Thermo Scientific EZ-Link Hydrazide-PEG4-Biotin (also called Biotin-PEG4-Hydrazide) is an aldehyde-reactive biotinylation reagent that contains a 4-unit polyethylene glycol (PEG) spacer arm for increased hydrophilicity.
Biotin-PEG4-Hydrazide enables biotinylation of glycoproteins and other molecules containing aldehydes or oxidizable sugar groups. The hydrazide group reacts spontaneously with aldehyde or ketone groups to form a stable hydrazone bond. Aldehyde groups can be created by gentle periodate oxidation of cis-diols in sialic acid and other sugars in carbohydrates. The hydrophilic, 4-unit polyethylene glycol (PEG) spacer arm imparts water solubility that is transferred to the biotinylated molecule, thus reducing aggregation of labeled proteins stored in solution. The PEG segment also adds length and flexibility to the spacer arm, minimizing steric hindrance involved with binding to avidin molecules.
- Glycoprotein labeling – biotinylate glycosylated proteins at sialic acid residues for detection or purification using streptavidin probes or resins
- Cell surface labeling – biotinylate and isolate cell surface glycoproteins; reagent does not permeate membranes of whole cells
- Aldehyde-reactive – reacts with aldehydes formed by periodate-oxidation of sugar groups
- Hydrazide-activated – perform reactions at pH 4 to 6 in buffers such as sodium acetate
- Pegylated – spacer arm contains a hydrophilic, 4-unit, polyethylene glycol (PEG) group
- Enhances solubility – pegylation imparts water solubility to the biotinylated molecule, helping to prevent aggregation of biotinylated antibodies stored in solution
- Irreversible – forms semi-permanent hydrazone bonds; spacer arm cannot be cleaved
- Solubility – usually dissolved in DMSO to make concentrated stock solution
- Long reach – spacer arm (total length added to target) is 31.3 angstroms
|Chemical structure of Hydrazide-PEG4-Biotin. This biotinylation reagent labels glycoproteins and other molecules having carbohydrates that can be oxidized with periodate to expose aldehydes. For more information, see our review of Hydrazide Reaction Chemistry.
Properties of Hydrazide-PEG4-Biotin. This aldehyde-reactive biotinylation reagent has an intermediate-length spacer arm, which contains hydrophilic ethylene glycol groups.
|Spacer arm length
|Mass added to target
||Dissolve in DMSO to make 250mM stock
||4°C; -20°C as stock solution
||Hydrazide, reacts with aldehydes at pH 4 to 6
We manufacture biotin reagents to ensure the highest possible overall product integrity, consistency and performance for the intended research applications.
Biotinylation reagents differ in reactivity, length, solubility, cell permeability and cleavability. Hydrazides and alkoxyamines are two types of carbonyl-reactive groups. Hydrazides (–NH-NH2) react specifically with aldehyde groups in slightly acidic conditions to form hydrazone linkages; these can be further reduced to stable secondary amine bonds using sodium cyanoborohydride (Part No. 44892). The reaction is more efficient in the presence of aniline (Part No. 88944). Alternatively, hydrazides can be conjugated to carboxylic acids using EDC carbodiimide chemistry.
Reactive aldehyde groups can be generated in glycoproteins and other polysaccharide compounds by oxidation of constituent sugar diols using sodium periodiate (Part No. 20504). Sialic acid residues are common components of protein glycosylation and are easily converted to aldehydes with 1mM NaIO4.
- Edwards, S.W., et al. (1999). J. Biol. Chem. 274, 16331-16336.
- Hermanson, G.T. (1996). Bioconjugate Techniques, Academic Press (Product # 20002).
- Scott, M.G., et al. (2000). J. Immunol. 164(2), 549-553.
Biotinylation Reagents Selection Guide
Review of Biotinylation Methods and Applications
Review of Glycosylation and Glycoprotein Methods
Chemistry of Crosslinking (and Labeling Reagents)
Non-PEG Biotin-Hydrazide Reagents
Sodium meta-Periodate – carbohydrate oxidation reagent
All Biotinylation Reagents
Avidin, Streptavidin, NeutrAvidin Affinity Resins