Stable isotope-resolved metabolomics based on mass spectrometry: Methods and their applications

The introduction of stable isotope labeling (SIL) technology into metabolomics can provide insight into the "dynamic" metabolic regulation in organisms and has recently become a routine tool for functional metabolomics studies. Mass spectrometry (MS) techniques have shown great vitality in this field by utilizing similar different mass spectrometric characteristics between endogenous metabolites and their isotope-labeling forms. In recent years, MS-based stable isotope-resolved metabolomics (SIRM) methods have made great progress in sample pretreatment, MS analysis and data analysis to further expand the breadth and depth of SIRM research. In this review, the recent progresses of SIRM methods are described. Their applications in metabolite identification, accurate quantification and metabolic flux analysis are also summed up, and current limitations and challenges are discussed.