The deep, murky pigment known as Prussian blue put the "blue" in traditional blueprints, colored Hokusai's "Great Wave off Kanagawa" and today is used for industrial purposes, from laundry to battery components to poison control. Now, research from the University of Chicago Pritzker School of Molecular Engineering (UChicago PME) has found new uses for the important and inexpensive chemical and new understanding of the mechanisms that make Prussian blue analogs (PBAs) unique.