UDP-GalNAz.2Na is widely used in glycobiology research for the study of glycoproteins and glycosylation processes. It serves as a key substrate for enzymatic labeling of glycans, enabling the incorporation of azide-functionalized GalNAc (N-azidoacetylgalactosamine) into cellular glycoconjugates. This azide group can then be selectively modified using bioorthogonal reactions, such as click chemistry, for imaging, detection, or purification purposes. It is particularly valuable in metabolic oligosaccharide engineering, where it helps track and analyze glycan dynamics in live cells or tissues. Additionally, it aids in the development of glycoprotein-based therapeutics and vaccines by facilitating the precise modification and characterization of glycosylation patterns. Its applications extend to cancer research, where it helps identify glycosylation changes associated with tumor progression.