Dependence of chiral separations on the amount of cyclodextrins as selectors, employing the partial filling technique in capillary zone electrophoresis

Ahmad, A.L.; Paulsen-Sörman, Ulla; Westerlund, Douglas

doi:10.1007/bf02490569

Cited by 13 publications

(10 citation statements)

References 11 publications

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“…So, in order to perform a quantitative trapping of one enantiomer, one should not introduce a zone length shorter than 3 mm. As the absolute amount of selector is related to the amount of sample injected [52], the concentration of the selector should be chosen according to the injected sample amount. To better appreciate the effect of main experimental parameters on enantioselectivity, a better understanding of separation mechanism was necessary and the knowledge of complexation constants and complex mobility is of prime importance.…”

Section: Infinite Enantiomeric Resolution With Ultrashort Pfmentioning

confidence: 99%

Ultrashort partial‐filling technique in capillary electrophoresis for infinite resolution of tramadol enantiomers and its metabolites with highly sulfated cyclodextrins

et al. 2004

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The possibility to enhance resolution to infinite value in chiral capillary electrophoresis is attained as soon as the apparent mobility of one enantiomer becomes opposite to the other. This could be achieved on the basis of the carrier ability of multiple charged chiral selectors such as highly sulfated cyclodextrin (HS-CD). With tramadol and its phase I metabolites selected as model compounds, the HS-gamma-CD was found to be the most appropriate chiral selector. The CD concentration was determined where one enantiomer still migrated as a cation while the other migrated in the opposite side. Besides the chiral selector concentration, secondary parameters such as buffer concentration appeared to be critical to reach infinite resolution. The latter was achieved with partial filling technique using ultrashort separation zones (a few mm). In order to better understand the interaction mechanism between the selected CD and the analytes, the classical affinity capillary electrophoresis method, although not fully satisfactory because of ionic strength variations within a series of mobility shift measurements, was applied to estimate complexation constants and complex mobilities. The results obtained point to the prevailing role of complex mobility differences in the enantioselectivity mechanism.

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Section: Infinite Enantiomeric Resolution With Ultrashort Pfmentioning

confidence: 99%

Ultrashort partial‐filling technique in capillary electrophoresis for infinite resolution of tramadol enantiomers and its metabolites with highly sulfated cyclodextrins

et al. 2004

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“…The most recent applications of the PFT in chiral CE include, the use of tert-butylcarbamoylquinine [199], avidin analogues [203], 18C 6 H 4 [130], quail egg yolk riboflavin binding protein [201] and methyl-b-CD [69,82] as chiral selectors. Tert.-butylcarbamoylquinine dissolved in a nonaqueous BGE solution (ethanol-methanol, octanic acid and triethylamine) was used for enantiomeric separation of N-derivatized amino acids [199].…”

Section: Interference With Uv Detectionmentioning

confidence: 99%

“…Separations of the enantiomers were optimized by adjusting the concentration and the plug length of the protein solution within the capillary. The PFT provides the possibility to regulate enantioseparation by concentration and amount or plug length of the chiral selector [69].…”

Section: Interference With Uv Detectionmentioning

confidence: 99%

Recent developments in chiral capillary electrophoresis and applications of this technique to pharmaceutical and biomedical analysis

Ahmad

2001

Electrophoresis

189

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This paper provides an overview of the current status of chiral capillary electrophoresis (CE). The emphasis is placed on the application of CE in chiral separation of various racemic compounds. During the last two years about 280 papers, several review articles, and two entire issues, edited by S. Fanali (Electrophoresis 1999, 20, 2577-2798, and H. Nishi and S. Terabe (J. Chromatogr. A 2000, 879, 1-471.) have been devoted to chiral CE. Enantiomeric separations of various compounds, e.g., pharmaceuticals, drug candidates, drugs and related metabolites in biological fluids, amino acids, di- and tri peptides, pesticides and fungicides, have been performed using different chiral selectors. Native and derivatized cyclodextrins continue to be the most widely used chiral selectors. Other chiral selectors such as natural and synthetic chiral micelles, crown ethers, chiral ligands, proteins, oligo- and polysaccharides, and macrocyclic antibiotics have also been applied to chiral CE separations.

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“…Previous studies using the partial filling technique have mainly focused on adjusting the plug length of the protein to achieve efficient separations of enantiomers [5,19,26,27]. The plug lengths used in these studies have been rather short compared to the effective capillary length.…”

Section: Concentration Of Cel7amentioning

confidence: 99%

A statistical experimental design to study factors affecting enantioseparation of propranolol by capillary electrophoresis with cellobiohydrolase (Cel7A) as chiral selector

et al. 2002

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The capillary electrophoretic enantioseparation of rac-propranolol using cellobiohydrolase Tr Cel7A as selector was optimized by an unbiased statistical experimental design. A set of pre-experiments was performed in order to identify critical experimental factors. In the definitive chemometric design pH, ranging from 5 to 7, ionic strength ranging between 0.01 and 0.02 and organic solvent additive in concentration from 1 to 19% v/v were studied. The response surface plot revealed a separation optimum in the pH interval studied. When all parameters were taken into account, a background electrolyte consisting of 0.016 M bistris-acetate buffer with pH 6.5 and 17% v/v acetonitrile gave the optimum separation. The significance of the statistical design was confirmed by the generally good agreement obtained between predicted response and actual experimental data.

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Dependence of chiral separations on the amount of cyclodextrins as selectors, employing the partial filling technique in capillary zone electrophoresis

Cited by 13 publications

References 11 publications

Ultrashort partial‐filling technique in capillary electrophoresis for infinite resolution of tramadol enantiomers and its metabolites with highly sulfated cyclodextrins

Ultrashort partial‐filling technique in capillary electrophoresis for infinite resolution of tramadol enantiomers and its metabolites with highly sulfated cyclodextrins

Recent developments in chiral capillary electrophoresis and applications of this technique to pharmaceutical and biomedical analysis

A statistical experimental design to study factors affecting enantioseparation of propranolol by capillary electrophoresis with cellobiohydrolase (Cel7A) as chiral selector

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