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Detection of highly overlapping peaks via adaptive apodization
Ruis MacDonald1, Stanislav Sokolenko1
1Process Engineering and Applied Science, Dalhousie University, Sexton Campus, 5273 DaCosta Row, PO Box 15000, Halifax NS B3H 4R2, Canada.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|November 21, 2021
Summary
This study introduces an adaptive apodization method for improved nuclear magnetic resonance (NMR) peak detection, especially for overlapping signals. The open-source rnmrfind package enhances spectral analysis accuracy and reduces false positives.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Computational Chemistry
Background:
- Accurate peak detection is crucial for nuclear magnetic resonance (NMR) spectroscopy tasks like compound identification and spectral analysis.
- Existing peak detection methods struggle with spectral overlap, negatively impacting downstream data processing and analysis.
- Overlapping peaks in NMR spectra present a significant challenge for accurate signal quantification and interpretation.
Purpose of the Study:
- To develop and present an adaptive apodization strategy for enhanced detection of highly overlapping peaks in NMR spectra.
- To introduce the open-source R package 'rnmrfind' that implements this novel peak detection method.
- To demonstrate the improved performance of the proposed method compared to existing NMR data processing tools.
Main Methods:
- Utilized adaptive apodization incorporating sensitivity and resolution enhancement, with parameters derived directly from spectral data.
- Implemented data-driven parameter calculations for sensitivity enhancement (regions of interest) and resolution enhancement (peak separation).
- Incorporated peak width limitations to minimize false positive detections and refined parameters for application-specific tuning.
Main Results:
- The adaptive apodization strategy significantly improves the detection of overlapping NMR peaks.
- The 'rnmrfind' R package provides effective peak detection with minimal false positives using default parameters.
- Comparative analysis against 'rNMR' and 'speaq' packages on 1H NMR spectra showed superior peak resolution.
Conclusions:
- The proposed adaptive apodization method offers a robust solution for overcoming spectral overlap challenges in NMR data processing.
- The 'rnmrfind' package provides an accessible and effective tool for researchers, enhancing the accuracy of NMR-based analyses.
- This approach demonstrates potential for broader application in various NMR-related scientific disciplines requiring precise peak identification.
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