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Accounting for gradient non-uniformity in spatially-encoded diffusion-ordered NMR spectroscopy
Benjamin Lorandel1, Rituraj Mishra1, Oksana Cazimajou1
1Nantes Université, CNRS, CEISAM UMR6230, F-44000 Nantes, France.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|September 14, 2023
Summary
This study introduces methods to correct for non-uniform magnetic field gradients in Spatially-encoded Diffusion-Ordered NMR Spectroscopy (SPEN DOSY). This improves the accuracy of mixture analysis using SPEN DOSY experiments.
Area of Science:
- Analytical Chemistry
- Nuclear Magnetic Resonance (NMR) Spectroscopy
Background:
- Diffusion-Ordered NMR Spectroscopy (DOSY) is vital for analyzing complex mixtures.
- Spatially-encoded (SPEN) DOSY enables rapid data acquisition in a single scan.
- Current SPEN DOSY analysis assumes uniform magnetic field gradients, which is often inaccurate.
Purpose of the Study:
- To develop and validate methods for correcting magnetic field gradient non-uniformity in SPEN DOSY.
- To enhance the accuracy and reliability of SPEN DOSY experiments.
Main Methods:
- Mapping magnetic field gradients using a stimulated echo (STE) NMR sequence.
- Modifying the calculation of position-dependent effective gradient pulse areas for SPEN DOSY data analysis.
- Validating the developed methods through numerical simulations.
Main Results:
- Successfully mapped field gradients within the NMR probe.
- Implemented a modified data processing model accounting for gradient non-uniformity.
- Numerical simulations confirmed the model's validity.
Conclusions:
- The developed methods accurately account for gradient non-uniformity in SPEN DOSY.
- Inclusion of gradient non-uniformity correction significantly increases the accuracy of SPEN DOSY experiments.
- This advancement improves the quantitative analysis of mixtures using SPEN DOSY.
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