These supramolecular cages are dynamic in their structural attributes since intermolecular hydrogen bonds can act as dynamic gates for the controlled passage of ions as well as small nanoparticles into and out of the cages. By virtue of the high density of hydroxyl groups, the interior of these cages is polar and hydrophilic, making it possible to transport and reduce metal ions in the cages. Also, the hydroxyl groups help to passivate the surfaces of the silver metal nanoparticles.