High performance microcoil NMR probes and applications with LC-MS for bio-sample analysis
Abstract
Like genomics and proteomics, metabolic profiling has immense potential benefits for elucidating cellular activities, drug metabolism, disease prediction and diagnosis. Nuclear Magnetic Resonance (NMR) Spectroscopy and Mass Spectrometry (MS) are two of the best analytical approaches for identifying and quantifying small molecule metabolites. However, only a few hundred out of thousands of endogenous human metabolites are typically detected due to a range of issues, such as limitations in sensitivity, resolution, reproducibility and throughput, and complexity of the biological samples. Thus, to tackle these limitations, this dissertation work presents a combination of approaches, such as microcoil NMR probe instrumentation, sample preparation and NMR/MS experimental/hyphenation techniques with liquid chromatography (LC). Specifically, the work is focused on instrumental designs, and their practical applications focused on simplifying the analytical study by reducing the complexity of the metabolic samples. Developing methods will allow us to determine structures of both known and unknown metabolites by high throughput and high resolution NMR, and at the same time, to detect low concentration metabolites by hyphenated LC-MS. With these motivations in mind, this dissertation provides details on the design and construction of a 20-μL zero-susceptibility solenoidal microcoil NMR probe (with 9-fold more sensitivity enhanced compared to copper-coil microcoil probes), a novel susceptibility-matched plugged microcoil probes (with 20-fold volume efficiency and 10-fold raw sensitivity enhancement compared to conventional probes), a dual volume microcoil flow NMR probe (with 2-fold throughput enhancement), the hyphenation of dual volume probe with Liquid Chromatography-Mass spectrometry (LC-MS) system, and the structural identification of metabolites in biological samples using NMR and LC-MS.
Degree
Ph.D.
Advisors
Raftery, Purdue University.
Subject Area
Analytical chemistry
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