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Advancing quantitative NMR for high-precision isotopic analysis with rnmrfit 2.0
Kathy Sharon Isaac1, Phuong Mai Le2, Theodore Street1
1Department of Process Engineering and Applied Science, Dalhousie University, 5273 DaCosta Row, PO Box 15000, Halifax, B3H 4R2, NS, Canada.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|November 14, 2025
Summary
A new NMR peak-fitting tool, rnmrfit 2.0, enhances isotopic analysis precision. This open-source software offers superior accuracy for determining chemical origins and authenticity.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Isotope Analysis
Background:
- Quantitative Nuclear Magnetic Resonance (NMR) is crucial for isotopic ratio measurements.
- Accurate signal-to-noise separation is vital for reliable peak area quantification in isotopic analysis.
Purpose of the Study:
- To introduce rnmrfit 2.0, an advanced NMR peak-fitting tool for high-precision isotopic analysis.
- To evaluate the impact of spectral processing techniques on peak fitting precision.
Main Methods:
- Development and application of rnmrfit 2.0, featuring semi-global fitting and automated peak region selection.
- Investigation of line broadening, zero filling, and baseline span effects on peak fitting.
- Comparison of rnmrfit 2.0 performance against commercial software (TopSpin, MestReNova).
Main Results:
- Optimal line broadening (1-3 Hz) and zero filling (0.5-1.0) settings were identified, differing from common 13C recommendations.
- rnmrfit 2.0 demonstrated superior precision and trueness, achieving low error rates (0.26% for 2H, 0.16% for 13C).
- The software showed greater robustness and computational efficiency compared to previous versions.
Conclusions:
- rnmrfit 2.0 provides a robust, efficient, and open-source solution for high-precision isotopic analysis.
- The software requires minimal user input, facilitating reliable isotopic quantification.
- Optimal spectral processing parameters are critical for accurate isotopic ratio determination.
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