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Kopchenova MV, Stepanova MV, Asnin LD. Unusual Difference in Enantioselectivity of Two Chiral Stationary Phases with Grafted Antibiotic Ristocetin A. Chromatographia 2021. [DOI: 10.1007/s10337-021-04006-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2
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Klimova YA, Asnin LD. Enantioselective adsorption dynamics of leucyl-leucine in a Chirobiotic R column. J Chromatogr A 2020; 1635:461771. [PMID: 33302135 DOI: 10.1016/j.chroma.2020.461771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 12/15/2022]
Abstract
The dynamics of adsorption of the Leu-Leu stereoisomers in a chromatographic column packed with the Chirobiotic R chiral stationary phase bearing grafted antibiotic ristocetin A was studied by means of measurement and analysis of van Deemter plots. Similar measurements were carried out with weakly retained Gly-Gly for the sake of comparison. The bulk diffusion coefficients of the investigated dipeptides were also determined. It is found that the van Deemter plots of both the Leu-Leu stereoisomers and Gly-Gly have an uncommon convex-upward shape. Besides, the van Deemter B coefficients for the Leu-Leu stereoisomers, but not for Gly-Gly, have unusually high values. It is suggested that a high transcolumn contribution to eddy dispersion, which turned out to be enantioselective, accounts for these findings. Adsorption kinetics of all the dipeptides considered is relatively slow, the adsorption rate constant (kads) being of order of magnitude 20-60 s-1. kads does not depend on the configuration of Leu-Leu stereoisomers, although their affinity toward the chiral selector depends on this factor. This supports the above hypothesis that eddy dispersion is mainly responsible for the observed peculiarities in the dynamic behavior of dipeptides, and adsorption kinetics has secondary importance in this phenomenon.
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Affiliation(s)
- Yana A Klimova
- Perm National Research Polytechnic University, 29 Komsomolsky Al., Perm 614990, Russian Federation
| | - Leonid D Asnin
- Perm National Research Polytechnic University, 29 Komsomolsky Al., Perm 614990, Russian Federation.
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3
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Islam MF, Adhikari S, Paik M, Lee W. Determination of Chemical and Enantiomeric Purity of α‐Amino Acids and their Methyl Esters as N‐Fluorenylmethoxycarbonyl Derivatives Using Amylose‐derived Chiral Stationary Phases. B KOREAN CHEM SOC 2019. [DOI: 10.1002/bkcs.11694] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - Suraj Adhikari
- College of PharmacyChosun University Gwangju 501‐759 South Korea
| | - Man‐Jeong Paik
- College of PharmacySunchon National University Suncheon 540‐950 South Korea
| | - Wonjae Lee
- College of PharmacyChosun University Gwangju 501‐759 South Korea
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4
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Heart-cut achiral-chiral LC-LC method development using factorial design: application to the chiral separation of ketoprofen. Anal Bioanal Chem 2016; 409:1135-1144. [DOI: 10.1007/s00216-016-0039-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 09/28/2016] [Accepted: 10/18/2016] [Indexed: 10/20/2022]
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5
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Bocian S, Skoczylas M, Buszewski B. Amino acids, peptides, and proteins as chemically bonded stationary phases - A review. J Sep Sci 2015; 39:83-92. [DOI: 10.1002/jssc.201500825] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/20/2015] [Accepted: 09/20/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Szymon Bocian
- Chair of Environmental Chemistry & Bioanalytics, Faculty of Chemistry; Nicolaus Copernicus University; Torun Poland
| | - Magdalena Skoczylas
- Chair of Environmental Chemistry & Bioanalytics, Faculty of Chemistry; Nicolaus Copernicus University; Torun Poland
| | - Bogusław Buszewski
- Chair of Environmental Chemistry & Bioanalytics, Faculty of Chemistry; Nicolaus Copernicus University; Torun Poland
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6
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Wu H, Song G, Wang D, Yu H, Ke Y, Liang X. Study of stereomeric peptoid chiral stationary phases containing different chiral side chains. J Chromatogr A 2013; 1298:152-6. [DOI: 10.1016/j.chroma.2013.05.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/15/2013] [Accepted: 05/15/2013] [Indexed: 10/26/2022]
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7
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Ilisz I, Aranyi A, Pataj Z, Péter A. Enantiomeric separation of nonproteinogenic amino acids by high-performance liquid chromatography. J Chromatogr A 2012; 1269:94-121. [DOI: 10.1016/j.chroma.2012.07.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 07/02/2012] [Accepted: 07/06/2012] [Indexed: 10/28/2022]
