Česká společnost pro hmotnostní spektrometrii

(13. ročník České konference hmotnostní spektrometrie a 11. Neformální proteomické setkání - WeS-03)
rDUVLAESCI-MS/MSI: a novel approach for direct analysis of biological surfaces

Jakub Grepl ¹, Barbora Papoušková ¹, Filip Gregar ¹, Karel Lemr ¹, Petr Fryčák ¹, Tomáš Pluháček ^1 *

1. Univerzita Palackého v Olomouci

Abstrakt

Ambient mass spectrometry has significantly enhanced the insight into the molecular composition of complex biological surfaces under native conditions, requiring minimal sample preparation [1]. Advancements in laser-based designs, including UV and deep UV lasers, enabled non-destructive, low-fragmentation analysis of various solid samples and dried spots/layers while significantly improving spatial resolution for mass spectrometry imaging (MSI) to just a few micrometers [2]. The presented work introduces a novel, fully automated Remote Deep-Ultraviolet Laser Ablation coupled with Electrospray Ionization−Atmospheric Pressure Chemical Ionization (rDUVLAESCI) ionization source, which can be easily used for either spot analysis or MSI of a wide range of polarity and molecular weights of organic molecules. The rDUVLAESCI benefits from the coupling of a 193 nm Analyte G2 laser ablation unit (Photon Machines) with a hybrid Q-TOF mass spectrometer Synapt G2S (Waters), enabling the simultaneous acquisition of complementary ESI and APCI mass spectra in a single analytical run. Using r-DUV-LAESCI-MS/MSI, suitable ionization conditions were optimized by testing various flow rates and types of sheath liquids in the dual ion source (ESCI), as well as evaluating the effects of different surface materials on signal intensities for various analytes. The applicability of rDUVLAESCI in molecular MSI was demonstrated on analysis and imaging of molecules directly in thin mouse brain tissue sections (12-30 µm thick). The main molecules detected were cholesterol and its derivatives (dehydrocholesterol, oxocholesterol, and desmosterol), free fatty acids (palmitic acid, linolenic acid), sphingosine, diacylglycerols (mainly dipalmitoyl glycerol), phospholipids, and C18 ceramide and adenine.

* Korespondující autor: tomas.pluhacek@upol.cz

Literatura

1. A. Venter, M. Nefliu, R. Graham Cooks, TrAC Trends Anal. Chem., 27, 284−290, 2008.
2. B. Papoušková, P. Fryčák, F. Gregar, K. Lemr, T. Pluháček. Anal. Chem., 97, 2062-2069, 2025.

Poděkování:

The research was funded by Internal Grant Agency, Palacky University Olomouc (IGA_PrF_2024_027).