Abstract
Over millennia, nature has evolved an ability to selectively recognize and sequester specific metal ions by employing a wide variety of supramolecular chelators. Iron-specific molecular carriers—siderophores—are noteworthy for their structural elegance, while exhibiting some of the strongest and most selective binding towards a specific metal ion. Development of simple uranyl (UO 2 2+ ) recognition motifs possessing siderophore-like selectivity, however, presents a challenge. Herein we report a comprehensive theoretical, crystallographic and spectroscopic studies on the UO 2 2+ binding with a non-toxic siderophore-inspired chelator, 2,6-bis[hydroxy(methyl)amino]-4-morpholino-1,3,5-triazine (H 2 BHT). The optimal pK a values and structural preorganization endow H 2 BHT with one of the highest uranyl binding affinity and selectivity among molecular chelators. The results of small-molecule standards are validated by a proof-of-principle development of the H 2 BHT-functionalized polymeric adsorbent material that affords high uranium uptake capacity even in the presence of competing vanadium (V) ions in aqueous medium.
Original language | English |
---|---|
Article number | 819 |
Journal | Nature Communications |
Volume | 10 |
Issue number | 1 |
DOIs | |
State | Published - Dec 1 2019 |
Funding
This work was sponsored by the U.S. Department of Energy, Office of Nuclear Energy, under Contract DE-AC05-00OR22725 with Oak Ridge National Laboratory, managed by UT-Battelle, LLC, and Contract DE-AC02-05CH11231 with Lawrence Berkeley National Laboratory. The computational work (A.S.I. and V.S.B.) used resources of the National Energy Research Scientific Computing Center and the Compute and Data Environment for Science (CADES) at the Oak Ridge National Laboratory, both of which are supported by the Office of Science of the U.S. Department of Energy under contracts DE-AC02-05CH11231 and DE-AC05-00OR22725, respectively. The synthesis and characterization of the polymeric adsorbent (S.J.-P., I.P., S.D., and R.T.M.), thermodynamic and spectroscopic experimental work on small-molecule standard (B.F.P., Z.Z., J.A., and L.R.) and all computational studies (A.S.I. and V.S.B.) were supported by the Fuel Cycle Research and Development Campaign (FCRD)/Fuel Resources Program, Office of Nuclear Energy, U.S. Department of Energy (USDOE). Experimental work of S.J.-P. was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division (ERKCC08). Experimental work by B.A., Q.S., and S.M. was supported by the DOE Office of Nuclear Energy’s Nuclear Energy University Program (Grant No. DE-NE0008281). B.A. and S.M. would like to thank Dr. Eric J. Werner at University of Tampa for use of the ICP-OES instrument.