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8
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Wu H, Su X, Li K, Yu H, Ke Y, Liang X. Improvement of peptoid chiral stationary phases by modifying the terminal group of selector. J Chromatogr A 2012; 1265:181-5. [DOI: 10.1016/j.chroma.2012.09.081] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 09/20/2012] [Accepted: 09/24/2012] [Indexed: 10/27/2022]
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9
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Comparison of the sensitivity of evaporative universal detectors and LC/MS in the HILIC and the reversed-phase HPLC modes. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:4133-9. [DOI: 10.1016/j.jchromb.2009.10.027] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Revised: 10/21/2009] [Accepted: 10/25/2009] [Indexed: 11/23/2022]
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10
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Honetschlägerová-Vadinská M, Srkalová S, Bosáková Z, Coufal P, Tesarová E. Comparison of enantioselective HPLC separation of structurally diverse compounds on chiral stationary phases with different teicoplanin coverage and distinct linkage chemistry. J Sep Sci 2009; 32:1704-11. [DOI: 10.1002/jssc.200800725] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Ilisz I, Berkecz R, Péter A. Retention mechanism of high-performance liquid chromatographic enantioseparation on macrocyclic glycopeptide-based chiral stationary phases. J Chromatogr A 2008; 1216:1845-60. [PMID: 18762302 DOI: 10.1016/j.chroma.2008.08.041] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 08/11/2008] [Accepted: 08/13/2008] [Indexed: 10/21/2022]
Abstract
The development of methods for the separation of enantiomers has attracted great interest in the past 20 years, since it became evident that the potential biological or pharmacological applications are mostly restricted to one of the enantiomers. In the past decade, macrocyclic antibiotics have proved to be an exceptionally useful class of chiral selectors for the separation of enantiomers of biological and pharmacological importance by means of high-performance liquid chromatography (HPLC), thin-layer chromatography and electrophoresis. The glycopeptides avoparcin, teicoplanin, ristocetin A and vancomycin have been extensively used as chiral selectors in the form of chiral bonded phases in HPLC, and HPLC stationary phases based on these glycopeptides have been commercialized. In fact, the macrocyclic glycopeptides are to some extent complementary to one another: where partial enantioresolution is obtained with one glycopeptide, there is a high probability that baseline or better separation can be obtained with another. This review sets out to characterize the physicochemical properties of these macrocyclic glycopeptide antibiotics and, through their application, endeavors to demonstrate the mechanism of separation on macrocyclic glycopeptides. The sequence of elution of the stereoisomers and the relation to the absolute configuration are also discussed.
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Affiliation(s)
- István Ilisz
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary
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12
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Wang C, Jiang C, Armstrong DW. Considerations on HILIC and polar organic solvent-based separations: use of cyclodextrin and macrocyclic glycopetide stationary phases. J Sep Sci 2008; 31:1980-90. [PMID: 18615818 PMCID: PMC4301416 DOI: 10.1002/jssc.200800174] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
There is a natural tendency in science to prefer straightforward, logical classification systems. The use of mobile phase-stationary phase combinations that do not fit neatly into the standard "normal phase" or "reversed-phase" categories has been going on for over 50 years. The term "hydrophilic interaction chromatography" (HILIC) is sometimes being used as a general category for these "other" separations. In some cases, it may be appropriate and in others, not. Indeed the mechanistic constrains used to define the method seem to be varying with time. Given the name HILIC, it is assumed that water is not only present in the mobile phase, but also plays an essential role in the retention mechanism. However, there is residual water present in all organic solvents. Regardless, the number of reported separations in this alternative mode has increased tremendously in the last two decades. This is due to the advent of new stationary phases and an emphasis on polar, biologically important molecules. We discuss the relationships between HILIC and other chromatographic modes. We then examine two classes of stationary phases that have played a major role in these separations. These particular stationary phases can be used to provide appreciable mechanistic information as well.
