Azido-PEG3-Val-Cit-PAB-PNP is a cleavable peptide ADC linker. The Val-Cit will specifically be cleaved by Cathepsin B. PNP groupg is a good leaving group when treating with aminebearing payload. Azido group will react with DBCO, BCN or other Alkyne group through click chemistry, PEG spacer increases aqueous solubility.
