Holbrook, T.; Gallot-Duval, D.; Reemtsma, T.; Wagner, S.
An investigation into LA-spICP-ToF-MS uses for in situ measurement of environmental multi-elemental nanoparticles.
Journal of Analytical Atomic Spectrometry, 2021.
DOI: 10.1039/D1JA00112D
Holbrook, T.; Gallot-Duval, D.; Reemtsma, T.; Wagner, S.
Machine learning: our future spotlight into single-particle ICP-ToF-MS analysis
Journal of Analytical Atomic Spectrometry, 2021
DOI:10.1039/D1JA00213A
In two recent publications in the Journal of Analytical Atomic Spectrometry, Holbrook and co-workers from the Helmholtz-Centre for Environmental Science (UFZ, Leipzig, Germany) describe a novel approach for the direct analysis of multi-element particles (MEPs) in solid environmental samples by combining laser ablation with single particle analysis. The proof-of-principle of this approach was first established using a quadrupole ICP-MS [1]. The two publications highlighted here make use of the multi-element detection capability of TOFWERK’s icpTOF R to gain deeper insight into the complex picture of MEPs.
The first paper directly compares the LA-sp-ICP-TOFMS method with the more conventional method based on liquid sample introduction via a nebulizer (neb-sp-ICP-MS). The comparison was made on standard AgAu core-shell particles and environmental samples collected from a road runoff basin. While only minimal sample preparation is required for the laser ablation sampling, conventional approaches require tedious extraction procedures. The authors found the LA-sp-ICP-TOFMS method to be suitable for the analysis of MEPs with the advantage of requiring minimum sample preparation and providing a more complete elemental particle fingerprint.
The focus of the second paper is the development of effective post-processing schemes for the type of large datasets produced by LA-sp-ICP-TOFMS. The authors present a machine-learning approach which automates the work of dataset labeling and classification. This allows for a quick and efficient method for inter-sample comparison based on the compositions of MEPs.
The two publications together demonstrate how to capitalize on the fast, multi-element detection capabilities provided by the icpTOF for the study of MEPs in environmental systems.
[1] Tuoriniemi, J., Holbrook, T.R., Cornelis, G., Schmitt, M., Stärk, H.J. and Wagner, S., 2020. Measurement of number concentrations and sizes of Au nano-particles spiked into soil by laser ablation single particle ICPMS. Journal of Analytical Atomic Spectrometry, 35(8), pp.1678-1686.
