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Method development and instrument modification in Fourier transform mass spectrometry, and the study of substituent effects in the mass spectra of a series of N-(substituted benzalamino)phthalimides
Abstract
Chapter 1 presents a review on Fourier transform mass spectrometry: it's features, principals, capabilities and limitations. The review of this technique is presented in the form of a tutorial, starting with the advantages inherent in Fourier transform mass spectrometry and proceeding to the basic theory of ion formation, excitation and detection. The review then advances to discuss the application of non-routine experiments and analysis. Chapters 2 and 3 are concerned with our belief that Fourier transform mass spectrometry is capable of becoming a routine analytical method. Chapter 2 approaches the quantitative analysis of gas chromatography FTMS with an improved GC/FTMS interface. The pulsed-cold trap/pulsed valve interface described herein has been shown to improve the duty-cycle of GC/FTMS to approximately 1:1. Ultimately, this has led to the detection of toluene at levels approaching that of the detection limits of GC/MS via magnetic-sector mass spectrometers and with mass resolutions beyond those attained with GC/MS using sector instrument. Chapter 3 approaches the aspect of analytical FTMS from the point of qualitative analysis, or more accurately, the determination of elemental formula via high resolution mass analysis. The incorporation of a temporal dynamic-trapping event, the rf-only-event, in the normal FTMS sequence is shown to efficiently trap and focus ions which have been excited to large radial orbits. This dynamic trapping, or cooling, event is proposed to aid in allowing high resolution detection of biomolecules produced from energetic ionization events such as electrospray and matrix-assisted laser desorption. Chapter 4 describes the effect of substituents on the mass spectra of a series of N-(substitutedbenzalamino)phthalimdes. These effects on the predominate fragmentation pathway of the molecular ion has been used to ascertain the ionization energy of the enol-isomer of the phthalimide ion. The formation of an ion-neutral complex has been proposed to explain the formation of the protonated phthalimide molecule formed in the fragmentation of a number of the substituted compounds.
Subject Area
Analytical chemistry|Biochemistry
Recommended Citation
Jacoby, Cliffton Bradley, "Method development and instrument modification in Fourier transform mass spectrometry, and the study of substituent effects in the mass spectra of a series of N-(substituted benzalamino)phthalimides" (1993). ETD collection for University of Nebraska-Lincoln. AAI9331422.
https://digitalcommons.unl.edu/dissertations/AAI9331422