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Enantiomer separation by capillary electrochromatography on a cyclodextrin-modified monolith.

D Wistuba·V Schurig
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Abstract

A chiral monolithic stationary phase was prepared by packing a capillary with bare porous silica and sintering the silica bed at high temperature. The resulting silica monolith was polymer-coated with Chirasil-Dex, a permethylated beta-cyclodextrin covalently linked via an octamethylene spacer to dimethylpolysiloxane. Subsequently, Chirasil-Dex was thermally immobilized on the silica support and a chiral monolith of very high stability (30 kV, more than 400 bar pressure) was obtained. The enantiomer separation of various chiral compounds by monolithic (rod) capillary electrochromatography (rod-CEC) was feasible. This method was compared with capillary liquid chromatography (LC) in a single-column mode using unified equipment. About two to three times higher efficiency was found in the rod-CEC mode as compared to rod-LC. The influence of pressure-driven flow support on efficiency, resolution, elution time and baseline stability was investigated. The amount and nature of organic modifier strongly influences efficiency and resolution.

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BarbituratesCarbohydrate ConformationCarbohydrate SequenceCyclodextrinsElectrophoresis, CapillaryHexobarbitalMolecular Sequence DataSiloxanesStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov't

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D Wistuba, V Schurig. 2000. Enantiomer separation by capillary electrochromatography on a cyclodextrin-modified monolith.. https://doi.org/10.1002/1522-2683(20000901)21%3A15%3C3152%3A%3Aaid-elps3152%3E3.0.co%3B2-l

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