抄録
Mass microprobe acquires mass-to-charge ratios of ions which are generated at an extremely small area on the sample surface. A raster achieved by moving the area of ionization over the sample surface allows to map a wide variety of compounds existing on the surface with a lateral resolution of 1-100 μm. The technology to visualize a local distribution of compounds in the sample is called imaging mass spectrometry and is recognized as an emerging field of mass spectrometry in recent years. Mass microprobe can now be applied to biological samples, such as thin tissue sections, after significant progress of sample preparation techniques. SIMS, LDI, and MALDI are ionization methods utilized in mass microprobe. Molecular images of light compounds, such as lipids or metabolites, are suited to be recorded by SIMS or LDI, whereas peptides and proteins are targeted by MALDI. Although the sensitivity is the most important issue still to be overcome, mass microprobe is superior to optical observations for providing chemical information on biological samples, and is highly promising as a practical tool of biological researches in very near future.
