title: Optimized Mass Spectrometry Analysis Workflow with Polarimetric Guidance for ex vivo and in situ Sampling of Biological Tissues.
abstract: Spatially Targeted Mass Spectrometry (MS) analysis using survey scans with an imaging modality often requires consecutive tissue slices, because of the tissue damage during survey scan or due to incompatible sample preparation requirements between the survey modality and MS. We report two spatially targeted MS analysis workflows based on polarized light imaging guidance that use the same tissue sample for survey and targeted analysis. The first workflow is applicable for thin-slice analysis, and uses transmission-polarimetry-guided Desorption ElectroSpray Ionization Mass Spectrometry (DESI-MS), and confirmatory H&E histopathology analysis on the same slice; this is validated using quantitative digital pathology methods. The second workflow explores a polarimetry-guided MS platform for thick tissue assessment by developing reflection-mode polarimetric imaging coupled with a hand-held Picosecond InfraRed Laser (PIRL) MS ablation probe that requires minimal tissue removal to produce detectable signal. Tissue differentiation within 5-10 s of sampling with the hand-held probe is shown using multivariate statistical methods of the MS profiles. Both workflows were tasked with differentiating necrotic cancer sites from viable cancers using a breast tumour model, and their performance was evaluated. The use of the same tissue surface addresses mismatches in guidance due to intrinsic changes in tissue morphology over consecutive sections.
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada.|Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Woolman
authors.affiliation: Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada.
authors.forename: Adam
authors.initials: A
authors.lastname: Gribble
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada.
authors.forename: Emma
authors.initials: E
authors.lastname: Bluemke
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada.
authors.forename: Jing
authors.initials: J
authors.lastname: Zou
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada.
authors.forename: Manuela
authors.initials: M
authors.lastname: Ventura
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Bernards
authors.affiliation: Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, Toronto, ON, M5G-0A4, Canada.
authors.forename: Megan
authors.initials: M
authors.lastname: Wu
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada.|Department of Surgery, University of Toronto, 149 College Street, Toronto, ON, M5T-1P5, Canada.|Keenan Research Center for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B-1W8, Canada.|Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON, M5S 3G9, Canada.
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Ginsberg
authors.affiliation: Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, Toronto, ON, M5G-0A4, Canada.|Department of Surgery, University of Toronto, 149 College Street, Toronto, ON, M5T-1P5, Canada.|Keenan Research Center for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B-1W8, Canada.
authors.forename: Sunit
authors.identifier: 0000-0002-2146-4168
authors.initials: S
authors.lastname: Das
authors.affiliation: Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, Toronto, ON, M5G-0A4, Canada.|Department of Radiation Oncology, University of Toronto, 610 University Avenue, Toronto, Ontario, M5G 2M9, Canada.|Division of Biophysics and Bioimaging, Ontario Cancer Institute, University Health Network, 610 University Ave, Toronto, ON, M5G 2M9, Canada.
authors.forename: Alex
authors.initials: A
authors.lastname: Vitkin
authors.affiliation: Techna Institute for the Advancement of Technology for Health, University Health Network, Toronto, ON, M5G-1P5, Canada. arash.zarrine.afsar@utoronto.ca.|Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada. arash.zarrine.afsar@utoronto.ca.|Department of Surgery, University of Toronto, 149 College Street, Toronto, ON, M5T-1P5, Canada. arash.zarrine.afsar@utoronto.ca.|Keenan Research Center for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B-1W8, Canada. arash.zarrine.afsar@utoronto.ca.
authors.forename: Arash
authors.initials: A
authors.lastname: Zarrine-Afsar
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging / Q000379:methods; D006651:Histocytochemistry / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D013058:Mass Spectrometry / Q000379:methods; D051379:Mice; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D057188:Workflow