Application of Matrix-Assisted Laser Desorption/Ionization Imaging Mass Spectrometry

The clarification of metabolic dynamics in lesion areas is important. Many approaches, such as high performance liquid chromatography mass spectrometry, gas chromatography mass spectrometry, immunohistochemistry, are used to define disease-related abnormalities. Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is attracting attention as a new valuable tool. MALDI-IMS is a two-dimensional MALDI mass spectrometric technique used to visualize the spatial distribution of molecules without extraction, purification, separation, or labeling of biological samples (Cornett et al., 2007; Zaima et al., 2010b). MALDI-IMS has revealed the characteristic distribution of several biomolecules, including proteins (Caprioli et al., 1997; Groseclose et al., 2007; Morita et al., 2010), peptides (Chansela et al., 2011; Stoeckli et al., 2002), amino acids (Goto-Inoue et al., 2010b; Zaima et al., 2010a), lipids (Hayasaka et al., 2009; Murphy et al., 2009; Zaima et al., 2011a), and carbohydrates (Goto-Inoue et al., 2010b), in various tissues. The versatility of MALDI-IMS has opened a new frontier in several fields, such as pharmacology, medicine, agriculture, biology, and pathology. In this review, we describe the methodology and applications of MALDI-IMS for biological samples.