Capillary Electrophoresis-Mass Spectrometry for Peptide Analysis: Target-Based Approaches and Proteomics/Peptidomics Strategies

In this chapter, the potential of capillary electrophoresis-mass spectrometry (CE-MS) for peptide analysis is demonstratedby the presentation of two different strategies typically followed in analysis of these biomolecules by CE-MS. The first oneis a target-based approach and it is used to detect a toxic oligopeptide in a complex matrix. Namely, CE-MS using an ion trapMS analyzer is applied to detect and quantify γ-glutamyl-
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-ethenyl-cysteine (GEC) bioactive dipeptide in a legume plant. The second one is a shotgun-like methodology used for proteomicanalysis. Particularly, CE-MS using a time-of-flight MS analyzer is employed to investigate the substantial equivalence betweena genetically modified (GM) variety of soybean and its conventional isogenic counterpart. These generic methods have broadapplications for the analysis of peptides in a large variety of matrices, including applications in the area of proteomicsand peptidomics.