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Affiliation(s)
- Chunlei Wang
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019
| | - Chunxia Jiang
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019
| | - Daniel W Armstrong
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019
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13
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Ilisz I, Berkecz R, Péter A. HPLC separation of amino acid enantiomers and small peptides on macrocyclic antibiotic-based chiral stationary phases: a review. J Sep Sci 2007; 29:1305-21. [PMID: 16894775 DOI: 10.1002/jssc.200600046] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The search for new and effective chiral selectors capable of separating a wide variety of enantiomeric compounds is an ongoing process. In the past decade, macrocyclic antibiotics have proved to be an exceptionally useful class of chiral selectors for the separation of enantiomers of biological and pharmacological importance by means of HPLC, TLC and electrophoresis. More chiral analytes have been resolved through the use of glycopeptides than with all the other macrocyclic antibiotics combined (ansamycins, thiostrepton, aminoglycosides, etc.). The glycopeptides avoparcin, teicoplanin, ristocetin A and vancomycin have been extensively used as chiral selectors in the form of chiral bonded phases in HPLC, and HPLC stationary phases based on these glycopeptides have been commercialized. Teicoplanin, vancomycin, their analogs and ristocetin A seem to be the most useful glycopeptide HPLC bonded phases for the enantioseparation of proteins and unusal native and derivatized amino acids. In fact, the macrocyclic glycopeptides are to some extent complementary to one another: where partial enantioresolution is obtained with one glycopeptide, there is a high probability that baseline or better separation can be obtained with another. This review sets out to characterize the physicochemical properties of these antibiotics and their application in the enantioseparations of amino acids. The mechanism of separation, the sequence of elution of the stereoisomers and the relation to the absolute configuration are also discussed.
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Affiliation(s)
- István Ilisz
- Department of Inorganic and Analytical Chemistry, University of Szeged, Hungary
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14
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Liu Y, Lantz AW, Armstrong DW. High Efficiency Liquid and Super‐/Subcritical Fluid‐Based Enantiomeric Separations: An Overview. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120030600] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Ying Liu
- a Department of Chemistry , Iowa State University , Ames , Iowa , 50011‐3111 , USA
| | - Andrew W. Lantz
- a Department of Chemistry , Iowa State University , Ames , Iowa , 50011‐3111 , USA
| | - Daniel W. Armstrong
- a Department of Chemistry , Iowa State University , Ames , Iowa , 50011‐3111 , USA
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15
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Bechtold M, Felinger A, Held M, Panke S. Adsorption behavior of a teicoplanin aglycone bonded stationary phase under harsh overload conditions. J Chromatogr A 2007; 1154:277-86. [PMID: 17449046 DOI: 10.1016/j.chroma.2007.03.103] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Revised: 03/27/2007] [Accepted: 03/28/2007] [Indexed: 11/17/2022]
Abstract
Silica-bonded teicoplanin aglycone allows enantioseparation of amino acids by reversed-phase liquid chromatography with a low organic solvent content. However, a reversible change in the adsorption behavior leading to a retention time shift (RTS) was observed when a preparative scale column was treated with harsh preparative chromatography-like conditions between finite-injection HPLC runs conducted under exactly the same conditions. This behavior was observed for all five investigated aliphatic and aromatic amino acids. In all cases, the retention times were prolonged after the overload conditions and the RTS was more pronounced for the later eluting d-enantiomer. We defined a standardized method for measuring the RTS and performed a systematic investigation on the influence of experimental conditions (type and concentration of pH modifier and organic modifier, temperature, pH) on the RTS. In this way a solvent composition--90/10 50 mM NH4Ac pH 5.8/MeOH--was identified that yielded no observable shift in retention time after overload conditions for both enantiomers. In order to treat the observed phenomenon on a mechanistic level, we applied band profile analysis based on the stochastic theory of chromatography and identified two different enantioselective sites. When the band profile analysis was performed on elution profiles obtained from runs with prolonged retention time after harsh overload conditions, the retention time shift could be attributed to both differentiable types of adsorption sites. One site was found to make both, enantioselective and non-selective contributions.
