Matrix-assisted laser desorption–ionization (MALDI) imaging mass spectrometry allows direct, in situ, label-free measurement of proteins, peptides, lipids, small-molecule drugs and their metabolites, and other chemicals in tissues. In a range of applications, the unique information generated by MALDI imaging can make a significant contribution to understanding factors such as molecular and metabolic mechanisms and the transport and localization of compounds or metabolites with human, animal, or plant species.
