Direct introduction of powdered samples into an inductively coupled plasma mass spectrometer using a spark dispersion-merging sample introduction technique

Abstract

By using a spark dispersion-merging sample introduction technique, the direct multi-element analysis of over 40 elements including the rare earth elements (REE) were performed on four geological standard rocks (JB-1, -2 and -3 and JG-1) by inductively coupled plasma mass spectrometry (ICP-MS). About 1 mg of powdered sample was loaded on to a discharge cell placed in a merging chamber and the dispersed sample was led to the ICP with a blank aerosol sprayed from the nebuliser. The relative sensitivity factors (RSFs) of the REE were all found to be similar. This indicates that the internal standardisation method is effective for the determination of REE. For other elements, however, the RSFs were significantly different from those for the REE; the values of volatile elements such as I, TI and Bi were high, and those of refractory elements such as Ti and Zr were low. By using a standard rock sample as a calibration standard, the semi-quantitative determination of over 40 elements could be performed on one sample in a few minutes. In these analyses, the differences from reported values were better than ±30% for most of the elements, including the REE. The detection limit was better than 100 ng g^–1 and an absolute detection limit of 100 pg could be obtained for most elements.