Comparison of inductively coupled plasma mass spectrometry with a microconcentric nebuliser and total reflection X-ray spectrometry for the analysis of small liquid volume samples

Abstract

Inductively coupled plasma mass spectrometry (ICP-MS) incorporating a microconcentric nebuliser was compared with total reflection X-ray spectrometry (TXRF) for the analysis of small volume samples. The techniques were evaluated by accurate analysis of reference materials CASS-2, SLEW-1 and WRc Aquacheck samples distribution 143 and 147 using only microvolumes of sample. Recoveries from spiked reference samples were in the range 93-109%. The methods were then applied to the analysis of a new material with a polymer matrix that was only available in small amounts for testing. ICP-MS and TXRF gave quantitative elemental data for the polymer samples. Comparing the two methods, TXRF offered the potential of fast effective screening using just 10 µl. Organic solutions could be analysed directly, although the polymer samples needed digestion for accurate TXRF analysis. ICP-MS offered better detection limits for a wider range of elements but at least 90 µl of sample were required and digestion of the sample was essential.