4-(N-Maleimidomethyl)cyclohexanecarboxylic acid N-hydroxysuccinimide ester (SMCC) is a heterobifunctional cross-linking reagent containing amine and sulfhydryl reactivity. It is typically coupled initially to molecules containing primary amine by amide bond buffered at pH 7.5 (6.5-8.5). The second coupling is specific for molecules containing free sulfhydryl by thioether linkage buffered at pH 6.8 (6.5-7.0). SMCC contains nine atom linker. An extended aliphatic spacer stabilizes the maleimide prior to coupling compared to aromatic spacers.
4-(N-Maleimidomethyl)cyclohexanecarboxylic acid N-hydroxysuccinimide ester (SMCC) is useful for the preparation of enzyme immunoconjugates and hapten carrier molecule conjugates.