• Analytical Science and Technology
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• v.22 no.4
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• pp.313-318
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• 2009

Liquid chromatographic enantiomer separation of amino alcohols was performed on several chiral columns based on polysaccharide derivatives under the mobile phase conditions containing acid or base additive. The chromatographic parameters were greatly influenced by the nature of the mobile phase containing acid or base additive as well as the used chiral columns. Compared to chromatographic results obtained in the mobile phase containing base additive (0.1% triethylamine), especially, Chiralcel OD showed dramatically enhanced separation factors and resolution factors with reduced capacity factors under the mobile phase condition containing acidic additive (0.1% trifluoroacetic acid). When the mobile phase containing 0.05% trifluoroacetic acid and 0.05% triethylamine was used on Chiralcel OD, the greatest separation factors and resolution factors among all other mobile phase conditions in this study were observed.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.165-166
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• 2002

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.217.2-218
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• 2001

• KSBB Journal
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• v.27 no.3
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• pp.167-171
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• 2012

A convenient liquid chromatographic enantiomer separation of several ${\alpha}$-amino acid esters as benzophenone Schiff base derivatives on covalently immobilized chiral stationary phases (CSPs) derived from polysaccharide derivatives was developed. The benzophenone imine derivatives of ${\alpha}$-amino acid esters were readily prepared by stirring benzophenone imine and the ${\alpha}$-amino acid ester hydrochloride salts in 2-propanol. The chromatographic conditions used on all CSPs were 0.5% or 5% 2-propanol/hexane (V/V) as the mobile phases at 1 mL/min of flow rate and UV 254 nm detection. The performance of Chiralpak IC among all CSPs was superior to that of the other CSPs for resolution of benzophenone imine derivatives of ${\alpha}$-amino acid esters. It is expected that the developed analytical method will be useful for enantiomer resolution of other ${\alpha}$-amino acid esters as benzophenone Schiff base derivatives.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.998-1000
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• 2005

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.341-345
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• 2005

Since it is troublesome to estimate adequate flow rates in four sections of SMB chromatography, a systematic determination of the flow rates has been suggested by using ketoprofen as a model chiral enantiomer. S-ketoprofen. less retained species, was separated from raffinate stream and the variation in its purity was dependent on the changes of the flow rate of section 4 ($Q_4$), the raffinate flow rate ($Q_{raf}$), and the feed flow rate ($Q_{feed}$) under a fixed switch­ing time t$^{\ast}$. When one parameter was changed at the given experimental condition, purities of product were changed and these phenomena has be well explained by the triangle theory.

• Journal of Integrative Natural Science
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• v.9 no.1
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• pp.28-34
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• 2016

A number of chiral selectors have been developed and applied for enantiomer separation of a variety of chiral compounds. Among these chiral selectors are chiral crown ethers, a class of synthetic host polyether molecules that bind protonated chiral primary amines with high selectivity and affinity. In this paper, two important chiral crown ethers as chiral selectors of bis-(1,1'-binaphthyl)-22-crown-6 and (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) are focused. They have been widely used to resolve the enantiomers of chiral compounds containing a primary amino moiety using chiral stationary phases (CSPs) or chiral selectors by high-performance liquid chromatography (HPLC), capillary electrophoresis (CE) and so on in chirotechnology. Also, it was described that the commercially available covalent type HPLC CSPs derived from (+)- and (-)-18-C-6-TA have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• Analytical Science and Technology
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• v.7 no.1
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• pp.41-52
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• 1994

The importance of separation comes from demands on study for exact effect of synthetic drugs and the reactivity of enantiomer in biological system. Racemization rate was measured under the influence of heat, acid, UV-light, enzyme(trypsin) and 6N-HCl at $105^{\circ}C$ on alanine, threonine, isoleucine, lecuine, aspartic acid, methionine, glutamic acid, tyrosine. The method for the identification of overlapped amino acids with GC was developed from the close study of fragmentation pattern with mass spectrometry. With cyclodextrin bonded phase by HPLC, the separation of dansyl amino acid was tested for compartison.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2493-2496
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• 2011

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.214.3-214.3
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• 2003

The chiral separation of multiple ${\beta}$-blockers is described for their accurate chiral discrimination by chiral capillary electrophoresis (CE). The cyc1odextrin-modified CE system was operated in the reversed polarity mode. In this mode, fairly good enantiomeric resolutions were achieved. Relative migration times to internal standard under optimum conditions were characteristic of each enantiomer with good precision. Therefore, in this study, the usefulness for the chiral separation and accurate identification will be discussed.