TCO-PEG4-maleimide is a bifunctional crosslinker containing a TCO moiety and a maleimide group. The maleimide group can react with thiol groups to form a stable thioester bond between pH 6.5 to 7.5. The hydrophilic PEG spacer increases the water solubility of a compound in aqueous media. TCO can be used to label antibodies, proteins and othe rtetrazine-containing macromolecules.
