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Deblonde GJP, Morrison K, Mattocks JA, Cotruvo JA, Zavarin M, Kersting AB. Impact of a Biological Chelator, Lanmodulin, on Minor Actinide Aqueous Speciation and Transport in the Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20830-20843. [PMID: 37897703 DOI: 10.1021/acs.est.3c06033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/30/2023]
Abstract
Minor actinides are major contributors to the long-term radiotoxicity of nuclear fuels and other radioactive wastes. In this context, understanding their interactions with natural chelators and minerals is key to evaluating their transport behavior in the environment. The lanmodulin family of metalloproteins is produced by ubiquitous bacteria and Methylorubrum extorquens lanmodulin (LanM) was recently identified as one of nature's most selective chelators for trivalent f-elements. Herein, we investigated the behavior of neptunium, americium, and curium in the presence of LanM, carbonate ions, and common minerals (calcite, montmorillonite, quartz, and kaolinite). We show that LanM's aqueous complexes with Am(III) and Cm(III) remain stable in carbonate-bicarbonate solutions. Furthermore, the sorption of Am(III) to these minerals is strongly impacted by LanM, while Np(V) sorption is not. With calcite, even a submicromolar concentration of LanM leads to a significant reduction in the Am(III) distribution coefficient (Kd, from >104 to ∼102 mL/g at pH 8.5), rendering it even more mobile than Np(V). Thus, LanM-type chelators can potentially increase the mobility of trivalent actinides and lanthanide fission products under environmentally relevant conditions. Monitoring biological chelators, including metalloproteins, and their biogenerators should therefore be considered during the evaluation of radioactive waste repository sites and the risk assessment of contaminated sites.
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Affiliation(s)
- Gauthier J-P Deblonde
- Physical and Life Sciences Directorate, Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
- Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Keith Morrison
- Physical and Life Sciences Directorate, Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
- Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Joseph A Mattocks
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Joseph A Cotruvo
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Mavrik Zavarin
- Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Annie B Kersting
- Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
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Moll H, Barkleit A, Frost L, Raff J. Curium(III) speciation in the presence of microbial cell wall components. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 227:112887. [PMID: 34649137 DOI: 10.1016/j.ecoenv.2021.112887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Trivalent actinides such as Cm(III) are able to strongly interact with microbes and especially with bacterial cell walls. However, detailed knowledge of the influence of different cell wall components is somewhat lacking. For this investigation, we studied the formation of aqueous Cm(III) complexes with cell wall components (e.g., lipopolysaccharide, peptidoglycan, and plasma membranes) using time-resolved laser-induced fluorescence spectroscopy (TRLFS). For all systems, two specific Cm(III) complexes with the biomacromolecules were observed as a function of pH. Specifically, Cm(III) was found to bind to phosphate and carboxyl groups present in the structure of the biomacromolecules. Stability constants and luminescence parameters of the specific Cm(III) complexes were determined and are presented. The pH of the surrounding aqueous solution, the plasma membrane concentration, and proteins included in the crude plasma membrane fraction were found to significantly impact the complexation of Cm(III). The Cm(III) luminescence spectra with plasma membranes, cell wall polymers, as well as Gram-negative (Sporomusa sp. MT-2.99 and Pseudomonas fluorescens) and Gram-positive (Paenibacillus sp. MT-2.2) bacteria will be explained by linear combination fitting using the investigated components.
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Affiliation(s)
- Henry Moll
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany.
| | - Astrid Barkleit
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Laura Frost
- JEN Jülicher Entsorgungsgesellschaft für Nuklearanlagen mbH, Wilhelm - Johnen - Straße, 52428 Jülich, Germany
| | - Johannes Raff
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
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Selective adsorption of a new depressant Na2ATP on dolomite: Implications for effective separation of magnesite from dolomite via froth flotation. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117278] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Bader M, Moll H, Steudtner R, Lösch H, Drobot B, Stumpf T, Cherkouk A. Association of Eu(III) and Cm(III) onto an extremely halophilic archaeon. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:9352-9364. [PMID: 30721439 DOI: 10.1007/s11356-019-04165-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/03/2019] [Indexed: 06/09/2023]
Abstract
In addition to geological, geochemical, and geophysical aspects, also, microbial aspects have to be taken into account when considering the final storage of high-level radioactive waste in a deep geological repository. Rock salt is a potential host rock formation for such a repository. One indigenous microorganism, that is, common in rock salt, is the halophilic archaeon Halobacterium noricense DSM15987T, which was used in our study to investigate its interactions with the trivalent actinide curium and its inactive analogue europium as a function of time and concentration. Time-resolved laser-induced fluorescence spectroscopy was applied to characterize formed species in the micromolar europium concentration range. An extended evaluation of the data with parallel factor analysis revealed the association of Eu(III) to a phosphate compound released by the cells (F2/F1 ratio, 2.50) and a solid phosphate species (F2/F1 ratio, 1.80). The association with an aqueous phosphate species and a solid phosphate species was proven with site-selective TRLFS. Experiments with Cm(III) in the nanomolar concentration range showed a time- and pCH+-dependent species distribution. These species were characterized by red-shifted emission maxima, 600-602 nm, in comparison to the free Cm(III) aqueous ion, 593.8 nm. After 24 h, 40% of the luminescence intensity was measured on the cells corresponding to 0.18 μg Cm(III)/gDBM. Our results demonstrate that Halobacterium noricense DSM15987T interacts with Eu(III) by the formation of phosphate species, whereas for Cm(III), a complexation with carboxylic functional groups was also observed.
