3D image of part of cells with a biotin labeled molecule

Biotin and desthiobiotin labeling reagents are used for biotinylation of proteins, peptides, antibodies, and other biomolecules. These reagents target specific functional groups or residues on biomolecules, including primary amines and sulfhydryls. Biotin labeling reagents are offered as single-package reagents or convenient kits, as no-weigh packaging formats for quick and convenient working solutions, and as premium grade reagents with high-quality formulations.

Use the Biotinylation Reagent Selection Tool to aid in identifying the optimal labeling reagent for your application. Additionally, the Bioconjugation Technical Handbook can be used to support your biotin labeling experiments. Explore our Biotin Quantitation Reagents and HABA Calculator Tool to measure the amount of biotin attached to your biomolecule of interest.

What is biotinylation?

Biotinylation is the labeling of biotin to a molecule of interest such as a protein, antibody, peptide, or other biomolecule (Figure 1). Biotinylated proteins typically retain biological activity because the biotin group is relatively small. Biotin (Figure 2) is a naturally occurring vitamin that binds to avidin and streptavidin proteins with high affinity. The bond formation between biotin and avidin is rapid and, once formed, is unaffected by most extremes of pH, organic solvents, and other denaturing agents. Learn more about avidin-biotin interaction.

Biotin labeling reagents target specific functional groups or residues on biomolecules such as primary amines, sulfhydryls, carboxyls, or carbohydrates. Biotinylated proteins can be captured or detected by enzyme-linked immunosorbent assay (ELISA), western blot, immunohistochemistry (IHC), immunoprecipitation (IP), or flow cytometry applications. Learn more about biotinylation.

Choose the right biotin labeling reagent for your application using our Biotinylation Reagent Selection Tool, or select from our biotinylation reagent guide, our Biotin no-weigh packaging, or our Biotin premium grade reagents options below.

Protein with a primary amine group biotinylated for detection

Figure 1. Biotinylated protein. If drawn to scale, the oval representing the protein would be many times larger than the structures and would likely contain several amino groups. Note that NHS is a leaving group (byproduct) in the reaction. The leaving group and any non-reacted biotin reagent are removed during the desalting step.
 

Chemical structure of biotin composed of a ureido ring joined with a tetrahydrothiophene ring
Figure 2. Biotin structure. Biotin, also known as B-vitamin B7 (formerly vitamin H and coenzyme R) is water soluble. The molecule is comprised of a ureido ring joined with a tetrahydrothiophene ring. A coenzyme for carboxylase enzymes, biotin is required for the synthesis of fatty acids, isoleucine and valine. Biotin is also involved in gluconeogenesis.

Biotinylation reagents based on reactive chemistry

*1-10 mg biotinylation kits include reagents for a HABA assay for measuring the level of biotin incorporation

Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link BMCC-Biotin32.6NoNoYes
EZ-Link HPDP-Biotin 29.2YesNoYes
EZ-Link Iodoacetyl-LC-Biotin27.1NoNoYes
EZ-Link Iodoacetyl-PEG2-Biotin24.7NoYesNo
EZ-Link Maleimide PEG11-Biotin59.1NoYesNo
Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Amine-PEG2-Biotin20.4NoYesNo
EZ-Link Amine-PEG3-Biotin22.9NoYesNo
EZ-Link Amine-PEG11-Biotin53.2NoYesNo
EZ-Link Biocytin20.1NoYesNo
EZ-Link Pentylamine-Biotin18.9NoYes  No 
Oder productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Alkoxyamine-PEG12-Biotin55.4NoYesNo
EZ-Link Alkoxyamine-PEG4-Biotin27NoYes  No 
EZ-Link Hydrazide-Biotin15.7NoYesYes 
EZ-Link Biotin-LC-Hydrazide24.7NoNoYes
EZ-Link Hydrazide-PEG4-Biotin31.3NoYesNo
Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Psoralen-PEG3-Biotin39.6 No  Yes  No
EZ-Link TFPA-PEG3-Biotin33.4NoNo Yes
Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Biotin-PEG12-DBCODBCO (alkyne)NoNoEZ-Link Biotin-PEG12-DBCO
Biotin AzideAzideNoNoBiotin Azide
Biotin AlkyneAlkyneNoNoBiotin Alkyne

*1-10 mg biotinylation kits include reagents for a HABA assay for measuring the level of biotin incorporation

Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link BMCC-Biotin32.6NoNoYes
EZ-Link HPDP-Biotin 29.2YesNoYes
EZ-Link Iodoacetyl-LC-Biotin27.1NoNoYes
EZ-Link Iodoacetyl-PEG2-Biotin24.7NoYesNo
EZ-Link Maleimide PEG11-Biotin59.1NoYesNo
Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Amine-PEG2-Biotin20.4NoYesNo
EZ-Link Amine-PEG3-Biotin22.9NoYesNo
EZ-Link Amine-PEG11-Biotin53.2NoYesNo
EZ-Link Biocytin20.1NoYesNo
EZ-Link Pentylamine-Biotin18.9NoYes  No 
Oder productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Alkoxyamine-PEG12-Biotin55.4NoYesNo
EZ-Link Alkoxyamine-PEG4-Biotin27NoYes  No 
EZ-Link Hydrazide-Biotin15.7NoYesYes 
EZ-Link Biotin-LC-Hydrazide24.7NoNoYes
EZ-Link Hydrazide-PEG4-Biotin31.3NoYesNo
Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Psoralen-PEG3-Biotin39.6 No  Yes  No
EZ-Link TFPA-PEG3-Biotin33.4NoNo Yes
Order productsSpacer Arm (Å)Cleavable?Water-soluble?Membrane permeable?
EZ-Link Biotin-PEG12-DBCODBCO (alkyne)NoNoEZ-Link Biotin-PEG12-DBCO
Biotin AzideAzideNoNoBiotin Azide
Biotin AlkyneAlkyneNoNoBiotin Alkyne

Biotin no-weigh packaging

Biotin no-weigh packaging formats offer quick and convenient ready-to-use solutions. This format eliminates the need to weigh out small amounts of dry compounds and eliminates the waste of unused material. Simply reconstitute and the reagent is ready to use at the desired concentration.

Biotin premium grade reagents

Biotin premium grade reagents are high-quality reagents formulated for applications where product integrity and risk minimalization are essential. These premium grade reagents are ideal for long-term research projects that require consistent performance. Biotin premium grade products provide quality assurance review, lot sample retention, change control notification, along with an extra level of analytical testing and chemical characterization.

Comparison of specifications between premium and standard grade reagents

Test parameterTest methodPremium gradeStandard grade
PurityQuantitative NMR using an internal standardYesYes
VisualColor assessmentYesYes
SolubilitySample dissolves at specified concentration in deionized water to yield a clear, colorless solutionYesYes
IdentityInfrared spectroscopyYesYes
Mass identityMass spectrometryYesNA
Water contentKarl Fischer titrationYesNA
Trace metalsInductively coupled plasma mass spectrometry (ICP-MS)YesNA
Elemental analysisCombustion analysis (values reported for C, H, N, O, and S)YesNA
Residual solvent analysisHeadspace gas chromatographyUpon requestNA

Desthiobiotin vs. biotin

Desthiobiotin is a modified form of biotin that binds less tightly to avidin and streptavidin than biotin while still providing excellent specificity in affinity purification methods (Figure 3). Unlike biomolecules that are labeled with biotin, proteins and other targets that are labeled with desthiobiotin can be eluted without harsh, denaturing conditions. As a result, desthiobioinylation is an alternative to biotinylation for applications requiring gentle elution and recovery of the labeled target.

Structure of biotin compared to desthiobiotin
Figure 3. Comparison of the chemical structures of biotin and desthiobiotin.

Assays and kits that use desthiobiotin

ProductDesthiobiotin reagentApplication
Desthiobiotinylation and Pull-Down KitSulfo-NHS-LC-DesthiobiotinLabel a purified protein and use it to affinity purify interaction complexes in which it participates
RNA 3' End Desthiobiotinylation KitDesthiobiotinylated Cytidine BisphosphateEnzymatically label an RNA oligo for use in Magnetic RNA-Protein Pull-Down Kit
Active Serine Hydrolase ProbesDesthiobiotin-fluorophosphonateCovalently label the active site of serine hydrolases to enable their selective enrichment
Kinase Enrichment KitsDesthiobiotin-ATP; Desthiobiotin-ADPCovalently label the active site of ATPases, including chaperones and metabolic enzymes, to enable their selective enrichment

For Research Use Only. Not for use in diagnostic procedures.