Inductively coupled plasma mass spectrometry laser ablation-ICPMS

This presentation will summarize developments in laser ablation with emphasis on LIBS (laser induced breakdown spectroscopy) and inductively coupled plasma mass spectrometry (ICPMS) as analytical tools for real time chemical analysis (Fig. 1) (Russo et al. 

This chapter does not cover analytical techniques, and assumes that the reader is at least moderately familiar with the electron microprobe, ion microprobe, and laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS), as well as with the distinction between X-ray mapping and spot analysis by electron microprobe. Mineral abbreviations are after Kretz (1983). 

Laser-ablation, inductively coupled-plasma mass spectrometry (LA-ICPMS) is an instrumental technique in which a laser-ablahon cell and ophcal microscope supplant the spray chamber/nebulizer apparatus of a standard ICP-MS instrument. Subsamples of questioned material are ablated from a solid sample via laser (often a pulsed Nd-YAG tuned to 266 or 213 nm). Ablated specimens are transported in a stream of Ar to a plasma torch for ionization and mass discrimination as per solution ICP-MS. Only minimal sample prep is required, and few restrictions are placed on the nature of questioned solid samples (Brundle et al. 1992 Vickerman 1998). While laser spot sizes can be reduced to several micrometers, sensitivity is degraded as a result, and usual spatial resolutions are on the order of 10-100 pm. Matrix-matched standards are also necessary for accurate trace-element and isotopic quantitative analyses in LA-ICPMS. Depending on the quality of such primary standards, LA-ICPMS accuracies are typically 1-10%, with limits-of-detection in the parts-per-billion (ppb) range (O Table 62.1). 

Jackson,S.E.,Longerich,H.P.,Dunning, G.R.,Dunning,B., Dunning, F. (1992) The application of laser ablation micro-probe inductively coupled plasma-mass spectrometry (LAM-ICPMS) to in situ trace element determinations in minerals. Canadian Mineralogist, 30,1049-1064. 

A wish list of the main requisites that a technique should fulfill for its use in elemental archaeological research would certainly include the following aspects (1) nondestructive or minimally destructive nature (2) minimal sample preparation, regardless of the type of sample targeted (3) potential to achieve simultaneous multielemental data for major, minor, and trace elements in a straightforward way (4) capabilities for isotopic analysis and (5) potential to provide spatially resolved information, laterally, and in depth. Nowadays, the technique that complies with all of these requirements to the largest extent is laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS). 

In the same year, combination with laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) was first carried out on cellulose TLC plates... 

Longerich, H. (2008) Laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS), in Laser Ablation ICP-MS in the Earth Sciences Current Practice and Outstanding Issues (ed. P. Sylvester), Short Course Series, vol. 40, Mineralogical Association of Canada, Quebec, pp. 11-18. 

Laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS)... 

With the advent of multiple-collector inductively coupled plasma-source mass spectrometry (MC-ICPMS) it is now possible to measure Mg/ Mg and Mg/ Mg of Mg in solution with a reproducibility of 30 to 60 ppm or better (Galy et al. 2001). What is more, ultraviolet (UV) laser ablation combined with MC-ICPMS permits in situ analysis of Mg-bearing mineral samples with reproducibility of 100 to 200 ppm (Yoimg et al. 2002a). These new analytical capabilities allow mass-dependent fractionations of the isotopes of Mg to be used as tracers in natural systems. 

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