(R, E) -TCO-PEG8-acid

This ADC linker, featuring an 8-unit PEG spacer and a trans-cyclooctene (TCO) group, enables rapid bioorthogonal conjugation via iEDDA with tetrazine probes. It is widely used for constructing antibody-drug conjugates (ADCs) and targeted delivery systems in both in vitro and in vivo research applications.