Displacement chromatography on cyclodextrin-silica columns /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1990.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | Cyclodextrin silica stationary phases have been shown to be widely applicable for the separation of enantiomers, diastereomers, positional isomers and geometrical isomers. Since the chiral separation factors and loading capacities of cyclodextrin silicas are low, they are not used extensively for preparative separations in the elution mode. Separations in the displacement mode offer, in general, high throughput and purity even when the selectivities are too low for successful preparative gradient elution chromatographic separations. In this dissertation we show how the novel combination of the chiral selectivity of cyclodextrin silica phases and the unique operational principles of displacement chromatography leads to a very efficient preparative chiral separation method. Success of a displacement chromatographic separation depends on the finding of the right displacer and the right experimental conditions. Many of the displacers commonly used in reversed-phase liquid chromatography are unsuitable for cyclodextrin silica stationary phases. Therefore, we have synthesized a series of displacers specifically designed for cyclodextrin silicas; displacers which can be used under broad experimental conditions. A protocol, based on the elution mode separation of the solutes and the adsorption isotherms of the potential displacers, was developed to help find the experimental conditions for the separations. The feasibility of displacement chromatography on cyclodextrin silicas is demonstrated by the separation of geometrical isomers, positional isomers and optically active compounds. Factors that can influence the efficiency of displacement chromatographic separations on cyclodextrin silica columns are discussed. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Chemistry." |
| Physical Description: | xvii, 173 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |