Biotinylation is a widely used technique in biochemistry that involves the covalent attachment of biotin to a molecule of interest. Biotin is a small molecule that can bind very tightly to the protein avidin or streptavidin, allowing researchers to use biotinylated molecules as probes for various applications such as protein purification, detection, and visualization.
There are several reagents that can be used to biotinylate a molecule, including:
NHS-biotin: This reagent is a popular choice for biotinylating primary amines in proteins and other biomolecules. NHS-biotin reacts with primary amines to form a stable amide bond.
Sulfo-NHS-biotin: This is a water-soluble version of NHS-biotin that can be used to biotinylate proteins in aqueous solutions. Sulfo-NHS-biotin is often used for labeling antibodies and other proteins.
Maleimide-biotin: This reagent is used to biotinylate sulfhydryl groups in proteins. Maleimide-biotin reacts specifically with sulfhydryl groups to form a stable thioether bond.
EZ-Link™ Biotin-PEO Avail™ Long Chain NHS-ester: This is a biotinylating reagent that can be used to attach biotin to proteins, peptides, and other molecules with primary amines. The long PEG spacer arm in the reagent can help to reduce steric hindrance and improve accessibility of the biotin tag.
Desthiobiotin: This molecule is similar to biotin, but lacks the sulfur atom that forms the strongest bond with avidin and streptavidin. Desthiobiotin can be used as a reversible biotinylating agent, allowing researchers to remove the biotin tag if necessary.
These are just a few examples of the many biotinylation reagents available. The choice of reagent will depend on the specific application and the properties of the molecule being labeled.