Two-dimensional correlation analysis of nuclear magnetic resonance metabonomics data
1Pfizer, Analytical Research and Development, Groton, Connecticut 06340, USA. slsasic@yahoo.com
Applied Spectroscopy
|August 16, 2008
Summary
Two-dimensional (2D) correlation analysis revealed changes in rat urine metabonomics spectra during induced vasculitis. This technique effectively identified sample groups and process endpoints in preclinical safety studies.
Area of Science:
- Metabonomics
- Spectroscopy
- Preclinical Safety Assessment
Background:
- Vasculitis induction in rats is a critical preclinical safety evaluation.
- Nuclear magnetic resonance (NMR) metabonomics generates complex spectral data.
- Two-dimensional (2D) correlation analysis offers advanced spectral data interpretation.
Purpose of the Study:
- To apply 2D correlation analysis to NMR metabonomics spectra of rat urine.
- To identify spectral changes associated with induced vasculitis.
- To evaluate the utility of 2D correlation analysis for preclinical safety studies.
Main Methods:
- Collected rat urine samples during induced vasculitis.
- Performed 2D correlation analysis (covariance and correlation coefficient maps) on binned and raw NMR spectra.
- Analyzed spectral data at resolutions of 0.04 and 0.001 ppm.
Main Results:
- Identified good correlation among major peaks in binned spectra.
- Sample-sample 2D correlation maps distinguished two sample groups.
- Raw spectra revealed complex features, including butterfly-like patterns in covariance maps, with fewer significant coefficients in correlation maps.
- Clustering of late-stage samples was observed in sample-sample covariance maps for both binned and raw data.
Conclusions:
- 2D correlation analysis is effective for analyzing NMR metabonomics data in preclinical safety studies.
- Covariance maps, particularly for raw spectra, provide valuable insights into spectral changes.
- The study highlights the importance of spectral data resolution and alignment in 2D correlation analysis.
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