Abstract: The invention relates to the analysis of carbohydrates, such as N-glycans and O-glycans found on proteins. The invention relates, in part, to glycan labeling with formulas/compounds enhancing their detection and/or analysis by methods such as capillary electrophoresis, liquid chromatography and mass spectrometry. These detection methods may be useful in studying glycosylation patterns of biological or medical samples, or for assessing protein production, protein quality/purity, for comparing innovator and biosimilar glycosylated proteins, or for selecting proteins with the desired glycosylation.