Advancements in Laser-Induced Breakdown Spectroscopy (LIBS) to Improve Online Elemental Analysis of Aerosols

Aerosols can have significant impact on the environment and health based on their chemical composition. It’s imperative to understand the chemical composition at the single particle level as it has influence on ice nucleation potential, cloud condensing nuclei potential and radiative forcing.¹ Laser-induced breakdown spectroscopy (LIBS) is an emerging technique for online analysis of single particle aerosol composition. LIBS requires no vacuum pump or sample preparation which is more advantageous for field deployment compared to other laser-based elemental composition techniques such as mass spectrometry.⁴ In brief, LIBS uses a high-powered laser to ablate particles resulting in a plasma of excited atoms of whose atomic emissions can be measured.² Recently, linear electrodynamic quadruples have been employed to improve particle alignment and spacing.^4,5 Several data processing methods have also been developed to improve detection limits, the most notable being “conditional” analysis.^2,3 Conditional analysis allows for low concentration measurements through a calibration that relates particle detection rate and mass concentration to reduce underestimation by missed particles, improving detection up to two orders of magnitude.⁶ In this presentation, we explore how these different online aerosol elemental composition analysis LIBS methods are being utilized and directing current research.

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5. Heikkilä, P.; Rostedt, A.; Toivonen, J.; Keskinen, J. Analysis and Classification of Individual Ambient Aerosol Particles with Field-Deployable Laser-Induced Breakdown Spectroscopy Platform. Aerosol Sci. Technol., 58 (9), 1063–1078, (2024). doi: 10.1080/02786826.2024.2350022.
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