Nanopore discrimination of rare earth elements.
Wen Sun1,2, Yunqi Xiao1,2, Kefan Wang1,2
1State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
Nature Nanotechnology
|February 10, 2025
Summary
This study introduces a novel nanopore sensing strategy using dual ligands to identify all 16 rare earth elements (REEs). Machine learning accurately distinguishes REEs by their unique nanopore blockage patterns, aiding geological exploration.
Area of Science:
- Nanotechnology
- Analytical Chemistry
- Materials Science
Background:
- Rare earth elements (REEs) are critical strategic resources due to their unique properties.
- The similar physiochemical properties of REEs pose significant challenges for their identification and separation.
- Existing methods for REE analysis are often complex and time-consuming.
Purpose of the Study:
- To develop a novel, highly accurate method for identifying individual rare earth elements.
- To leverage single-molecule nanopore sensing for REE discrimination.
- To apply this method for analyzing real-world geological samples.
Main Methods:
- Engineering a Mycobacterium smegmatis porin A nanopore with a nitrilotriacetic acid ligand.
- Introducing a secondary ligand, Nα,Nα-bis(carboxymethyl)-L-lysine hydrate (ANTA), to create a dual-ligand sensing system.
- Utilizing machine learning algorithms to analyze nanopore event data for REE identification.
Main Results:
- The dual-ligand nanopore system generated characteristic three-level blockage transitions for different REE(III) ions.
- A clear periodicity in nanopore events indicated the lanthanide contraction effect at the single-molecule level.
- All 16 naturally occurring REE(III)s were identified with high accuracy using this method, including analysis of bastnaesite samples.
Conclusions:
- The developed dual-ligand nanopore strategy offers a powerful tool for discriminating and identifying individual rare earth elements.
- This approach demonstrates the lanthanide contraction effect in a single-molecule regime.
- The method shows promise for applications in geological exploration and resource analysis.
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