Related Experiment Video
Updated: Mar 5, 2026
12:22
Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films
Published on: November 9, 2015
11.9K
Substructural Components of Organic Colloids from a Pu-Polluted Soil with Implications for Pu Mobilization
Nicole DiDonato1, Chen Xu2, Peter H Santschi2
1Department of Chemistry and Biochemistry, Old Dominion University , Norfolk, Virginia 23529, United States.
Environmental Science & Technology
|March 24, 2017
Summary
Researchers identified novel nitrogen and carboxyl functionalities in soil colloids that strongly bind plutonium (Pu). This discovery advances understanding of plutonium
Area of Science:
- Environmental Chemistry
- Geochemistry
- Analytical Chemistry
Background:
- Soil organic matter at Rocky Flats Environmental Technology Site (RFETS) accumulates plutonium (Pu).
- A specific colloidal subfraction is hypothesized to contain cutin-like structures with hydroxamate functionality, explaining Pu affinity.
Purpose of the Study:
- To further characterize the high plutonium affinity subfraction from contaminated RFETS soil.
- To identify additional substructural components within the Pu-enriched colloidal subfraction.
Main Methods:
- Extraction and purification of the Pu-enriched fraction using ultrafiltration and isoelectric focusing (IEF) electrophoresis.
- Characterization using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICRMS).
Main Results:
- Detection of predominantly low H/C and high double-bond equivalence (DBE) aromatic and condensed aromatic molecular formulas.
- Identification of 66% of formulas within a COO Kendrick mass defect (KMD) homologous series, indicating polycarboxylated structures.
- Increased nitrogen content in purified subfractions correlated with higher Pu concentrations.
Conclusions:
- The study suggests the presence of polycarboxylated aromatic and condensed aromatic formulas, with CHON-type COO KMD formulas being more abundant in Pu-enriched fractions.
- Nitrogen and carboxyl functionalities on aromatic compounds are proposed as key contributors to plutonium chelation in soil colloids.
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