Isotope labeling strategies of glycans for mass spectrometry-based quantitative glycomics

[Display omitted] Robust mass spectrometry-based methods for quantitative glycomics are almost invariable based on stable isotope labeling. These approaches represent a mature and yet evolving array of techniques that enable high-accuracy, high-speed, high-sensitivity, and high-throughput analysis of glycans from diverse biological matrices. The introduction of stable isotopes into biomolecules can be accomplished by three major ways, namely by metabolic, enzymatic, and chemical labeling of samples. Together, these approaches cover a wide variety of potential sample types, including purified glycans, cell and tissue samples, as well as clinical specimens. In this review, various aspects of isotope labeling strategies in comparative glycomics are discussed.