TCO-PEG3-NHS Ester is a PEG linker containing a TCO moiety and a NHS ester. The hydrophilic PEG spacer increases water-solubility and a decreases steric hindrance during ligation. This reagent can be used to label antibodies, proteins and other primary amine-containing macromolecules with TCO moiety. Reagent grade, for research purpose. Please contact us for GMP-grade inquiries.