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Affiliation(s)
- Miriam Bader
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden - Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Henry Moll
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden - Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Robin Steudtner
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden - Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Henry Lösch
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden - Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Björn Drobot
- Max Planck Institute of Molecular Cell Biology and Genetics, Tang Lab, Pfotenhauerstrasse 108, 01307, Dresden, Germany
| | - Thorsten Stumpf
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden - Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Andrea Cherkouk
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden - Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany.
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Bauer N, Panak PJ. Influence of carbonate on the complexation of Cm(iii) with human serum transferrin studied by time-resolved laser fluorescence spectroscopy (TRLFS). NEW J CHEM 2015. [DOI: 10.1039/c4nj01877j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The influence of carbonate on the complexation of Cm(iii) with transferrin is investigated using TRLFS. The results prove directly that carbonate acts as a synergistic anion for Cm(iii) complexation with transferrin.
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Affiliation(s)
- Nicole Bauer
- Karlsruhe Institute of Technology (KIT)
- Campus North
- Institute for Nuclear Waste Disposal (INE)
- 76021 Karlsruhe
- Germany
| | - Petra J. Panak
- Karlsruhe Institute of Technology (KIT)
- Campus North
- Institute for Nuclear Waste Disposal (INE)
- 76021 Karlsruhe
- Germany
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Bauer N, Fröhlich DR, Panak PJ. Interaction of Cm(iii) and Am(iii) with human serum transferrin studied by time-resolved laser fluorescence and EXAFS spectroscopy. Dalton Trans 2014; 43:6689-700. [DOI: 10.1039/c3dt53371a] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Laser spectrochemical characterization of semen. Talanta 2012; 99:140-5. [DOI: 10.1016/j.talanta.2012.05.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 05/17/2012] [Accepted: 05/18/2012] [Indexed: 11/17/2022]
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Moll H, Brendler V, Bernhard G. Aqueous curium(III) phosphate species characterized by time-resolved laser-induced fluorescence spectroscopy. RADIOCHIM ACTA 2011. [DOI: 10.1524/ract.2011.1878] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The formation of aqueous Cm(III) phosphate complexes was studied at room temperature by time-resolved laser-induced fluorescence spectroscopy (TRLFS) in 0.1 M NaClO4 solutions. The experiments were perfomed at a fixed total Cm(III) concentration of 3 × 107 or 2 × 108 M by varying the phosphoric acid concentration (3 × 105–0.1 M) and the pH (1.4–6.0). The red shift of the excitation and emission spectra, as well as the increase of luminescence lifetimes clearly showed the influence of phosphate on the aqueous Cm(III) speciation. In acidic phosphate solutions ([H3PO4] ≤0.1 M, pH 1.4–2.6) an increase in luminescence intensity was detected due to complexation with H2PO4
−. At [H3PO4] ≥4 × 104 M and between pH 4.0 and 6.0 in general a decrease in luminescence intensity affiliates the complexation with HPO4
2−. Two Cm(III)-phosphate complexes could be identified from the emission data, CmH2PO4
2+ and CmHPO4
+, having peak maxima at 599.6 and 600.8 nm, respectively. TRLFS in combination with ultra-filtration (1 kD) showed that the formation of CmHPO4
+ is accompanied by the generation of Cm(III)-phosphate colloids especially at [H3PO4] ≥0.002 M and pH ≥ 5. Cm(III)-phosphate colloids formed at pH 5 and 6 are characterized by an emission maximum at 603.1 nm. Based on the factor analysis of the emission data the stability constants of the two complexes were calculated to be log β
121 = 20.23 ± 0.13 and log β
111 = 16.54 ± 0.80 at an ionic strength of 0.1 M (NaClO4).
