Bis-PEG2-PFP ester is also a non-cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1]. Bis-PEG2-PFP ester is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[2].
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[2].
[1]. Matthew David DOROSKI, et al. Cytotoxic peptides and antibody drug conjugates thereof. WO2013072813A2.
[2]. An S, et al. Small-molecule PROTACs: An emerging and promising approach for the development of targeted therapy drugs. EBioMedicine. 2018 Oct;36:553-562.