Selective recognition of americium by peptide-based reagents.

Area of Science:

• Nuclear chemistry
• Materials science
• Biotechnology

Background:

• Separating lanthanides from minor actinides (americium, curium) is vital for nuclear waste recycling.
• Similar chemical properties and ionic radii of these elements pose significant separation challenges.
• Current methods often lack the required selectivity and efficiency.

Purpose of the Study:

• To develop a novel peptide-based reagent for selective binding of trivalent actinides over lanthanides.
• To enhance the separation process in nuclear waste treatment.
• To improve the efficiency and selectivity of actinide-lanthanide separation.

Main Methods:

• Modification of a lanthanide-binding tag (LBT) peptide by introducing soft-donor atoms.
• Mutation of asparagine to cysteine at the fifth position of the LBT.
• Functionalization of the modified peptide with a pyridine moiety.
• Utilizing fluorescence spectroscopy to quantify metal-peptide complex dissociation constants.

Main Results:

• The modified peptide reagent demonstrated selective binding of trivalent actinides over trivalent lanthanides.
• A 10-fold selectivity was achieved for americium (Am3+) over neodymium (Nd3+).
• The introduction of soft-donor atoms and pyridine functionalization were key to achieving selectivity.

Conclusions:

• Peptide-based reagents with tailored soft-donor atoms can effectively achieve selective actinide-lanthanide separation.
• This approach offers a promising strategy for improving nuclear waste recycling processes.
• The modified LBT provides a new tool for selective metal ion binding and separation in complex mixtures.