对测定值的影响。结果表明:选择内标元素,首要考虑因素是样品中不含该元素,而非质量数或第一电离能与待测元素接近;选择样品中含有成分作为内标元素时,对低浓度含量的元素影响更大;单一内标元素即可校正基体效应,实现对低、中、高质量段的多元素同时测定。对地质标样和未知样品,分别推荐了内标元素和选择内标元素的方法。

Study on Selection of Internal Standard Element of ICP-MS

Element Cr, Cd, Pb of different mass quality section was determined by ICP-MS, which was aimed to study the influence of internal standard element to measured values. The obtained results indicated as follows:the primary consideration of the internal standard element was element which wasn't contained in the samples, and not close to the mass quality and the first ionization energy between the internal standard element and element to be analyzed; the impact on the low concentration of elements was greater if choosing element contained in samples as the internal standard element; the matrix effect and the different mass quality elements were able to be corrected and determined separately with single internal standard element. To geological standard samples and unknown samples, the internal standard elements and the selecting its method were respectively recommended.