• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 추계 총회 및 학술발표회
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• pp.152-155
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• 2004

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1809-1813
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• 2013

Sulfated ${\beta}$-cyclodextrin (SCD)-coated zirconia monolith was used as the chiral stationary phase in capillary electrochromatography for enantiomeric separation of basic chiral compounds. SCD adsorbed on the zirconia surface provided a stable chiral stationary phase in reversed-phase eluents. Retention, chiral selectivity and resolution of a set of six basic chiral compounds were measured in eluents of varying pH, composition of methanol and buffer. Optimum mobile phase condition for the separation of the compounds was found to be methanol content of 30%, buffer concentration of 30 mM and pH of 4.0.

• Bulletin of the Korean Chemical Society
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• 제25권3호
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• pp.377-381
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• 2004

Chiral separation of aryalcohols such as 1-phenyl-propanol, 1-phenyl-2-proanol, and 2-phenyl-1-propanol by capillary electrophoresis has been optimized using the overlapping resolution mapping (ORM) scheme. Three critical parameters of the electrophoretic media, i.e. phosphate concentration, sulfated ${\beta}$-cyclodextrin (CD) concentration and pH, were chosen for optimization. The working ranges were initially presumed by 7 preexperiments. Further optimization was carried out by another seven experiments within the narrow working ranges. From the final overlapping resolution mapping all peak pairs, the area of maximum separations were located. Using the conditions of a point in this area, we found that the target compounds were a baseline separated within 30 min. The maximum separation conditions of arylalcohols were a chiral selector concentration of 5.4%, a phosphate concentration of 28 mM, and a pH of 5.0.

• 분석과학
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• 제17권1호
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• pp.16-22
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• 2004

Inclusion complexes of the p-nitrophenol with ${\beta}$-cyclodextrin (CD), sulfated ${\beta}$-CD, and ${\beta}$-CD polymer cross-linked with epichlorohydrine (EP) were prepared and characterized by Raman spectroscopy. The intensity of vibration peaks of the C-O and C-N at 1284 and $856cm^{-1}$ of the p-nitrophenol in the presence of EP-linked CD polymer was remarkably increased, respectively. The vibration modes at 1284 and $856cm^{-1}$ are assigned to the out-of phase C-C-O stretching mode and the C-N stretching mode, respectively. The vibration peaks at 1284 and $856cm^{-1}$ increased with increasing the content of EP-linked CD polymers, while decreased with increasing the p-nitrophenol content. Furthermore, the vibration mode of the $NO_2$ symmetric stretch at $1344cm^{-1}$ enhanced with increasing the content of p-nitrophenol.

• Macromolecular Research
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• 제14권4호
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• pp.449-455
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• 2006

Ionic cluster mimic, polymer electrolyte membranes were prepared using polymer composites of crosslinked poly(vinyl alcohol) (PVA) with sulfated-${\beta}$-cyclodextrins (${\beta}-CDSO_3H$) or phosphated-${\beta}$-cyclodextrins (${\beta}-CDPO(OH)_2$). When Nafion, developed for a fuel cell using low temperature, polymer electrolyte membranes, is used in a direct methanol fuel cell, it has a methanol crossover problem. The ionic inverted micellar structure formed by micro-segregation in Nafion, known as ionic cluster, is distorted in methanol aqueous solution, resulting in the significant transport of methanol through the membrane. While the ionic structure formed by the ionic sites in either ${\beta}-CDSO_3H$ or ${\beta}-CDPO(OH)_2$ in this composite membrane is maintained in methanol solution, it is expected to reduce methanol transport. Proton conductivity was found to increase in PVA membranes upon addition of ionized cyclodextrins. Methanol permeability through the PVA composite membrane containing cyclodextrins was lower than that of Nafion. It is thus concluded that the structure and fixation of ionic clusters are significant barriers to methanol crossover in direct methanol fuel cells.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.215.1-215.1
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• 2002