title: Nanostructured indium tin oxide slides for small-molecule profiling and imaging mass spectrometry of metabolites by surface-assisted laser desorption ionization MS.
abstract: Due to their electrical conductivity and optical transparency, slides coated with a thin layer of indium tin oxide (ITO) are the standard substrate for protein imaging mass spectrometry on tissue samples by MALDI-TOF MS. We have now studied the rf magnetron sputtering deposition parameters to prepare ITO thin films on glass substrates with the required nanometric surface structure for their use in the matrix-free imaging of metabolites and small-molecule drugs, without affecting the transparency required for classical histology. The custom-made surfaces were characterized by atomic force microscopy, scanning electron microscopy, ellipsometry, UV, and laser desorption ionization MS (LDI-MS) and employed for the LDI-MS-based analysis of glycans and druglike molecules, the quantification of lactose in milk by isotopic dilution, and metabolite imaging on mouse brain tissue samples.
authors.affiliation: Glycotechnology Laboratory, ‡Surface Analysis and Fabrication Platform, §Mass Spectrometry Platform, and ∥Radiochemistry Laboratory, CIC biomaGUNE , Paseo Miramon 182, 20009 San Sebastian, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: López de Laorden
authors.forename: Ana
authors.initials: A
authors.lastname: Beloqui
authors.forename: Luis
authors.initials: L
authors.lastname: Yate
authors.forename: Javier
authors.initials: J
authors.lastname: Calvo
authors.forename: Maria
authors.initials: M
authors.lastname: Puigivila
authors.forename: Jordi
authors.initials: J
authors.lastname: Llop
authors.forename: Niels-Christian
authors.initials: NC
authors.lastname: Reichardt
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007553:Isotope Labeling; D007785:Lactose / Q000032:analysis; D007834:Lasers; D055432:Metabolomics; D051379:Mice; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D008892:Milk / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D004364:Pharmaceutical Preparations / Q000032:analysis; D056951:Photoelectron Spectroscopy; D011134:Polysaccharides / Q000032:analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D017971:Tin Compounds / Q000737:chemistry*
chemical_list: D004364:Pharmaceutical Preparations; D011134:Polysaccharides; D017971:Tin Compounds; C109984:indium tin oxide; D007785:Lactose