Gustafsson, O.Eddes, J.Meding, S.McColl, S.Oehler, M.Hoffmann, P.2013-06-172013-06-172013Rapid Communications in Mass Spectrometry, 2013; 27(6):655-6700951-41981097-0231http://hdl.handle.net/2440/78386<h4>Rationale</h4>Matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry provides the means to map the in situ distribution of tryptic peptides in formalin-fixed clinical tissue samples. The ability to analyze clinical samples is of great importance to further developments in the imaging field. However, there is a requirement in this field of research for additional methods describing the characterization of tryptic peptides by MALDI imaging.<h4>Methods and results</h4>This protocol gives highly detailed instructions, with examples, for (1) successfully performing tryptic peptide MALDI imaging on formalin-fixed cancer tissue using a MALDI-TOF/TOF MS instrument, (2) tentatively generating identifications through nLC/MS/MS, and (3) validating these identifications by in situ MS/MS of peptides of interest.<h4>Conclusions</h4>This protocol provides a detailed and straightforward description of the methods required for groups new to MALDI imaging to begin analysis of formalin-fixed clinical samples.enCopyright © 2013 John Wiley & Sons, Ltd.HumansNeoplasmsFormaldehydeTrypsinPeptide FragmentsCalibrationSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationHistocytological Preparation TechniquesAmino Acid SequenceImage Processing, Computer-AssistedMolecular Sequence DataTandem Mass SpectrometryMolecular ImagingJournal article002012563710.1002/rcm.64880003151091000012-s2.0-8487405133521180McColl, S. [0000-0003-0949-4660]Oehler, M. [0000-0002-2651-5913]