Outlook

What will LA-ICP-MS look like in future?

The femtosecond laser provides a laser source with ultrashort pulse duration, which allows the ablation process with an insufficient time for photon energy to dissipate into the target lattice to heat and induce melting before the explosive release of sample material. Thus the femtosecond laser may substantially eliminate the laser-induced element fractionation (Russo et al., 2002).

Simultaneous mass analyzer detection systems (MC-ICP-MS, TOF-ICP-MS) are ideal for measuring transient laser ablation signals due to the recorded ion intensities are exactly reflected the compositional variations of the target material, which may occur more abruptly for the sequence mass analyzer (quadruple (Q)-ICP-MS and single collector ICP-MS).

Recently, the excellent potential for LA-TOF-ICP-MS has been demonstrated for the capability of high-speed multi-element analysis (Gundlach-Graham and Günther, 2016).

Therefore we can imagine that the widespread adoptions of the user-friendly femtosecond laser ablation system coupled to the simultaneous mass analyzer detection systems (MC-ICP-MS and TOF-ICP -MS) in the near future. Meanwhile, the ultrafast response

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ablation cell and more powerful data reduction software are also expected.

What could we do with the current and new generation of LA-ICP-MS?

With the intensive improvement of LA-ICP-MS, we could conduct lot things either in methodology development or applications for the serving Earth science. Here I listed some of them, which is already “work in progress”.

Methodology:

(1) Laser ablation split stream techniques (LISS) allows concurrent elemental and isotopic analysis of the same ablation volume, which makes the interpretation of isotopic ratios or dates in light of complementary geochemical information (Kylander-Clark et al., 2013).

(2) 2D/3D trace element mapping (Raimondo et al., 2017; Ubide et al., 2015) as a tool for visualizing and quantifying internal structure of trace element concentration in igneous minerals

(3) Nanopowder pellets technique for the enhancement the LA-ICP-MS capability in bulk rock analysis (Garbe-Schönberg and Müller, 2014) and for the development of matrix-matched reference materials (Tabersky et al., 2014).

Applications:

(1) Zircon Pb-U and Th-U dating at a young age (10-300 ka) (Guillong et al., 2016; Guillong et al., 2014)

(2) In-situ high precision isotopic ratio analysis, for example, Li isotope composition in single crystal (e.g. zircon) for understanding the diffusion derived fractionation.

(3) High precision elemental ratio determination, especially for these elements suffered from incomplete dissolution in solution ICP-MS measurements, for example, Nb/Ta, Zr/Hf, etc.

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Reference

Garbe-Schönberg D, Müller S (2014) Nano-particulate pressed powder tablets for LA-ICP-MS. J. Anal. At. Spectrom. 29 (6): 990-1000

Guillong M, Sliwinski JT, Schmitt A, Forni F, Bachmann O (2016) U‐Th Zircon Dating by Laser Ablation Single Collector Inductively Coupled Plasma‐Mass Spectrometry (LA‐

ICP‐MS). Geostand. Geoanal. Res. 40(3): 377-387

Guillong M, von Quadt A, Shuhei S, Bachmann O, Peytcheva I (2014) LA-ICP-MS Pb-U dating of young zircons from the Kos-Nisyros volcanic centre, SE Aegean arc. J. Anal. At.

Spectrom. 29(6): 963-970

Gundlach-Graham A, Günther D (2016) Toward faster and higher resolution LA–ICPMS imaging: on the co-evolution of LA cell design and ICPMS instrumentation. Anal. Bioanal.

