posted on 2023-07-10, 04:54authored byNigina Khamidova, Melissa R. Pergande, Koralege C. Pathmasiri, Rida Khan, Justin T. Mohr, Stephanie M. Cologna
MALDI-TOF MS is a powerful tool to analyze biomolecules,
owing
to its soft ionization nature that generally results in simple spectra
of singly charged ions. Implementation of the technology in the imaging
mode provides a means to spatially map analytes in situ. Recently,
a new matrix, DBDA (N1,N4-dibenzylidenebenzene-1,4-diamine)
was reported to facilitate the ionization of free fatty acids in
negative ion mode. Building on this finding, we sought to implement
DBDA for MALDI mass spectrometry imaging studies in brain tissue and
successfully map oleic acid, palmitic acid, stearic acid, docosahexaenoic
acid, and arachidonic acid using mouse brain sections. Moreover, we
hypothesized that DBDA would provide superior ionization for sulfatides,
a class of sulfolipids with multiple biological functions. Herein,
we also demonstrate that DBDA is ideal for MALDI mass spectrometry
imaging of fatty acids and sulfatides in brain tissue sections. Additionally,
we show enhanced ionization of sulfatides using DBDA compared with
three different traditionally used MALDI matrices. Together these
results provide new opportunities for studies to measure sulfatides
by MALDI-TOF MS.