MALDI-MS is a powerful tool for analyzing a variety of different analytes including small molecules (metabolites), lipids, nucleic acids, peptides, proteins, and polymers ranging in molecular mass from 100 Da up to 100 kDa or more. For analysis by MALDI, a sample is mixed or coated with an energy-absorbing matrix and then irradiated with a laser beam (typically a Nd:Yag laser). Singly protonated (positive ionization mode) or deprotonated (negative ionization mode) molecular ions are formed and detected by a time-of-flight mass analyzer. the 5800 TOF/TOF that resides in the Mass Spectrometry Laboratory is also capable of MALDI Imaging Mass Spectrometry (MALDI IMS). MALDI IMS is accomplished by acquiring mass spectra across material or tissue areas. A two-dimensional optical image of each material slice reveals the spatial distribution of chemicals on that slice to 10-50 μm resolution. A user can then select mass values for compounds of interest and “stain” the image with mass-specific colors. Each pixel on the color-coded image contains a detailed mass spectral analysis of compounds localized at that spot.