Thermo Scientific Pierce SMCC has N-hydroxysuccinimide (NHS) ester and maleimide groups Heterobifunctional cross-linking agent, capable of covalent coupling of amine- and sulfhydryl-containing molecules. NHS esters react with primary amines at pH 7–9 to form amide bonds, whereas maleimides react with sulfhydryl groups at pH 6.5–7.5 to form stable thioether bonds. In aqueous solutions, NHS ester hydrolytic degradation is a competing reaction, and its rate increases with increasing pH. Maleimide groups are more stable than NHS-ester groups, but hydrolyze slowly and lose reaction specificity toward sulfhydryl groups at pH values > 7.5. For these reasons, coupling with these cross-linkers is usually performed at pH 7.2–7.5, with reaction with NHS ester (amine targeting) either before or simultaneously with maleimide (thiol targeting) conduct.

The cyclohexane ring in the spacer arm of this reagent reduces the rate of hydrolysis of the maleimide group compared to similar reagents without this ring. This feature allows proteins containing SMCC-activated maleimide to be lyophilized and stored for subsequent conjugation with sulfhydryl-containing molecules. Many maleimide-activated protein products are produced in this manner.

Thermo Scientific No-Weigh products are specialty reagents available in pre-portioned formats. Pre-weighed packaging eliminates repeated opening and closing of vials, preventing loss of reagent reactivity and contamination over time. With this format, a fresh vial of reagent can be used at a time, eliminating the hassle of weighing small amounts of reagent and reducing concerns about reagent stability.

Features of SMCC:

•Reactive groups:NHS Ester&Maleimide
• Reacts with:Amino and thiol groups
• Not cleavable< br>• Water insoluble (dissolve first in DMF or DMSO); compare to Sulfo-SMCC
• High-purity maleimide-activated derivatives can be generated using high-purity crystalline reagents
• The cyclohexane bridge provides additional stability to the maleimide group, making SMCC maleimide-activated Ideal cross-linker for proteins. The maleimide group is stable in 0.1 M sodium phosphate buffer (pH 7) for 64 hours at 4°C.

Sulfosuccinimide-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (Sulfo-SMCC) is a Non-cleavable but membrane-permeable cross-linker. It contains an amine-reactiveN-hydroxysuccinimide (NHS ester) and thiol-reactive maleimide groups. NHS esters react with primary amines at pH 7-9 to form stable amide bonds. Maleimide reacts with sulfhydryl groups at pH 6.5-7.5 to form stable thioether bonds. The maleimide group of SMCC and Sulfo-SMCC due to the presence of a cyclohexane bridge in the spacer arm The pellet is stable at pH values up to 7.5.

Applications:
•Abzyme labeling - both enzyme and antibody specificity are preserved
•Create specific bioconjugation through one- or two-step cross-linking reactions< br>•Creation of sulfhydryl-reactive, maleimide-activated carrier proteins for conjugation of haptens

Specifications:
We produce SMCC with higher specifications , resulting in extremely specific bioconjugated and maleimide-activated proteins that ensure data integrity and provide an extremely high degree of cross-linking consistency. Every lot of SMCC is tested and meets the following lower specifications.

• Identification: IR scan shows only the structure and peak characteristics of the functional groups of the SMCC cross-linker
• Purity: ≥ 92% (by NMR)

Product References:
Crosslinking Agent Application Guide—Search for recent references on this product