Date of Award

1998

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

First Advisor

Isiah M. Warner

Abstract

The research presented in this dissertation involves the use and characterization of polymerized amino acid based surfactants for the enantiomeric separation of chiral compounds using capillary electrophoresis. The first section, Chapter 1, is an introduction to three topics which are relevant to the work presented in this manuscript. The topics include a brief discussion about chirality and chiral recognition, followed by a description of surfactants and micellar systems. The last part of the introduction pertains to capillary electrophoresis and the use of micellar electrokinetic chromatography for enantiomeric separation of chiral compounds. In Chapter 2, the effect of amino acid order in dipeptide surfactants on the enantiomeric separation of two model atropisomers is reported. The two main dipeptide surfactants used were poly sodium N-undecyl (L,L) valine-leucine and poly sodium N-undecyl (L,L) leucine-valine. Additionally, their similarity and differences from other related surfactants, i.e. poly sodium N-undecyl (L,L) leucine-leucine, poly sodium N-undecyl (L,L) valine-valine, poly sodium N-undecyl L-valine, and poly sodium N-undecyl L-leucine are also discussed. Chapter 3 outlines an investigation of the effect of amino acid order with polymerized dipeptide surfactants in more detail. Fluorescent probe studies were conducted to characterize and compare the hydrophobicity of the microenvironment within the hydrophobic core of the polymeric surfactants. The results of this study lead to a proposed structure of the dipeptide surfactant in solution. In the next chapter, the use of diastereomeric polymerized dipeptide surfactants as a diagnostic tool to gain insight into the preferential site of interaction for various chiral compounds is discussed. In Chapter 5 the results of studies that were performed to determine optimum CE conditions for twelve chiral analytes with eight amino acid based polymerized chiral surfactants are examined. Finally, in Chapter 6 an examination of the effect of several different aspects of polymerized dipeptide surfactants, as they pertain to chiral separations, is discussed. Some aspects of dipeptide surfactants which are discussed include the effect of number and position of chiral centers, amino acid order, and steric factors on the enantiomeric separation of twelve chiral compounds using nineteen polymerized amino acid based surfactants.

ISBN

9780599213463

Pages

247

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