Laser Desorption/Ionization Mass Spectrometric Imaging of Endogenous Lipids from Rat Brain Tissue Implanted with Silver Nanoparticles

• Published in: Journal of the American Society for Mass Spectrometry Vol. 28; no. 8; pp. 1716 - 1728
• Main Authors: Muller, Ludovic, Baldwin, Kathrine, Barbacci, Damon C., Jackson, Shelley N., Roux, Aurélie, Balaban, Carey D., Brinson, Bruce E., McCully, Michael I., Lewis, Ernest K., Schultz, J. Albert, Woods, Amina S.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2017; Springer Nature B.V
• Subjects: Analytical Chemistry; ANIMAL TISSUES; Animals; ANIONS; Bioinformatics; Biotechnology; Brain; Brain Chemistry; Cations; Chemistry; Chemistry and Materials Science; CHOLESTEROL; DESORPTION; Fatty acids; FRAGMENTATION; Image quality; Implantation; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; IONIZATION; Ions; LASERS; LECITHINS; Lipids; Lipids - analysis; Male; Mass spectrometry; MASS SPECTROSCOPY; Metal Nanoparticles - analysis; NANOPARTICLES; NANOSCIENCE AND NANOTECHNOLOGY; Organic Chemistry; Proteomics; Rats; Rats, Sprague-Dawley; Reproducibility; Research Article; SILVER; Silver - analysis; Soft landing; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Nanoparticles; Silver; Lipids; Mass spectrometry imaging
• ISSN: 1044-0305; 1879-1123
• DOI: 10.1007/s13361-017-1665-4

Mass spectrometry imaging (MSI) of tissue implanted with silver nanoparticulate (AgNP) matrix generates reproducible imaging of lipids in rodent models of disease and injury. Gas-phase production and acceleration of size-selected 8 nm AgNP is followed by controlled ion beam rastering and soft landing implantation of 500 eV AgNP into tissue. Focused 337 nm laser desorption produces high quality images for most lipid classes in rat brain tissue (in positive mode: galactoceramides, diacylglycerols, ceramides, phosphatidylcholines, cholesteryl ester, and cholesterol, and in negative ion mode: phosphatidylethanolamides, sulfatides, phosphatidylinositol, and sphingomyelins). Image reproducibility in serial sections of brain tissue is achieved within <10% tolerance by selecting argentated instead of alkali cationized ions. The imaging of brain tissues spotted with pure standards was used to demonstrate that Ag cationized ceramide and diacylglycerol ions are from intact, endogenous species. In contrast, almost all Ag cationized fatty acid ions are a result of fragmentations of numerous lipid types having the fatty acid as a subunit. Almost no argentated intact fatty acid ions come from the pure fatty acid standard on tissue. Graphical Abstract ᅟ