title: Imaging MALDI mass spectrometry of sphingolipids using an oscillating capillary nebulizer matrix application system.
abstract: Matrix deposition is a critical step in tissue imaging by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). It greatly affects the quality of MALDI imaging, especially for the analytes (such as lipids) that may easily dissolve in the solvent used for the matrix application. This chapter describes the use of an oscillating capillary nebulizer (OCN) to spray small droplets of matrix aerosol onto the sample surface for improved matrix homogeneity, reduced crystal size, and controlled solvent effects. This protocol allows visualization of many different lipid species and, of particular interest, sphingolipids in tissue slices of Tay-Sachs/Sandhoff disease by imaging MALDI-MS. The structures of these lipids were identified by analysis of tissue extracts using electrospray ionization in conjunction with tandem mass spectrometry (MS/MS and MS(3)). These results illustrate the usefulness of tissue imaging MALDI-MS with matrix deposition by OCN for the molecular analysis in normal physiology and pathology. In addition, the observation of numerous lipid subclasses with distinct localizations in the brain slices demonstrates that imaging MALDI-MS could be effectively used for "lipidomic" studies.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Chen
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Jeremy
authors.initials: J
authors.lastname: Allegood
authors.forename: Elaine
authors.initials: E
authors.lastname: Wang
authors.forename: Begoña
authors.initials: B
authors.lastname: Cachón-González
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Cox
authors.forename: Alfred H
authors.initials: AH
authors.lastname: Merrill
authors.forename: M Cameron
authors.initials: MC
authors.lastname: Sullards
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging / Q000379:methods*; D051379:Mice; D008817:Mice, Mutant Strains; D008855:Microscopy, Electron, Scanning; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013107:Sphingolipids / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D013107:Sphingolipids