Biotin-LC-LC-NHS is a useful reagent for biotinylation of primary amines under mild conditions (pH~6.5-8.5). Some examples of primary amines for biotinylation include lysines on the surface of proteins, antibodies, etc. Inserts a 14-atom spacer between biotin and the target ligand, thus minimizing the steric hindrance in binding avidin or streptavidin to some biotinylated compounds and increase sensitivity for detection.