TY  - JOUR
AU  - Sidorov, Iulia
AU  - Ogrinc, Nina
AU  - Spieth, Lena
AU  - Kopcil, Michal
AU  - Heijink, Marieke
AU  - Dalebout, Hans
AU  - Saher, Gesine
AU  - Berghoff, Stefan A
AU  - Siuzdak, Gary
AU  - Giera, Martin
TI  - In-Source Fragmentation Annotation in Sterol Mass Spectrometry Imaging.
JO  - Analytical chemistry
VL  - 98
IS  - 1
SN  - 0003-2700
CY  - Columbus, Ohio
PB  - American Chemical Society
M1  - DZNE-2026-00069
SP  - 509 - 518
PY  - 2026
AB  - Spatial biology has emerged as a pivotal area in many life science fields, with mass spectrometry imaging (MSI) becoming a cornerstone for molecular imaging. Among recent advancements to increase sensitivity, MALDI-2 technology has significantly expanded the molecular space accessible to MSI, increasing the ion yields of neutral metabolites, such as sterols. Sterols have recently taken center stage in numerous (patho-) physiological processes, including neurodegenerative diseases that have attracted significant scientific interest. However, in-source fragmentation (ISF) poses a substantial challenge for accurate biological interpretation of mass spectrometric data. In this study, we observed and investigated the ISF of cholesterol during MSI under MALDI and MALDI-2 conditions. Using a murine intervention model, we demonstrate how ISF can compromise the accuracy of biological interpretations, potentially leading to significant misinterpretations. Our study underscores the critical need to address ISF to ensure accurate molecular annotation, particularly through tandem mass spectrometry of in-source fragments. This is especially important when using MALDI-2 techniques. Furthermore, we introduce a high-resolution (5 μm) MSI technique, enabling the precise spatial analysis of cholesterol distribution.
KW  - Animals
KW  - Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization: methods
KW  - Mice
KW  - Cholesterol: analysis
KW  - Cholesterol: metabolism
KW  - Sterols: analysis
KW  - Sterols: chemistry
KW  - Molecular Imaging: methods
KW  - Cholesterol (NLM Chemicals)
KW  - Sterols (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:41408757
DO  - DOI:10.1021/acs.analchem.5c05199
UR  - https://pub.dzne.de/record/283220
ER  -