MS imaging technology initially appeared in the first half of
the 1980s and has continued to undergo technological
innovation to the present day. It is used in a wide variety of
fields including drug discovery and metabolomics research.
Technological improvements are still being pursued to this
day to enhance capabilities including sensitivity, spatial
resolution, and repeatability.
Although various matrices that employ ionization have been
developed over the years, it is important to select the matrix
appropriate for the targeted compound.
In addition to matrix selection, the coating method also has a
significant effect on analysis results. Consequently, a number of
coating methods appropriate for the targeted compound have
been examined. These are broadly divided into the spray
method and the sublimation method, and since each method
has its advantages and disadvantages, currently both are
widely used. Shimadzu has developed the iMLayer matrix
vapor deposition system employing the sublimation method
(Fig. 1), which can control the matrix coating thickness. Matrix
coating methods have been further examined using this
This article introduces a sublimation/recrystallization method we developed for 9AA, with which recrystallization was previously said to be difficult. Examples of MS imaging using this method are also introduced for low low molecular weight
metabolites (LMWMs) in a mouse liver.