Clawing back: broadening the notion of metal chelators in medicine

► Not all chelators are the same: more than metal sequestration and elimination. ► Metal chelates can redistribute metals across biological membranes. ► Metal-chelating fragments provide leads for metalloenzyme inhibition. ► Metal chelation can enhance metal reactivity and thus cytotoxicity. ► Prochelators provide site-activated metal chelation and passivation.