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Study of glycomes
Glycomics is the comprehensive study of glycomes (the entire complement of sugars, whether free or present in more complex molecules of an organism), including genetic, physiologic, pathologic, and other aspects. Glycomics "is the systematic study of all glycan structures of a given cell type or organism" and is a subset of glycobiology. The term glycomics is derived from the chemical prefix for sweetness or a sugar, "glyco ", and was formed to follow the omics naming convention established by genomics (which deals with genes) and proteomics (which deals with proteins).

The following are examples of the commonly used techniques in glycan analysis In case of glycolipids, they can be analyzed directly without separation of the lipid component. N glycans from glycoproteins are analyzed routinely by high performance liquid chromatography (reversed phase, normal phase and ion exchange HPLC) after tagging the reducing end of the sugars with a fluorescent compound (reductive labeling). A large variety of different labels were introduced in the recent years, where 2 aminobenzamide (AB), anthranilic acid (AA), 2 aminopyridin (PA), 2 aminoacridone (AMAC) and 3 (acetylamino) 6 aminoacridine (AA Ac) are just a few of them. O glycans are usually analysed without any tags, due to the chemical release conditions preventing them to be labeled. Fractionated glycans from high performance liquid chromatography (HPLC) instruments can be further analyzed by MALDI TOF MS(MS) to get further information about structure and purity. Sometimes glycan pools are analyzed directly by mass spectrometry without prefractionation, although a discrimination between isobaric glycan structures is more challenging or even not always possible. Anyway, direct MALDI TOF MS analysis can lead to a fast and straightforward illustration of the glycan pool. In recent years, high performance liquid chromatography online coupled to mass spectrometry became very popular. By choosing porous graphitic carbon as a stationary phase for liquid chromatography, even non derivatized glycans can be analyzed. Electrospray ionisation (ESI) is frequently used for this application.

Lectin and antibody arrays provide high throughput screening of many samples containing glycans. This method uses either naturally occurring lectins or artificial monoclonal antibodies, where both are immobilized on a certain chip and incubated with a fluorescent glycoprotein sample. Glycan arrays, like that offered by the Consortium for Functional Glycomics and Z Biotech LLC, contain carbohydrate compounds that can be screened with lectins or antibodies to define carbohydrate specificity and identify ligands.

Metabolic labeling of glycans can be used as a way to detect glycan structures. A well known strategy involves the use of azide labeled sugars which can be reacted using the Staudinger ligation. This method has been used for in vitro and in vivo imaging of glycans.

X ray crystallography and nuclear magnetic resonance (NMR) spectroscopy for complete structural analysis of complex glycans is a difficult and complex field. However, the structure of the binding site of numerous lectins, enzymes and other carbohydrate binding proteins has revealed a wide variety of the structural basis for glycome function. The purity of test samples have been obtained through chromatography (affinity chromatography etc.) and analytical electrophoresis (PAGE (polyacrylamide electrophoresis), capillary electrophoresis, affinity electrophoresis, etc. ).