Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

Chemistry

First Advisor's Name

Francisco Fernandez-Lima

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Piero Gardinali

Second Advisor's Committee Title

Committee member

Third Advisor's Name

J. Martin E. Quirke

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Berrin Tansel

Fourth Advisor's Committee Title

Committee member

Fifth Advisor's Name

John Berry

Fifth Advisor's Committee Title

Committee member

Keywords

TIMS, FT-ICR MS, Complex mixtures, High resolution ion mobility spectrometry, endocrine disruptors, crude oil, petroleum, polyaromatic hydrocarbons, PAHs, APLI, Atmospheric pressure laser ionization, molecular modeling, isomer separations

Date of Defense

9-18-2017

Abstract

Analytical Characterization of complex mixtures, such as crude oil, environmental samples, and biological mixtures, is challenging because of the large diversity of molecular components. Mass spectrometry based techniques are among the most powerful tools for the separation of molecules based on their molecular composition, and the coupling of ion mobility spectrometry has enabled the separation and structural elucidation using the tridimensional structure of the molecule. The present work expands the ability of analytical chemists by furthering the development of IMS-MS instrumentation by coupling Trapped Ion Mobility Spectrometry to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (TIMS-FT-ICR MS). The TIMS-FT-ICR MS platform combines the high-resolution separation of TIMS, which has mobility resolving powers up to 400, and ultra-high mass resolution of FT-ICR MS, with mass resolving power over 1,000,000. This instrumentation allows the assignment of exact chemical composition for compounds in a complex mixture, as well as measurement of the collision cross-section of the molecule. Herein, the principles of the TIMS separation and its coupling to FT-ICR MS are described, as well as how the platform can be applied to targeted analysis of molecules, and untargeted characterization of complex mixtures.

Molecular standards were analyzed by TIMS-MS in order to develop a computational workflow that can be utilized to elucidate molecular structure, using the measured collision cross-section of the ion. This workflow enabled identification of structural, cis/trans isomers, and chelated molecules and provides the basis for unsupervised structural elucidation of a complex mixture, and in particular for the elucidation of hydrocarbons from fossil fuels. In summary, this work presents the coupling of TIMS-FT-ICR MS and provides examples of applications as a proof of concept of the potential of this platform for solving complex analytical challenges.

Identifier

FIDC004019

ORCID

0000-0002-5298-289X

Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

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