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Affiliation(s)
| | - V. Brendler
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiochemistry, Dresden, Deutschland
| | - Gert Bernhard
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiochemistry, Dresden, Deutschland
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Heller A, Rönitz O, Barkleit A, Bernhard G, Ackermann JU. Complexation of europium(III) with the zwitterionic form of amino acids studied with ultraviolet-visible and time-resolved laser-induced fluorescence spectroscopy. APPLIED SPECTROSCOPY 2010; 64:930-935. [PMID: 20719058 DOI: 10.1366/000370210792081127] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The complex formation of europium(III) with the zwitterionic form of amino acids (alanine, phenylalanine, and threonine) has been studied in aqueous solution. Measurements were performed at I = 0.1 M (NaCl/NaClO(4)), room temperature, and trace metal concentrations in the range of pH 2 to 8 using ultraviolet-visible (UV-Vis) and time-resolved laser-induced fluorescence spectroscopy (TRLFS). While complexation leads to a significant luminescence enhancement in the emission spectrum of the metal ion, absorption in the UV-Vis spectrum of the amino acid (AA) decreases. As zwitterionic species (AAH), all three ligands form weak complexes with 1:1 stoichiometry and a general formula of EuAAH(3+) with the metal. The complex stability constants were determined to be log K approximately 1 for all complexes, indicating the negligible contribution of the amino acid side chain to the complex formation reaction.
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Affiliation(s)
- Anne Heller
- Institute of Radiochemistry, Forschungszentrum Dresden-Rossendorf e. V., P.O. Box 510119, Dresden 01314, Germany.
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Andreev G, Budantseva N, Sokolova M, Tananaev I, Myasoedov B. Interaction of transuranium elements with biologically important ligands: structural and spectroscopic evidence for nucleotide coordination to plutonium. Inorg Chem 2010; 48:2343-5. [PMID: 19267495 DOI: 10.1021/ic802053s] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first complex of a transuranium element (tetravalent plutonium) with nucleotide (deoxycytidinemonophosphate, dCMP) was synthesized and structurally characterized. The crystal structure of [Pu(4)(NO(3))(8)(HdCMP)(4)(H(2)O)(8)](NO(3))(4).2H(2)O consists of complex cations [Pu(4)(NO(3))(8)(HdCMP)(4)(H(2)O)(8)](4+), NO(3)(-) anions, and water molecules. There are two crystallographically independent Pu atoms in the structure, both having similar surroundings. Each of the Pu atoms is coordinated by three O atoms of phosphate groups belonging to three different (HdCMP)(-) anions, two bidentate nitrate anions, and two water molecules. The crystal structure is confirmed by IR and UV/vis/near-IR spectroscopic data.
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Affiliation(s)
- Grigory Andreev
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences, 31 Leninskiy pr., Moscow 119991, Russia.
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Balasubramanian K, Cao Z. Spectroscopic Properties and Potential Energy Surfaces for Curium Hydrides: CmH 2, CmH 2+, CmH, and CmH +. J Phys Chem A 2009; 113:12512-24. [DOI: 10.1021/jp903795q] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Balasubramanian
- College of Science, California State University, East Bay, Hayward, California 94542, Chemistry and Material Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, and Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
| | - Zhiji Cao
- College of Science, California State University, East Bay, Hayward, California 94542, Chemistry and Material Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, and Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
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Cao Z, Balasubramanian K, Calvert MG, Nitsche H. Solvation Effects on Isomeric Preferences of Curium(III) Complexes with Multidentate phosphonopropionic Acid Ligands: CmH2PPA2+ and CmHPPA+ Complexes. Inorg Chem 2009; 48:9700-14. [DOI: 10.1021/ic901054h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhiji Cao
- College of Science, California State University, East Bay, Hayward, California 94542
| | - K. Balasubramanian
- College of Science, California State University, East Bay, Hayward, California 94542
- Chemistry and Material Science Directorate Lawrence Livermore National Laboratory Livermore, California 94550
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Michael G. Calvert
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
- Department of Chemistry, University of California, Berkeley, California 94720
| | - Heino Nitsche
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
- Department of Chemistry, University of California, Berkeley, California 94720
