Elemental Analysis by Mass Spectrometry

Three direct solid analysis mass spectrometric techniques allowing for lateral and/or depth resolution have been selected in this section laser ablation (LA) coupled to ICP-MS, secondary ion mass spectrometry (SIMS) and GD-MS. 

LA-ICP-MS is suitable for the direct analysis of materials such as metals, semiconductors, ceramics and insulators at trace and ultratrace levels (detection limits 1 ng g ) without sample preparation. The MS detection mode makes it possible isotope analysis and also isotope dilution methods using 

Instruments based on GD-MS coupling have been employed most commonly for the quantitative analysis of trace and ultratrace amounts in high-purity materials. However, it has been demonstrated that, as in GD-OES, quantitative depth profile analysis by GD-MS is possible [33]. At present, a GD-MS prototype which allows the depth quantification of thin layers on conducting or insulating materials is being developed for commercial purposes [34]. 

Zybin and K. Niemax, Narrow and broad band diode laser absorption spectrometry - concepts, limitations and applications, Spectro-chim. Acta. Part B, 57, 2002, 1547-1561. 

Heitmann, M. Schutz, H. Becker-Ross and S. Florek, Measurements on the Zeeman-splitting of analytical lines by means of a continuum source graphite furnace atomic absorption spectrometer with a linear charge coupled device array, Spectrochim. Acta Part B, 51, 1996, 1095-1105. 

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Elemental analysis by mass spectrometry. A particular high-resolution mass spectrometer measures m z to an accuracy of 10 parts per million. This means that miz 100 can be measured to an accuracy of (100)(10 X 10 ) = 0.001 (and precision into the next decimal place). A molecular ion thought to be C4HnN3S or C4H11N3O2 was observed at m z 133.068 6. Compute the expected mass of each ion by adding the masses of the correct isotope of each atom and subtracting the mass of an electron. Which formula is correct ... 

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