Fundamentals of Mass Spectrometry-Based Metabolomics

Metabolomics involves the study of a complex and diverse array of compounds that can be thought of as the ultimate end products of the complex systems that are characteristic of molecular biology. The compounds that constitute the metabolome are small in size relative to the genome and proteome and include amino acids, carbohydrates, organic acids, lipids, and nucleotides with a mass less than 1800 Da. Understanding the role of these metabolites and the way in which changes in these important molecules impact biological processes has great potential to improve public health through better understanding of disease mechanisms. A comprehensive understanding of the metabolome will ultimately lead to better candidate biomarkers and drug targets enabling improvements in patient care. Metabolomics experiments can be divided primarily into two experimental strategies: targeted and untargeted. This monograph details these two approaches and the specific considerations for sample preparation, analytical separations, instrumental considerations, and data analysis that are required in the practice of these important technologies. Furthermore, selected applications of targeted and untargeted experiments are showcased to demonstrate the role of metabolomics as part of multi-omics studies and how metabolites can be spatially mapped in biological systems using imaging mass spectrometry.