Spark Ablation of Solid Samples for Analysis by Inductively Coupled Plasma-Mass Spectrometry

Abstract

High-voltage spark ablation is used for the direct analysis of solid samples using ICP-MS detection. Separation of sample vaporization, excitation, and detection phenomena allows each event to be optimized independently, thereby facilitating (among other things) enhanced sampling efficiency. Qualitative evaluation of elemental constituents is demonstrated. A direct linear relationship between electron multiplier counts and concentration was observed for trace elements (ranging from 0.75 to 125 ppm) in a series of “pure” copper standards. It is significant that neither concentration normalization nor internal standardization procedures were required. Sample uptake and clean-out times are minimal. This technique can be applied for the direct determination of conductive samples (or materials that can be converted into conductive form) with little or no sample preparation. For such samples, spark ablation could serve as an alternative to laser sampling in cases where larger sampling sites (∼1–2 mm) can be tolerated. In contrast, this technique uses inexpensive instrumentation, is simple to operate, and shows good accuracy and precision, even in prototype form.