Used as a key reagent in bioconjugation and chemical biology, particularly in click chemistry reactions. The azide group readily participates in copper-catalyzed azide-alkyne cycloaddition (CuAAC), enabling efficient labeling and attachment of biomolecules such as peptides, proteins, and nucleic acids to fluorescent tags, polymers, or solid supports. Its primary amine group, protected as the hydrochloride salt, can be selectively deprotected and further functionalized, allowing for orthogonal conjugation strategies. Commonly employed in the synthesis of probes for imaging, drug delivery systems, and surface modification of nanomaterials. Also utilized in the development of bioactive molecule libraries through combinatorial chemistry.