Azido-PEG8-acid is a non-cleavable 8 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Azido-PEG8-acid is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1].
ADCs are comprised of an antibody to which is attached an ADC cytotoxin through an ADC linker[1].PROTACs contain two different ligands connected by a linker; one is a ligand for an E3 ubiquitin ligase and the other is for the target protein. PROTACs exploit the intracellular ubiquitin-proteasome system to selectively degrade target proteins[1].
[1]. Tan M, et al. Peptide-targeted Nanoglobular Gd-DOTA monoamide conjugates for magnetic resonance cancer molecular imaging. Biomacromolecules. 2010 Mar 8;11(3):754-61.