Abstract

Mass spectrometry imaging (MSI) is applied to measure the spatial distribution of hundreds of biomolecules in a sample. A mass spectrometer scans over the entire sample and collects a mass spectrum every 5-200 µm. This results in thousands of spots (or pixels) for each of which a mass spectrum is acquired. Each mass spectrum consists of hundreds of analytes that are measured by their mass-to-charge (m/z) ratio. For each analyte the peak intensity in the mass spectra of every pixel is known and can be set together to map the spatial distribution of the analyte in the sample.

About This Material

This is a Hands-on Tutorial from the GTN which is usable either for individual self-study, or as a teaching material in a classroom.

Questions this will address

• Can N-linked glycans from FFPE tissues be detected by MALDI imaging?
• Can potential N-linked glycans be identified by an additional LC-MS/MS experiment?
• Do specific kidney compartments have different N-linked glycan compositions?

Learning Objectives

• Combining MSI datasets while using the information about each subfile in further steps.
• Preprocessing raw MSI data.
• Performing supervised and unsupervised statistical analysis.