Profiling of primary metabolite by means of capillary electrophoresis-mass spectrometry and its application for plant science

Metabolites in primary metabolic pathways, such as glycolysis, the tricarboxylic acid cycle, the pentose phosphate pathway, the Calvin cycle and amino acid biosynthetic pathways, are ionic compounds. It is difficult to analyze these metabolites simultaneously by established methods for metabolite profiling of biological samples such as gas chromatography-mass spectrometry or liquid chromatography-mass spectrometry. Capillary electrophoresis-mass spectrometry (CE-MS) is a promising method for the comprehensive and quantitative analysis of ionic metabolites. This technique enables the simultaneous determination of over 1000 charged compounds. This review discusses the principles and practical procedures for conducting CE-MS, describes specific applications of CE-MS for primary metabolite profiling, and enumerates some of the technical problems associated with CE-MS at present.