Now, what's so special about these spherical gel beads? Well, these gel beads consist of a hydrated polymer, such as, for example, dexterin, which is a carbohydrate. And even though this molecule, this bead, is insoluble, it doesn't dissolve in aqueous solutions. It contains these tiny holes, these tiny pores, and that allows small molecules to pass through those tiny pores. So this is our setup. We have the funnel inside.