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Preparation of Fungal and Plant Materials for Structural Elucidation Using Dynamic Nuclear Polarization Solid-State NMR
Published on: February 12, 2019
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Ion exchange and binding in selenium remediation materials using DNP-enhanced solid-state NMR spectroscopy
Marco Mais1, Javier Torroba2, Nathan S Barrow2
1School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
Solid State Nuclear Magnetic Resonance
|January 29, 2019
Summary
Dynamic nuclear polarization (DNP) significantly speeds up solid-state NMR for selenium remediation materials. This allows detailed study of how selenate ions bind to polymer fibers, improving water purification methods.
Area of Science:
- Materials Science
- Analytical Chemistry
- Environmental Science
Background:
- Selenium contamination in water poses environmental and health risks.
- Polymer fibers are explored for selenium remediation due to their ion-exchange properties.
- Solid-state Nuclear Magnetic Resonance (NMR) is a powerful tool for characterizing material structures.
Purpose of the Study:
- To investigate selenate-loaded selenium remediation materials based on polymer fibers.
- To assess the utility of dynamic nuclear polarization (DNP) enhanced solid-state NMR for these materials.
- To elucidate the binding interactions between remediated selenate ions and the polymer matrix.
Main Methods:
- Dynamic Nuclear Polarization (DNP) enhanced solid-state NMR spectroscopy.
- Carbon-13 (13C) NMR experiments.
- {1H}-77Se heteronuclear correlation (HETCOR) NMR experiments.
Main Results:
- DNP significantly reduces experiment time for 13C NMR, even with smaller sample sizes.
- Efficient acquisition of {1H}-77Se HETCOR spectra is enabled by DNP.
- The binding nature of selenate ions with the polymer's grafted side chains was investigated.
Conclusions:
- DNP-enhanced solid-state NMR is highly effective for studying selenium remediation materials.
- The method provides crucial insights into the ion-exchange mechanisms involved in selenate binding.
- This research advances the understanding and development of materials for selenium water remediation.
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