Funnel-freezing versus heat-stabilization for the visualization of metabolites by mass spectrometry imaging in a mouse stroke model

Proteomics. 2016 Jun;16(11-12):1652-9. doi: 10.1002/pmic.201500402. Epub 2016 May 9.


Tissue preparation is the key to a successful matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) experiment. Rapid post-mortem changes contribute a significant challenge to the use of MSI approaches for the analysis of peptides and metabolites. In this technical note we aimed to compare the tissue fixation method ex-vivo heat-stabilization with in-situ funnel-freezing in a middle cerebral artery occlusion (MCAo) mouse model of stroke, which causes profound alterations in metabolite concentrations. The influence of the duration of the thaw-mounting of the tissue sections on metabolite stability was also determined. We demonstrate improved stability and biomolecule visualization when funnel-freezing was used to sacrifice the mouse compared with heat-stabilization. Results were further improved when funnel-freezing was combined with fast thaw-mounting of the brain sections.

Keywords: Funnel-freezing; Heat-stabilization; Ischemic stroke; MALDI-MSI; Metabolites; Technology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / metabolism*
  • Brain / pathology
  • Disease Models, Animal
  • Freezing
  • Hot Temperature
  • Humans
  • Infarction, Middle Cerebral Artery / diagnostic imaging*
  • Infarction, Middle Cerebral Artery / pathology
  • Mice
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods*
  • Stroke / diagnosis
  • Stroke / diagnostic imaging*
  • Stroke / pathology