Labelling

FAM-amido hexamethylene carbamate-PAB-Cit-Val-Alkyne is a cleavable ADC linker with fluorescein that undergoes enzymatic transamination. The alkyne group can react with azides via copper catalyzed Click Chemistry reactions. The Val-Cit linker was designed to be cleaved by cathepsin B. Since this enzyme is only present in the lysosome, the ADC payload will be released only in the cell.