Imaging mass spectrometry: viewing the future.

Imaging mass spectrometry (IMS) technology is an effective tool that is able to assess complex molecular mixtures in cells, tissues, or other sample types with high chemical specificity, allowing concurrent analysis of a variety of molecular species in a wide mass range, from small metabolites to large macromolecules such as proteins. Simultaneous localization of molecules, detection of post-translational modifications, and relative quantitative information can be obtained in a single experiment. Images generated by MS are unique because they are derived from direct molecular measurements and do not rely on target-specific reagents such as antibodies. Thus, the ability to map spatial distributions coupled with the mass accuracy and chemical specificity for MS-based detection makes IMS an effective discovery tool. Further structural assessment of compounds, including MS/MS fragmentation analysis, can be utilized in an imaging experiment to achieve accurate molecular identifications.