Thermo Scientific EZ-Link Sulfo-NHS-SS-Biotin is a water-soluble NHS-ester biotin labeling reagent. The spacer arm contains a cleavable disulfide bond and is suitable for reversible labeling of proteins and cell surface primary amines.

Features of EZ-Link Sulfo-NHS-SS-Biotin:

• Solid-phase analysis of biotin-labeled antibodies via streptavidin resin or probes ionization, affinity purification or detection
• Cell surface labeling—Biotin labeling reagents are negatively charged and do not penetrate cell membranes, so they can only target surface proteins of intact cells. Prime label
• Amino reactivity—reacts with primary amines (-NH2), such as lysine side chains or the amino terminus of peptides
• Cleaved —The disulfide bond in the spacer arm makes it possible to remove the biotin label by a reducing agent such as DTT, leaving only a small sulfhydryl group on the labeled molecule.
• Solubility – The charged sulfo-NHS group enhances the water solubility of the reagent compared to ordinary NHS-ester compounds
• Medium length— The spacer arm (total length added to the target) is 24.3 Angstroms; it consists of natural biotin valerate groups with a 7-atom chain.

Sulfo-NHS-SS-Biotin is a thiol-cleavable amino-reactive biotin labeling reagent that contains an extended spacer arm to reduce the steric hindrance of streptavidin connection. This reagent has good water solubility and can achieve biotin labeling without organic solvents such as DMSO or DMF. Therefore, it is suitable for those situations where the relevant solvents cannot be tolerated or the solvent complicates the conditions. The sulfonated group of this compound can prevent it from penetrating the cell membrane, and the cleavable spacer arm can also help the initially biotin-labeled protein to be released from the streptavidin affinity column, so it is particularly suitable for labeling and purification. Cell surface proteins.

In addition, we also provide high-quality biotin reagents to meet the integrity, consistency and performance requirements of research applications.

N- N-hydroxysuccinimide (NHS) ester is the most common biotin labeling reagent . NHS-activated biotin reacts with primary amine groups (-NH2) in alkaline buffers to form stable amide bonds. Proteins (such as antibodies) usually have many primary amine groups and therefore can be used as targets for (biotin) labeling, including the side chain of lysine (K) and the amino terminus of each polypeptide chain (all containing primary amine groups) .

Different biotin NHS ester reagents have different spacer arm lengths, solubility, cell permeability and cleavability: non-sulfonated NHS biotin is permeable Cell membrane, but must be dissolved in organic solvents such as DMSO or DMF; Sulfo-NHS biotin (and products with PEGylated spacer arms) are water-soluble but not cell membrane permeable; containing disulfide bonds The reagent can be cleaved by a reducing agent to remove the biotin group from the labeled protein.

Related resources:
Biotinylation Reagent Selection Guide
A review of biotin labeling methods and applications< br>Cross-linking chemical methods (and labeling reagents)

Related products:
Pierce Cell Surface Protein Isolation Kit
NHS-PEG4-Biotin and Kit — 29.0 Angstrom PEGylated Spacer
Sulfo-NHS-LC-Biotin and Kit — 22.4 Angstrom spacer, non-cleavable
All biotin labeling reagents
Avidin , streptavidin, NeutrAvidin affinity resin