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Complexation study of europium(III) and curium(III) with urea in aqueous solution investigated by time-resolved laser-induced fluorescence spectroscopy. Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2008.06.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Moll H, Glorius M, Bernhard G. Curium(III) Complexation with Desferrioxamine B (DFO) Investigated Using Fluorescence Spectroscopy. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2008. [DOI: 10.1246/bcsj.81.857] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Glorius M, Moll H, Bernhard G. Complexation of curium(III) with hydroxamic acids investigated by time-resolved laser-induced fluorescence spectroscopy. Polyhedron 2008. [DOI: 10.1016/j.poly.2008.04.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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17
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Complexation of uranium(VI) with aromatic acids such as hydroxamic and benzoic acid investigated by TRLFS. J Radioanal Nucl Chem 2008. [DOI: 10.1007/s10967-007-7082-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Moll H, Johnsson A, Schäfer M, Pedersen K, Budzikiewicz H, Bernhard G. Curium(III) complexation with pyoverdins secreted by a groundwater strain of Pseudomonas fluorescens. Biometals 2007; 21:219-28. [PMID: 17653625 DOI: 10.1007/s10534-007-9111-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 07/13/2007] [Indexed: 10/23/2022]
Abstract
Pyoverdins, bacterial siderophores produced by ubiquitous fluorescent Pseudomonas species, have great potential to bind and thus transport actinides in the environment. Therefore, the influence of pyoverdins secreted by microbes on the migration processes of actinides must be taken into account in strategies for the risk assessment of potential nuclear waste disposal sites. The unknown interaction between curium(III) and the pyoverdins released by Pseudomonas fluorescens (CCUG 32456) isolated from the granitic rock aquifers at the Aspö Hard Rock Laboratory (Aspö HRL), Sweden, is the subject of this paper. The interaction between soluble species of curium(III) and pyoverdins was studied at trace curium(III) concentrations (3 x 10(-7)M) using time-resolved laser-induced fluorescence spectroscopy (TRLFS). Three Cm(3+)-P. fluorescens (CCUG 32456) pyoverdin species, M(p)H(q)L(r), could be identified from the fluorescence emission spectra, CmH(2)L(+), CmHL, and CmL(-), having peak maxima at 601, 607, and 611 nm, respectively. The large formation constants, log beta(121 )= 32.50 +/- 0.06, log beta(111) = 27.40 +/- 0.11, and log beta(101) = 19.30 +/- 0.17, compared to those of other chelating agents illustrate the unique complexation properties of pyoverdin-type siderophores. An indirect excitation mechanism for the curium(III) fluorescence was observed in the presence of the pyoverdin molecules.
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Affiliation(s)
- Henry Moll
- Institute of Radiochemistry, Forschungszentrum Dresden-Rossendorf, Dresden, Germany.
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Moll H, Bernhard G. Complex formation of curium(III) with amino acids of different functionalities:L-threonine andO-phospho-L-threonine. J COORD CHEM 2007. [DOI: 10.1080/00958970701194058] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Henry Moll
- a Institute of Radiochemistry , Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
| | - Gert Bernhard
- a Institute of Radiochemistry , Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
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Yang T, Bursten BE. Speciation of the Curium(III) Ion in Aqueous Solution: A Combined Study by Quantum Chemistry and Molecular Dynamics Simulation. Inorg Chem 2006; 45:5291-301. [PMID: 16813391 DOI: 10.1021/ic0513787] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structures of aquo complexes of the curium(III) ion have been systematically studied using quantum chemical and molecular dynamics (MD) methods. The first hydration shell of the Cm3+ ion has been calculated using density functional theory (DFT), with and without inclusion of the conductor-like polarizable continuum medium (CPCM) model of solvation. The calculated results indicate that the primary hydration number of Cm3+ is nine, with a Cm-O bond distance of 2.47-2.48 A. The calculated bond distances and the hydration number are in excellent agreement with available experimental data. The inclusion of a complete second hydration shell of Cm3+ has been investigated using both DFT and MD methods. The presence of the second hydration shell has significant effects on the primary coordination sphere, suggesting that the explicit inclusion of second-shell effects is important for understanding the nature of the first shell. The calculated results indicate that 21 water molecules can be coordinated in the second hydration shell of the Cm3+ ion. MD simulations within the hydrated-ion model suggest that the second-shell water molecules exchange with the bulk solvent with a lifetime of 161 ps.
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Affiliation(s)
- Tianxiao Yang
- Department of Chemistry, Ohio State University, Columbus, Ohio 43210, USA
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