Amino-Tri-(carboxyethoxymethyl)-methane hydrochloride is a cleavable PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Amino-Tri-(carboxyethoxymethyl)-methan hydrochloride is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs. In Vitro ADCs are comprised of an antibody to which is attached an ADC cytotoxin through an ADC linker. 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. MCE has not independently confirmed the accuracy of these methods. They are for reference only.