Thermo Scientific Pierce BS³ (Sulfo-DSS) is bis(sulfosuccinimidyl)suberate, an amine-to-amine crosslinker that is homobifunctional, water-soluble, non-cleavable and membrane impermeable.

BS³ contains an amine-reactive N-hydroxysulfosuccinimide (NHS) ester at each end of an 8-carbon spacer arm. NHS esters react with primary amines at pH 7-9 to form stable amide bonds, along with release of the N-hydroxysulfosuccinimide leaving group. Proteins, including antibodies, generally have several primary amines in the side chain of lysine (K) residues and the N-terminus of each polypeptide that are available as targets for NHS-ester crosslinking reagents.

No-Weigh microtube handling:
Each of the eight microtubes contains 2 mg of crosslinker. Puncture foil with a pipette tip and add DMSO or DMF to the DSS or aqueous buffer to the BS³. Store the microtube strip in the foil pouch provided. Used microtubes may be cut from the unused microtubes and discarded.

Features of BS³:

• Reactive groups: sulfo-NHS ester (both ends)
• Reactive towards: amino groups (primary amines)
• Amine-reactive Sulfo-NHS ester reacts rapidly with any primary amine-containing molecule
• Water-soluble; compare with DSS
• Membrane-impermeable, allowing for cell surface labeling
• High-purity, crystalline reagent can be used to create high-purity crosslinked conjugates

Because it contains the hydrophilic sulfonyl moiety, BS³ crosslinker is soluble up to ∼100 mM in water and many commonly used buffers, thus avoiding the use of organic solvents which may perturb protein structure. DSS, the non-water soluble analog of BS³ is also available for applications that require a less hydrophilic crosslinker (e.g., to effect intracellular crosslinking). DSS and BS³ have essentially identical crosslinking activity toward primary amines.

Properties of BS³:
• Alternative names: Sulfo-DSS
• Molecular formula: C₁₆H₁₈N₂O₁₄S₂Na₂
• Molecular weight: 572.43
• Spacer arm length: 11.4 Å (8 atoms)
• CAS number: 82436-77-9
• Reactive groups: NHS esters, react with primary amines at pH 7.0-9.0

Applications:
• Crosslink cell-surface proteins prior to cell lysis and immunoprecipitation
• Identify receptor-ligand interactions by chemical crosslinking
• 'Fix' protein interactions to allow identification of weak or transient protein interactions
• Identify near-neighbor protein interactions
• Protein crosslinking to create bioconjugates via single-step reactions
• Immobilize proteins onto amine-coated surfaces

BS³ Specifications:
We manufacture BS³ to the highest specifications to produce the most specific bioconjugates, ensure the integrity of your data and to provide you with the highest degree of consistency. Each lot of BS³ is tested to meet the following minimum specifications:
• Purity: > 93% by quantitative NMR (the highest standard for crosslinker purity)
• Solubility: > 5.8 mg/mL in DI water, clear solution with no insoluble material

Product References
Crosslinker Application Guide -- search for recent literature references for this product

Related Products
Pierce™ Premium Grade BS3
DSS (disuccinimidyl suberate)
BS(PEG)5 (PEGylated bis(sulfosuccinimidyl)suberate)
BS(PEG)9 (PEGylated bis(sulfosuccinimidyl)suberate)