Protein Hydrogel Microbeads for Selective Uranium Mining from Seawater.

Practical methods for oceanic uranium extraction have yet to be developed in order to tap into the vast uranium reserve in the ocean as an alternative energy. Here we present a protein hydrogel system containing a network of recently engineered super uranyl binding proteins (SUPs) that is assembled through thiol-maleimide click chemistry under mild conditions. Monodisperse SUP hydrogel microbeads fabricated by a microfluidic device further enable uranyl (UO22+) enrichment from natural seawater with great efficiency (enrichment index, K = 2.5 × 103) and selectivity. Our results demonstrate the feasibility of using protein hydrogels to extract uranium from the ocean.