Mass Spectrometry Imaging

Mass spectrometry imaging (MSI) is a technique used for mapping the spatial distributions of molecular species across a sample. Thousands of analytes including metabolites, lipids, peptides, proteins and glycans can be visualized and spatially resolved without the need for labeling. Thus, MSI is a versatile technology that is used for a wide range of applications including clinical diagnostics and pathology, food science, forensics, natural products, pharmaceutical R&D, plant sciences, spatial lipidomics and metabolomics and whole-body analyses. Molecular information obtained from MSI can be overlaid with other imaging modalities such as histology to correlate molecular profiles to tissue substructures or other features. In METRIC, MSI is performed using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) and a high resolving power mass spectrometer for accurate mass measurements. MSiReader software, developed at NC State as a free, open-source, vendor-neutral platform built using Matlab is the foundation for our data analysis pipeline.