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Affiliation(s)
- Matthias Bechtold
- Bioprocess Laboratory, Institute of Process Engineering, ETH Zurich, Switzerland
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16
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Xiao TL, Zhang B, Lee JT, Hui F, Armstrong DW. REVERSAL OF ENANTIOMERIC ELUTION ORDER ON MACROCYCLIC GLYCOPEPTIDE CHIRAL STATIONARY PHASES. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-100106094] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- T. L. Xiao
- a Department of Chemistry , Iowa State University , Ames, IA, 50011, U.S.A
| | - B. Zhang
- a Department of Chemistry , Iowa State University , Ames, IA, 50011, U.S.A
| | - J. T. Lee
- b Advanced Separation Technologies, Inc. , Whippany, NJ, 07981, U.S.A
| | - F. Hui
- c Laboratoire Environment et Chimie Analytique , CNRS ERS657, ESPCI, Paris, 75005, France
| | - D. W. Armstrong
- d Department of Chemistry , Iowa State University , Ames, IA, 50011, U.S.A
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17
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Kuznetsov MA, Nesterenko PN, Vasiyarov GG, Staroverov SM. Sorbents with immobilized glycopeptide antibiotics for separating optical isomers by high-performance liquid chromatography. APPL BIOCHEM MICRO+ 2006. [DOI: 10.1134/s0003683806060020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Boesten JMM, Berkheij M, Schoemaker HE, Hiemstra H, Duchateau ALL. Enantioselective high-performance liquid chromatographic separation of N-methyloxycarbonyl unsaturated amino acids on macrocyclic glycopeptide stationary phases. J Chromatogr A 2006; 1108:26-30. [PMID: 16443231 DOI: 10.1016/j.chroma.2005.12.088] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Revised: 12/19/2005] [Accepted: 12/20/2005] [Indexed: 10/25/2022]
Abstract
This paper describes the enantiomeric resolution of a series of unsaturated N-methyloxycarbonyl-alpha-H-alpha-amino acids (N-MOC-alpha-amino acids) on macrocyclic glycopeptide stationary phases by means of high-performance liquid chromatography (HPLC). Three types of glycopeptide phases, i.e. Chirobiotic T, V and R, were evaluated in both reversed-phase (RP) and polar ionic mode (PIM). The best results in terms of enantioselectivity and resolution were obtained on Chirobiotic R phase, with the PIM mobile phase giving the highest resolution per min. Investigation of the pH of the reversed-phase mobile phase in the pH range 4.1-5.9 showed little effect on enantioselectivity. The method was applied for monitoring the conversion and product enantiomeric excess of an enzymatic hydrolysis reaction using N-MOC-alpha-H-alpha-amino acid esters as substrate.
