The present disclosure is directed to meditope-antibody covalent binding modalities that can be activated only after the meditope associates with a binding site on the meditope-enabled antibody. To this end, provided herein is a meditope engineered to contain a photoreactive functional group at one or more specific location(s) on the meditope so as not interfere with the specific noncovalent molecular interaction with the binding site on the meditope-enabled antibody, but still permits, and enhances, covalent bond formation. This methodology, with its speed, accuracy, consistency and simplicity has evident advantages for the development of antibody-drug conjugates.
