Evaluation of accuracy and long-term stability of determination of 37 trace elements in geological samples by ICP-MS.
ICP-MS测定地质样品中37个元素的准确度和长期稳定性分析

A simple method for 37 trace element analyses of geological samples by ICP-MS has been developed and evaluated based on 146 measurements of AGV-1 and BHVO-1 obtained in five years.In this work,the investigation of compromise conditions for optimizing the ICP,the examining of the instrument sensitivity drift and the comparisons of determined values by ICP-MS and XRF were carefully carried out.Contrary to our common understanding,the instrument sensitivity is not always drift down,which depends on the instrument conditions as well as the element.In order to correct this kind of instrument sensitivity drift,both internal standard and external standard calibration methods were applied in our practical sample analysis.Most of the ICP-MS and XRF determined values for Rb,Sr,Zr and Nb in various geological samples(n=210)agree within 10%in terms of relative deviation.Our analytical results showed that most elements have good accuracy and long-term stability with the relative deviation and relative standard deviation(n= 146,among the determined values)lower than 5%.It is concluded that our proposed ICP-MS multi-element analysis method has good accuracy and long-term stability.