Mass spectrometry imaging and profiling of indi
vidual cells and subcellular structures pro
vide unique analytical capabilities for biological and biomedical research, including determination of the biochemical heterogeneity of cellular populations and intracellular localization of pharmaceuticals. Two mass spectrometry technologies-secondary ion mass spectrometry (SIMS) and matrix assisted laser desorption/ionization mass spectrometry (MALDI MS)-are most often used in micro-bioanalytical in
vestigations. Recent ad
vances in ion probe technologies ha
ve increased the dynamic range and sensiti
vity of analyte detection by SIMS, allowing two- and three-dimensional localization of analytes in a
variety of cells. SIMS operating in the mass spectrometry imaging (MSI) mode can routinely reach spatial resolutions at the submicron le
vel; therefore, it is frequently used in studies of the chemical composition of subcellular structures. MALDI MS offers a large mass range and high sensiti
vity of analyte detection. It has been successfully applied in a
variety of single-cell and organelle profiling studies. Inno
vati
ve instrumentation such as scanning microprobe MALDI and mass microscope spectrometers enables new subcellular MSI measurements. Other approaches for MS-based chemical imaging and profiling include those based on near-field laser ablation and inducti
vely-coupled plasma MS analysis, which offer complementary capabilities for subcellular chemical imaging and profiling.
This article is part of a Special Issue entitled: Imaging Mass Spectrometry: A User¡¯s Guide to a New Technique for Biological and Biomedical Research.