Chem. 408(11): 2687-2695

Kylander-Clark AR, Hacker BR, Cottle JM (2013) Laser-ablation split-stream ICP petrochronology. Chem. Geol. 345: 99-112

Raimondo T, Payne J, Wade B, Lanari P, Clark C, Hand M (2017) Trace element mapping by LA-ICP-MS: assessing geochemical mobility in garnet. Contributions to Mineralogy and Petrology. 172(4): DOI 10.1007/s00410-00017-01339-z

Russo RE, Mao XL, Liu HC, Gonzalez J, Mao SS (2002) Laser ablation in analytical chemistry - a review. Talanta. 57(3): 425-451

Tabersky D, Luechinger NA, Rossier M, Reusser E, Hametner K, Aeschlimann B, Frick DA, Halim SC, Thompson J, Danyushevsky L, Gunther D (2014) Development and

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characterization of custom-engineered and compacted nanoparticles as calibration materials for quantification using LA-ICP-MS. J. Anal. At. Spectrom. 29(6): 955-962

Ubide T, McKenna CA, Chew DM, Kamber BS (2015) High-resolution LA-ICP-MS trace element mapping of igneous minerals: In search of magma histories. Chem. Geol. 409:

157-168

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Appendix A: Curriculum vitae Shitou Wu

Date of birth: 28.09.1987 Place of birth: Hebei (China)

Scientific education:

07/2011 Bachelor of sciences (Analytical chemistry) Thesis: Structure and Corrosion Resistance of γ-APS

(γ-Aminopropyltriethoxysilane) Silane Film on Low Carbon Steel

07/2013 Master of sciences (Environmental chemistry)

Thesis:The Evaluation of Rare Earth Elements Analytical Methods in Bayun Obo Rare Earth Ore Reference Material Candidates and A Preliminary Study on The Rare Earth Elements Speciation

10/2013-08/2017: Doctorate at the Geoscience Center Göttingen (Geochemistry) Thesis:Laser Ablation-Inductively Coupled Plasma-Mass Spectrometer (LA-ICP-MS) in Geosciences: Further Improvement for Elemental Analysis (supervisor: Prof Gerhard Wörner and Dr. Klaus Simon)

Work experience:

2013-2017: LA-ICP-MS laboratory assistant

Field experience:

2014 Germany 2 days Regionale Geologie der Umgebung von Göttingen (Nordhessen) 2015 Germany 2 days Magmatite und Metamorphite (Harz)

2015 Germany 2 days Sedimentgesteine und Fazies 2016 Germany 1 week Vulkanfeldkurs (Laacher See)

191 Short course:

08/2015 Application of diffusion studies to the determination of timescales in geochemistry and petrology. Bochum

11/2015 Introduction to Secondary Ion Mass Spectrometry in the Earth Sciences. Potsdam 02/2017 MATLAB Recipes for Earth Sciences. Potsdam

03/2017 Radiogenic and Non-tradional Isotope short course, Frankfurt

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Appendix B: Publications Manuscripts and Articles*

 Shitou Wu* and Klaus Simon. (2017) Signal enhancement in LA-ICP-MS analysis by guard electrode and the addition of nitrogen and hydrogen into carrier gas flow: A perspective from experiment (in preparation for “Journal of Analytical Atomic Spectrometry”)

 Shitou Wu*, Volker Karius, Burkhard C Schmidt, Klaus Simon and Gerhard Wörner. (2017) Comparison of ultrafine powder pellet and flux-free fusion glass for bulk analysis of granitic rock samples by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry. (“Geostandards and Geoanalytical Research”, under review)

 Shitou Wu* and Klaus Simon. (2017) LA-ICP-MS transient signal quantification of NIST, MPI-DING, USGS, and CGSG glass reference materials by Ratioing, Standardization, and Normalization (RSN) (“Geostandards and Geoanalytical Research”, under review).

 Shitou Wu, Yaping Wang*, and Chunxue Xu. (2017 )Laser ablation-inductively coupled plasma-mass spectrometer: A quantification strategy based on two reference materials and bulk normalization as 100% (wt). Chinese Journal of Analytical Chemistry. 45(7): 965–972.

 Shitou Wu, Chunxue Xu, Klaus Simon, Yilin Xiao and Yaping Wang. (2017) Ablation behaviors of 193nm ArF excimer laser system for the selected substrates. Rock and Mineral Analysis.

(Accepted, in Chinese with English abstract).

 Shitou Wu, Yaping Wang*, Chunxue Xu and Jihai Yuan. (2016) Elemental fractionation studies of 193 nm ArF excimer laser ablation system at high spatial resolution. Chinese Journal of Analytical Chemistry. 44(7): 1035–1041.