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Affiliation(s)
- J M M Boesten
- DSM Pharma Chemicals, Department of Advanced Synthesis, Catalysis and Development, P.O. Box 18, 6160 MD Geleen, The Netherlands
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19
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Huang J, Chen H, Zhang P, Li T. Improvement of proline enantioselective stationary phases by replacing the 9-fluorenylmethoxycarbonyl group. J Chromatogr A 2006; 1109:307-11. [PMID: 16483587 DOI: 10.1016/j.chroma.2006.01.072] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Revised: 01/14/2006] [Accepted: 01/17/2006] [Indexed: 10/25/2022]
Abstract
The role of 9-fluorenylmethoxycarbonyl (Fmoc) in previously reported proline enantioselective stationary phases was investigated. Seven stationary phases in which the Fmoc group was replaced by other groups were prepared and evaluated in normal phase mode. The Fmoc group proved nonessential for the broad enantioselectivity observed, as the stationary phase with a trimethylacetyl (Tma) group proved much more effective than the one with the Fmoc group. For the 53 analytes studied, the stationary phase with the Tma group resolved 39, while the one with the Fmoc group resolved 19. Separation factors achieved for the stationary phase with the Tma group are also significantly higher than those for the stationary phase with the Fmoc group. The stationary phase with the (-)-2-(2,4,5,7-tetranitro-9-fluorenylideneaminooxy)propionyl (Tapa) group provides very different selectivity profile when compared to the one with the Tma group. In most of the proline stationary phases studied, pi-pi interaction is not the dominant interaction for the enantioselective recognition.
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Affiliation(s)
- Junmin Huang
- Department of Chemistry, Box 9573, Mississippi State University, Mississippi State, MS 39762, USA
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Bosáková Z, Curínová E, Tesarová E. Comparison of vancomycin-based stationary phases with different chiral selector coverage for enantioselective separation of selected drugs in high-performance liquid chromatography. J Chromatogr A 2005; 1088:94-103. [PMID: 16130736 DOI: 10.1016/j.chroma.2005.01.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two vancomycin-based chiral stationary phases (CSPs) with different coverage of the chiral selector vancomycin (Chirobiotic V and Chirobiotic V2) were compared. beta-Blockers and profens, as structurally diverse groups of drugs, were chosen as analytes. Retention and enantioseparation of beta-blockers were studied in reversed-phase (RP) and polar-organic (PO) separation modes. Higher retention and better enantioresolution were obtained on the CSP with higher coverage of vancomycin in the both separation modes. Baseline separation of four beta-blockers (eight enantiomers) in the PO mode was achieved on the Chirobiotic V2 column within 15 min. The enantioseparation of profens did not bring so excellent and easy to interpret results. Higher retention of profens on the Chirobiotic V2 column was not always accompanied by an improvement of their chiral separation in the RP mode. The polar-organic mode was not suitable for these derivatives at all. The most interesting result was obtained with flobufen; its chiral center is further away from the rigid part of the molecule, which mostly causes difficulties in enantioselective recognition. Nevertheless, the enantiomers of flobufen were shown to be much better (baseline) resolved on the CSP with lower coverage of the chiral selector (Chirobiotic V).
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Affiliation(s)
- Z Bosáková
- Department of Analytical Chemistry, Faculty of Science, Charles University, Albertov 2030, 128 40 Prague 2, Czech Republic
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Sharp VS, Letts MN, Risley DS, Rose JP. Enantiomeric separation of dansyl amino acids using macrocyclic antibiotics as chiral mobile phase additives by narrow-bore high-performance liquid chromatography. Chirality 2004; 16:153-61. [PMID: 14770411 DOI: 10.1002/chir.20002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Seven macrocyclic antibiotics were evaluated as chiral selectors for the enantiomeric separation of 11 dansyl amino acids using narrow-bore high-performance liquid chromatography (HPLC). The macrocyclic antibiotics were incorporated as mobile phase additives to determine the enantioselective effects on the chiral analytes. The resolution and capacity factor (k') of each analyte were assessed while varying the structure of macrocyclic antibiotic and the mobile phase buffer pH. The selectivity of the chiral selectors was measured as a function of changes in these parameters. All 11 dansyl amino acids were separated by at least one of the chiral selectors. Three-dimensional computer modeling of the more effective chiral selectors illustrated the importance of macrocyclic antibiotic structure concerning stereospecific analyte interaction.
