Description
Sulfo EMCS ([N-(E-maleimidocaproyloxy)-sulfo succinimide ester), a water-soluble analog of EMCS is a heterobifunctional cross-linker, containing N-hydroxysuccinimide (NHS) ester and maleimide groups that allow covalent conjugation of amine- and sulfhydryl- containing molecules. NHS esters react with primary amines at pH 7-9 to form amide bonds, while maleimides react with sulfhydryl groups at pH 6.5-7.5 to form stable thioether bonds. In aqueous solutions, hydrolytic degradation of the NHS ester is a competing reaction whose rate increases with pH. The maleimide group is more stable than the NHS-ester group but will slowly hydrolyze and also lose its reaction specificity for sulfhydryls at pH values > 7.5. For these reasons, conjugation experiments involving these cross-linkers are usually performed at a pH range of 7.2-7.5, with the NHS-ester (amine-targeted) reaction being accomplished before or simultaneously with the maleimide (sulfhydryl-targeted) reaction.
Features and Benefits
- Reactive groups: sulfo-NHS ester and maleimide
- Reactive towards: amino and sulfhydryl groups
- Sulfo-NHS ester end couples with primary amines at pH 7-9 to form stable amide bonds
- Maleimide reacts with -SH groups at pH 6.5-7.5, forming stable thioether linkages
- Non-cleavable
- Water-soluble (compare to EMCS)
- Aliphatic spacer offers low potential for eliciting an immune response
Additional information
Size | 50 mg, 100 mg |
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