Display Full Text | Download Full Text
3.34 MB PDF file

Degree

Doctor of Philosophy, Miami University, Chemistry, 2011.

Abstract

This dissertation describes new statistical analysis methods for nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography/mass spectroscopy (LC/MS) – based metabonomics along with determining if diapers and cotton balls could introduce contamination into newborn babies urine when collecting their urine for metabonomic studies using the “cotton ball in diaper” method of collection. Chapter 1 provides a background of metabonomics along with the advantages and disadvantages of the two analytical techniques used, NMR and LC/MS, along with how the data is analyzed using multivariate data analysis. Chapter 2 develops a decision tree algorithm to determine which buckets in the loadings plot are statistically significant in the principal component analysis (PCA). After the statistical analysis the loadings plot was colored based on a “heat-map” according to the p-score for each loading, which showed how significant the buckets were in the analysis. Based on the significance analysis, the effect size was calculated to allow for the calculation of the study size that is needed for each group in a metabonomics study. Chapter 3 develops a metric for quantification of cluster separation and for assessment of the statistical significance of cluster separation seen in the scores plot of the PCA. Along with this it was shown how Pareto scaling and partial least squares – discriminant analysis (PLS-DA) affected the separation in the scores plot, along with how it affects the loadings plot of a PCA. Chapter 4 investigated the coefficient of variation (CV) of NMR data collected over an eight-month period and how the signal-to-noise (S/N) ratio affected the CV. This study determined that the CV has no relation to the S/N ratio and that the CV must be considered when validating a potential biomarker. Chapter 5 investigates the potential effect of diaper and cotton ball contamination on NMR and LC/MS-based metabonomic studies of urine from newborn babies. It was determined that the diaper could potentially affect a metabonomic study, but when the cotton ball is inserted the chance for contamination decreases. Chapter 6 summarizes the presented research.

Subject Headings

Analytical Chemistry; Biostatistics; Chemistry

Keywords

Metabonomics; Statistical Analysis; Nuclear Magnetic Resonance; Liquid Chromatography; Mass Spectroscopy; NMR; LC/MS

Committee / Advisors

Michael A. Kennedy, PhD (Advisor)
Neil D. Danielson, PhD (Committee Chair)
Carole Dabney-Smith, PhD (Committee Member)
Blanton S. Tolbert, PhD (Committee Member)
Natosha L. Finley, PhD (Committee Member)

Pages

137p.

Document number: miami1312317652
Permalink: http://rave.ohiolink.edu/etdc/view?acc_num=miami1312317652

This ETD has been downloaded 80 times (through March 2013)