Elution order in liquid chromatography on cyclodextrin phases. Dependence on the amount of organic modifier in the eluent

Andersson, Jan T.; Kaiser, Günter

doi:10.1007/bf00491310

Cited by 2 publications

(1 citation statement)

References 2 publications

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“…Phenomena of chiral recognition reversal in HPLC have been observed in polysaccharide chiral stationary phases (CSPs) , cyclodextrin CSPs , macrocyclic antibiotic CSPs , brush/Pirkle‐type CSPs , and crown ether CSPs , etc. Protein‐based CSPs exhibit good enantioselectivity for various chiral compounds , due to multiple‐binding sites on the surface.…”

Section: Introductionmentioning

confidence: 99%

Reversal of elution order of N‐(2,4‐dinitrophenyl)‐proline and N‐(2,4‐dinitrophenyl)‐serine in HPLC by BSA chiral stationary phase

Wang

Xiong

et al. 2013

J of Separation Science

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N-(2,4-dinitrophenyl)-proline and N-(2,4-dinitrophenyl)-serine were enantiomerically resolved on the BSA chiral stationary phase by HPLC in reversed-phase mode. Effects of chromatographic conditions on enantioseparation and elution order have been investigated in detail. For these two samples, reversal of enantiomer elution order was observed by changing buffer pH, the content of acetonitrile, or alcohol modifiers in mobile phase, which is firstly reported in the BSA chiral stationary phase studies. More interestingly, combined effect between buffer pH and the content of acetonitrile was also observed. In addition, coelution range of enantiomers varied along with the content of acetonitrile in mobile phase.

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Section: Introductionmentioning

confidence: 99%

Reversal of elution order of N‐(2,4‐dinitrophenyl)‐proline and N‐(2,4‐dinitrophenyl)‐serine in HPLC by BSA chiral stationary phase

Wang

Xiong

et al. 2013

J of Separation Science

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Thermodynamics and Kinetics of Chiral Separations with β‐Cyclodextrin Stationary Phase: I. Effect of Mobile Phase Composition

McGuffin

2007

Journal of Liquid Chromatography & Related Technologies

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A series of coumarin-based solutes, consisting of warfarin, coumachlor, coumafuryl, coumatetralyl, and 4-hydroxycoumarin, are utilized to elucidate the thermodynamic and kinetic aspects of chiral separations. These solutes are separated on a b-cyclodextrin stationary phase with a polar-organic mobile phase. Preliminary results demonstrate that the equilibration time is extremely long when the mobile phase consists of acetonitrile, methanol, or mixtures thereof. However, the equilibration time is substantially reduced when acetic acid or triethylamine modifiers are added. Linear isotherms are obtained when acid modifier is present, but nonlinear isotherms are obtained when no modifier or only amine modifier is present. The concentration of each component of the mobile phase is varied individually to observe the effects on the thermodynamic and kinetic behavior, including the retention factor, chiral selectivity, and kinetic mass transfer rate. In general, an increase in methanol or triethylamine concentration decreases retention, but an increase in acetic acid concentration slightly increases retention. However, it is noteworthy that triethylamine enhances chiral selectivity, whereas acetic acid diminishes it. Acetic acid has the opposite effect when amine is not present, indicating that the acid and amine interact with each other. With regard to the kinetic behavior, the mass transfer rate constant of the coumarin solutes generally decreases as the retention factor increases. However, the second enantiomer often has a surprisingly faster mass transfer rate than the first enantiomer, even though it is more retained. This difference indicates that different kinetic contributions arise at the chiral and achiral selective sites.

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Elution order in liquid chromatography on cyclodextrin phases. Dependence on the amount of organic modifier in the eluent

Cited by 2 publications

References 2 publications

Reversal of elution order of N‐(2,4‐dinitrophenyl)‐proline and N‐(2,4‐dinitrophenyl)‐serine in HPLC by BSA chiral stationary phase

Reversal of elution order of N‐(2,4‐dinitrophenyl)‐proline and N‐(2,4‐dinitrophenyl)‐serine in HPLC by BSA chiral stationary phase

Thermodynamics and Kinetics of Chiral Separations with β‐Cyclodextrin Stationary Phase: I. Effect of Mobile Phase Composition

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