Journal article

Authors list: Schneemann, J; Schäfer, KC; Spengler, B; Heiles, S

Publication year: 2022

Pages: 16086-16094

Journal: Analytical Chemistry

Volume number: 94

Issue number: 46

ISSN: 0003-2700

eISSN: 1520-6882

Open access status: Hybrid

DOI Link: https://doi.org/10.1021/acs.analchem.2c03247

Publisher: American Chemical Society

Abstract: 
Ambient mass spectrometry imaging (MSI) methods come with the advantage of visualizing biomolecules from tissues with no or minimal sample preparation and operation under atmospheric-pressure conditions. Similar to all other MSI methodologies, however, ambient MSI modalities suffer from a pronounced bias toward either polar or nonpolar analytes due to the underlying desorption and ionization mechanisms of the ion source. In this study, we present the design, construction, testing, and application of an in-capillary dielectric barrier discharge (DBD) module for post-ionization of neutrals desorbed by an ambient infrared matrix-assisted laser desorption/ionization (IR-MALDI) MSI source. We demonstrate that the DBD device enhances signal intensities of nonpolar compounds by up to 104 compared to IR-MALDI without affecting transmission of IR-MALDI ions. This allows performing MSI experiments of mouse tissue and Danaus plexippus caterpillar tissue sections, visualizing the distribution of sterols, fatty acids, monoglycerides, and diglycerides that are not detected in IR-MALDI MSI experiments. The pronounced signal enhancement due to IR-MALDI-DBD compared to IR-MALDI MSI enables mapping of nonpolar analytes with pixel resolutions down to 20 mu m in mouse brain tissue and to discern the spatial distribution of sterol lipids characteristic for histological regions of D. plexippus.

Harvard Citation style: Schneemann, J., Schäfer, K., Spengler, B. and Heiles, S. (2022) IR-MALDI Mass Spectrometry Imaging with Plasma Post-Ionization of Nonpolar Metabolites, Analytical Chemistry, 94(46), pp. 16086-16094. https://doi.org/10.1021/acs.analchem.2c03247

APA Citation style: Schneemann, J., Schäfer, K., Spengler, B., & Heiles, S. (2022). IR-MALDI Mass Spectrometry Imaging with Plasma Post-Ionization of Nonpolar Metabolites. Analytical Chemistry. 94(46), 16086-16094. https://doi.org/10.1021/acs.analchem.2c03247