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Thiol-Reactive Dyes

Maleimide reacts with thiol groups to form thioether-coupled products. The reaction can take place at pH 7 in the presence of amines. At neutral pH, the maleimide group does not react with histidine or arginine. Maleimide labeling can be a useful alternative to succinimidyl ester labeling in cases where modification of lysines alters antibody binding affinity or other biological activity of the target protein. We offer more than 20 bright and photostable CF® Dye Maleimides.

Methanethiosulfonate (MTS) is a fast-reacting and highly selective thiol-reactive functional group. We offer CF® Dye MTS with a selection of popular colors. We also offer MTS thiol-modifying and cross-linking agents.

We also offer many classic thiol-reactive dyes and biotin, as well as reducing agents commonly used in thiol conjugation protocols.