The use of biotin for non-radioactive labeling of proteins and nucleic acids has now become an increasingly popular technique in life science research

G-Biosciences' HOOK™ Carbohydrate Reactive Biotin Reagents react with oxidized carbohydrate side chains. Some biotin reagents do not bind directly to the protein itself, but instead, conjugate to the carbohydrate residues of glycoproteins. The carbohydrate reactive biotin reagents contain hydrazides (-NH-NH₂) as a reactive group. The hydrazide reactions require carbonyl groups, such as aldehydes and ketones, which are formed by oxidative treatment of the carbohydrates. Hydrazides react spontaneously with carbonyl groups, forming a stable hydrazone bond. These reagents are particularly suitable for labeling and studying glycosylated proteins, such as antibodies and receptors. HOOK™-Biotin-Hydrazide and its long spacer arm equivalent, HOOK™-Biotin-LC-Hydrazide, are carbohydrate reactive reagents.

G-Biosciences' HOOK™ Carbohydrate Reactive Biotin Reagents are each available as the reagent alone or as part of a biotin labeling kit. The labeling kits are designed and supplied with all the necessary reagents, equipment and instructions necessary for optimal reaction conditions, efficient labeling, removal of unbound biotin, and quantification of biotin labeling, for the conjugation of biotin to carbohydrates.

Each kit is supplied with 25 milligrams of the specific HOOK™ Carbohydrate Reactive Biotin Reagent, a specific Optimizer Buffer™ for enhanced conjugation, Spin-OUT™ columns for rapid (less than 10 minute) purification of labeled protein, and reagents to determine the amount of biotinylation. The kits are each designed for the coupling of 1 to 10 milligrams protein in 1 milliliter buffer, suitable for 10 couplings.

Several factors must be considered when coupling a biotin reagent to a protein to ensure a successful reaction. The primary consideration is the selection of the biotinylation reagent itself. G-Biosciences offers a wide range of biotin reagents with variations in their reactive groups, spacer arm lengths, solubility, membrane permeability and reversibility. All of these factors must be considered and are dependent on your protein/peptide.