EZ-Link™ Sulfo-NHS-Biotinylation Kit

Catalog number: 21425

Thermo Scientific™  Related applications: Protein Labeling & Crosslinking

Error loading your content!

  Catalog number
Select a plan
Unit size
Price ({{currency}}) Your price ({{currency}}) Availability Qty
{{product.sku}} {{product.sku}}
also known as {{product.formattedSku}} 
{{subscriptionDetails.selectedRatePlan.billingPeriod}} {{subscriptionDetails.selectedRatePlan.billingPeriod}} {{product.availability.message}}
Pro add-ons

Your on-site stock

›› {{supplyCenter.scName}}({{scProduct.stockOnHand}} In stock)
›› {{supplyCenter.scName}}(Out of stock)
›› {{supplyCenter.scName}}
This item is not currently available on-site. Depending on your Supply Center settings you may be able to add the item to cart above else use the Order Non-Stocked Items' tab on the Supply Center home page.
Back to top


The Thermo Scientific EZ-Link Sulfo-NHS-Biotinylation Kit contains reagents sufficient for 10 biotinylation reactions (e.g., 1–10 mg antibody per reaction). The EZ-Link Sulfo-NHS-Biotin reagent included in the kit is a short-chain, water-soluble biotinylation reagent used for labeling antibodies, proteins and other molecules that have primary amines.

Features of EZ-Link Sulfo-NHS-Biotin:

Protein labeling—biotinylate antibodies to facilitate immobilization, purification or detection using streptavidin resins or probes
Cell surface labeling—biotinylates only surface proteins of whole cells because the negatively charged reagent does not permeate cell membranes
Amine-reactive—reacts with primary amines (-NH2), such as lysine side-chains or the amino-termini of polypeptides
Soluble—charged sulfo-NHS group increases reagent water solubility compared to ordinary NHS-ester compounds
Irreversible—forms permanent amide bonds; spacer arm cannot be cleaved
Very short—spacer arm (total length added to target) is 13.5 angstroms; it consists of the native biotin valeric acid group only.

Sulfo-NHS-Biotin is the shortest of three very similar EZ-Link Reagents that are water-soluble, non-cleavable, and enable simple and efficient biotinylation of antibodies, proteins and any other primary amine-containing macromolecules in solution. Specific labeling of cell surface proteins is another common application for these uniquely water-soluble and membrane impermeable reagents. Differing only in their spacer arm lengths, the three Sulfo-NHS-ester reagents offer the possibility of optimizing labeling and detection experiments where steric hindrance of biotin binding is an important factor. Sulfo-NHS-Biotin is offered in several package sizes and as complete protein labeling kits.

We manufacture biotin reagents to ensure the highest possible overall product integrity, consistency and performance for the intended research applications.

N-Hydroxysulfosuccinimide (NHS) esters of biotin are the most popular type of biotinylation reagent. NHS-activated biotins react efficiently with primary amino groups (-NH2) in alkaline buffers to form stable amide bonds. Proteins (e.g., antibodies) typically have several primary amines that are available as targets for labeling, including the side chain of lysine (K) residues and the N-terminus of each polypeptide.

Varieties of biotin NHS-ester reagents differ in length, solubility, cell permeability and cleavability. Non-sulfonated NHS-biotins are cell permeable but must be dissolved in organic solvent such as DMSO or DMF. Sulfo-NHS biotins (and those with pegylated spacers) are directly water soluble but not membrane permeable. Varieties containing disulfide bonds can be cleaved using reducing agents, enabling the biotin group to be disconnected from the labeled protein.

Related Products
EZ-Link™ Sulfo-NHS-Biotin
EZ-Link™ Micro Sulfo-NHS-Biotinylation Kit
For Research Use Only. Not for use in diagnostic procedures.


Label or Dye: Biotin
Product Size: 10 reactions
Labeling Scale: 1-10 mg
Labeling Target: Proteins (General), Antibodies (General)

Contents & storage

Sufficient For: 10 labeling reactions, each with 1 to 10 mg of antibody
• EZ-Link Sulfo-NHS-Biotin, 25 mg
• PBS Pack (makes 500mL), 1 pack
• Zeba Spin Desalting Columns (7K MWCO), 5 mL, 10 columns
• HABA Solution, 1 mL
• Avidin, 10 mg

Store avidin and vial of biotin reagent (with desiccant) at -20°C. Store remaining kit components at 4°C.


Manuals & protocols

Recommended products