REVIEW OF SOLID SAMPLE INTRODUCTION FOR PLASMA SPECTROMETRY AND A COMPARISON OF RESULTS FOR LASER-ABLATION, ELECTROTHERMAL VAPORIZATION, AND SLURRY NEBULIZATION

The relative merits of three solid sample introduction techniques for inductively coupled plasma atomic emission spectroscopy and inductivel y coupled plasma mass spectrometry have been evaluated. The techniques studied were laser ablation (LA), slurry nebulization, and slurry int roduction via electrothermal vaporization. The application of each tec hnique to the quantification of Pa and Pb in geochemical samples has b een described and the results obtained for each technique have been co mpared. To help in assessing the potential of the systems described he re a simple classification of the agreement obtained between found and known values has been proposed allowing a comparison of these results with other results published in the literature to be made. Problems e ncountered during the evaluation of the techniques have been described and, for LA, the associated problems have led to the development of a modified sampling system which was used in an investigation of some f undamental aspects of LA as a method of solid sample introduction. Pos sible routes for improvement in sampling and transport are suggested, including use of reactive gases, ablation under stopped flow condition s and removal of large particles by gravitational settling. (C) 1994 A cademic Press, Inc.