DBCO-PEG4-Biotin (CAS 1255942-07-4)

The azadibenzocyclooctyne-biotin derivative is designed for efficient labeling of azide-containing molecules or compounds. By employing strain-promoted copper-free azide-alkyne cycloaddition reactions, cyclooctynes play a role in this process. This particular dibenzocyclooctyne derivative facilitates the reaction with azide-functionalized compounds or biomolecules without the need for a Cu(I) catalyst, resulting in the formation of a stable triazole linkage. Subsequent labeled molecules can be easily purified using streptavidin or avidin affinity reagents. With the inclusion of a PEG spacer, the overall compound becomes more hydrophilic, allowing for increased distance between the reaction site and the biotin detecting group. DBCO-PEG4-Biotin is a PEG derivative that incorporates both a biotin group and an alkyne group. The alkyne group readily reacts with azide moieties in copper-free Chemistry reactions, forming a stable triazole linkage. The presence of a hydrophilic PEG spacer enhances solubility in aqueous media and increases the impermeability of the molecules conjugated to the biotin compound, thus aiding in their isolation. Furthermore, the PEG spacer helps minimize steric hindrance during binding to avidin molecules.