Propargyl-PEG2-acid is a non-cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Propargyl-PEG2-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]. Sano K, et al. Short PEG-linkers improve the performance of targeted, activatable monoclonal antibody-indocyanine green optical imaging probes. Bioconjug Chem. 2013 May 15;24(5):811-6.