Biotium offers reactive biotin compounds with a variety of reactive functional groups.

• Reagents for biotinylation of proteins and other biomolecules
• Full selection of reactive functional groups
• Variety of linker lengths available for improved water solubility and streptavidin binding

Amine reactive:
Succinimidyl esters react with primary and secondary amines and can be used to label proteins or peptides

Thiol reactive:
Maleimide and iodoacetamide react with thiol groups
MTSEA selectively labels thiols under mild conditions
TS biotin compounds allow selective labeling of cell surface thiols

Other reactive chemistries:
Amine groups can be reacted with activated carboxylic acids
Cadaverine can be coupled to carboxylic acids, DNA, and other biomolecules
Cadaverine free base can be directly coupled to activated carboxylic acids without the use of additional base
Hydrazides react with aldehydes or ketones to form unstable hydrazone linkages
Aminooxy reacts with aldehydes or ketones to form stable oxime bonds, and may be preferable to hydrazides for labeling
Tyramides can be used for HRP-mediated tyramide signal amplification (TSA) reactions
Alkynes react with azides by copper(I)-catalyzed 1,3-dipolar Huisgen cycloaddition
BCN groups react with azides by copper-free 1,3-dipolar Huisgen cycloaddition

Non-reactive free acid forms:
Biotin-X free acid (6-((Biotinoyl)amino)hexanoic acid) can be easily converted to the mixed anhydride form, which is more reactive than the succinimidyl ester and thus can be used to react with aromatic amines or sterically hindered amines.
Biotin-XX free acid (6-((6-((Biotinoyl)amino)hexanoyl)amino)hexanoic acid) can be easily converted to the mixed anhydride form, which is more reactive than the succinimidyl ester and thus can be used to react with aromatic amines or sterically hindered amines.

Note: A full range of fluorescent CF™ Dyes are also available.