Synthesis and characterization of a novel, single-isomer, hydrophobic, anionic, charged cyclodextrin for capillary electrophoresis /
anionic charged cyclodextrin, the sodium salt of heptakistz.3-dimethyl-6-sulfatol-p-cyclodextrin (HDMS-P-CD), has been successfully synthesized on a large scale using protection group chemistry. This new material was characterized by [IH] and [13C] NMR, Electrospray-lonization MS and indirect UV det...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1998.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=732838181&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | anionic charged cyclodextrin, the sodium salt of heptakistz.3-dimethyl-6-sulfatol-p-cyclodextrin (HDMS-P-CD), has been successfully synthesized on a large scale using protection group chemistry. This new material was characterized by [IH] and [13C] NMR, Electrospray-lonization MS and indirect UV detection capillary electrophoresis (CE). [HDMS-/-CD] can be used as a choral resolving agent in CE. [HDMS-P-CD] has been used in aqueous background electrolytes (BE), both at low and high pH, for the separation of a variety of neutral, acidic, basic and zwitterionic analyses. Separation sensitivities were determined from the measured analyte effective mobilities at different [HDMS-P-CD] concentrations. Complexation constants were obtained for some neutral analyses by fitting the selectivity values to the theoretically derived selectivity equation of the Charged Resolving Migration Model (CHARM model) in low pH BEs. It has been found that the complication between [HDMS-P-CD] and the neutral analyses is very weak. The experimental results showed that the effective mobility and the selectivity changes closely follow the predictions of the CHARM model. Separation selectivity for neutral analyses decreases when the HDMS-P-CD concentration is increased. The separation selectivity for charged analyses can increase, decrease or pass a maximum as the [HDMS-O-CD] concentration is varied. Three factors, separation selectivity, dimensionless electroosmotic flow and effective charge influence the extent of peak resolution. Chiral separations with [HDMS-SCD] were also studied in methanol-water BEs and pure methanol BEs at low pH. The introduction of methanol improved the solubility of the analyte in the BEs, but decreased the effective mobility of the analyte. The behavior of [HDMS-P-CD] in methanol-water and pure methanol BEs also followed the predictions of the CHARM model. A variety of choral analyses, neutral, weak acids, weak bases and zwitterions, were successfully separated in methanol-containing BEs. The migration order of the cationic analyses could be reversed by varying the concentration of both [HDMS-P-CD] and methanol, as predicted by the CHARM model. The separations for weak bases were fast, but those for the neutral analyses were slow. Only weak base analyses could be resolved in pure methanol BEs. |
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| Item Description: | Vita. "Major Subject: Chemistry". |
| Physical Description: | xii, 143 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references: pages 125-130. |