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Quantitative Trace Analysis of Dilute Mixtures Using a Benchtop NMR System with SABRE Hyperpolarization
Bono O Jimmink1, Mattia Negroni1, Thom B Posthumus1
1Magnetic Resonance Research Center, Institute for Molecules and Materials, Radboud University, 6525AJ Nijmegen, The Netherlands.
Analytical Chemistry
|May 19, 2025
Summary
Signal Amplification By Reversible Exchange (SABRE) hyperpolarization now works at micromolar concentrations using benchtop NMR. This breakthrough enables sensitive quantification in a wider range of applications.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Hyperpolarization Techniques
- Analytical Chemistry
Background:
- Benchtop NMR spectrometers offer cost-effectiveness and portability but suffer from low sensitivity.
- Nuclear spin hyperpolarization techniques significantly enhance NMR signal sensitivity.
- Signal Amplification By Reversible Exchange (SABRE) uses para-hydrogen (pH2) for hyperpolarization.
Purpose of the Study:
- To extend the application of SABRE hyperpolarization to micromolar concentration ranges.
- To demonstrate the feasibility of SABRE on a low-field (1 T) benchtop NMR spectrometer.
- To enable sensitive quantification at lower sample concentrations.
Main Methods:
- Utilized Signal Amplification By Reversible Exchange (SABRE) hyperpolarization.
- Employed para-hydrogen (pH2) as the polarization source.
- Performed measurements on a 1 T benchtop NMR spectrometer with samples at micromolar concentrations.
Main Results:
- Achieved successful SABRE hyperpolarization of a mixture at micromolar concentrations.
- Demonstrated a linear relationship between hyperpolarized signal intensity and concentration.
- Confirmed the stability and reliability of the approach for low-concentration measurements.
Conclusions:
- SABRE hyperpolarization can be effectively applied to micromolar concentrations using benchtop NMR.
- This advancement overcomes previous sensitivity limitations for benchtop NMR applications.
- The developed method allows for stable and accurate quantification at the micromolar level.
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