Ionic liquids and other liquid matrices for sensitive MALDI MS analysis

Towers, M. W. and Cramer, R. ORCID: https://orcid.org/0000-0002-8037-2511 (2016) Ionic liquids and other liquid matrices for sensitive MALDI MS analysis. In: Cramer, R. ORCID: https://orcid.org/0000-0002-8037-2511 (ed.) Advances in MALDI and Laser-Induced Soft Ionization Mass Spectrometry. Springer, pp. 51-64. ISBN 9783319048185 doi: 10.1007/978-3-319-04819-2_3

Abstract/Summary

Although liquid matrix-assisted laser desorption/ionization (MALDI) has been used in mass spectrometry (MS) since the early introduction of MALDI, its substantial lack of sensitivity compared to solid (crystalline) MALDI was for a long time a major hurdle to its analytical competitiveness. In the last decade, this situation has changed with the development of new sensitive liquid matrices, which are often based on a binary matrix acid/base system. Some of these matrices were inspired by the recent progress in ionic liquid research, while others were developed from revisiting previous liquid MALDI work as well as from a combination of these two approaches. As a result, two high-performing liquid matrix classes have been developed, the ionic liquid matrices (ILMs) and the liquid support matrices (LSMs), now allowing MS measurements at a sensitivity level that is very close to the level of solid MALDI and in some cases even surpasses it. This chapter provides some basic information on a selection of highly successful representatives of these new liquid matrices and describes in detail how they are made and applied in MALDI MS analysis.