## Abstract Crosslinked polysiloxane stationary phases were prepared on sodaβlime glass capillaries and applied to the separation of polynuclear aromatic hydrocarbons and of phthalates in reversedphase liquid chromatography. Preparation procedures and chromatographic performance of these columns ar
Separation of steroid isomers using a liquid crystalline polysiloxane stationary phase in capillary supercritical fluid chromatography
β Scribed by Huey-Ching Chang; Karin E. Markides; Jerald S. Bradshaw; Milton L. Lee
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 384 KB
- Volume
- 1
- Category
- Article
- ISSN
- 1040-7685
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β¦ Synopsis
A liquid crystalline biphenylcarboxylate ester polysiloxane stationary phase was used to study the effect of solute structure on retention for the separation of isomeric steroids in capillary supercritical fluid chromatography. It was determined that the retention mechanism is related to solute molecular shape rather than to properties such as volatility or polarity. The elution order of isomeric androstanes and estrogens could be correlated with the planarity of molecules: more-planar molecules were retained longer on the column. The resolution of steroid isomers was improved significantly using the liquid crystalline stationary phase when compared with results obtained using other stationary phases.
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## Abstract A new kind of side chain liquid crystalline polysiloxane containing a crown ether with a longer spacer (PSCβ11) has been prepared and coated on a fused silica capillary column. The main chromaβtographic characteristics including efficiency, polarity, and selectivity have been examined.
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