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Affiliation(s)
- V Scott Sharp
- Lilly Research Laboratories, Lilly Corporate Center, Bldg. 77, Drop 0734, Indianapolis, IN 46285, USA.
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Péter A, Vékes E, Armstrong DW. Effects of temperature on retention of chiral compounds on a ristocetin A chiral stationary phase. J Chromatogr A 2002; 958:89-107. [PMID: 12134834 DOI: 10.1016/s0021-9673(02)00390-4] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The isocratic retention of enantiomers of chiral analytes, i.e. tryptophan, 1,2,3,4-tetrahydroisoquinoline and gamma-butyrolac tone analogs, was studied on a ristocetin A chiral stationary phase at different temperatures and with different mobile phase compositions, using the reversed-phase, polar-organic and normal-phase modes. By variation of the both mobile phase composition and the temperature, baseline separations could be achieved for these enantiomers. The retention factors and selectivity factors for the enantiomers of all investigated compounds decreased with increasing temperature. The natural logarithms of the retention factors (ln k) of the investigated compounds depended linearly on the inverse of temperature (1/T). van't Hoff plots afforded thermodynamic parameters, such as the apparent change in enthalpy (deltaH(o)), the apparent change in entropy (deltaS(o)) and the apparent change in Gibbs free energy (deltaG(o) ) for the transfer of analyte from the mobile to the stationary phase. The thermodynamic parameters (deltaH(o), deltaS(o) and deltaG(o)) were calculated in order to promote an understanding of the thermodynamic driving forces for retention in this chromatographic system.
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Affiliation(s)
- Antal Péter
- Department of Inorganic and Analytical Chemistry, University of Szeged, Hungary.
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Abstract
The macrocyclic antibiotics have recently gained popularity as chiral selectors in CE, HPLC and TLC. The macrocyclic antibiotics used for chiral separations include the ansamycins, the glycopeptides, and the polypeptide antibiotic thiostrepton. Although not strictly considered macrocyclic antibiotics, the aminoglycosides are antibiotics that have been used for chiral separations in CE. More chiral analytes have been resolved using the glycopeptides than with the other macrocyclic antibiotics combined. The glycopeptides vancomycin, ristocetin A and teicoplanin have been used extensively as chiral selectors in CE, with ristocetin A appearing to be the most useful chiral selector followed by vancomycin and teicoplanin, respectively. The macrocyclic antibiotics have also been used as chiral bonded phases in HPLC, and HPLC stationary phases based on vancomycin, ristocetin A and teicoplanin have been commercialized. Ristocetin A seems to be the most useful glycopeptide HPLC bonded phase, but its greater expense can be a drawback. The macrocyclic antibiotics have been used with micelles to improve efficiency, provide unique selectivity, and extend the range of separations to neutral solutes. Changing the macrocyclic antibiotic used in CE or HPLC can significantly alter the enantioselectivity of the separations. In fact, the glycopeptide antibiotics are complementary to one another, where if a partial enantioresolution is obtained with one glycopeptide, there is a high probability that a baseline or better separation can be obtained with another.
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Affiliation(s)
- T J Ward
- Department of Chemistry, Millsaps College, Jackson, MS 39210, USA.
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Péter A, Török G, Armstrong DW, Tóth G, Tourwé D. High-performance liquid chromatographic separation of enantiomers of synthetic amino acids on a ristocetin A chiral stationary phase. J Chromatogr A 2000; 904:1-15. [PMID: 11209895 DOI: 10.1016/s0021-9673(00)00917-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A macrocyclic glycopeptide, ristocetin A, was used as chiral stationary phase for the high-performance liquid chromatographic separation of enantiomers of 28 unnatural amino acids, such as analogues of phenylalanine, tyrosine and tryptophan, and analogues containing 1,2,3,4-tetrahydroisoquinoline, tetraline or 1,2,3,4-tetrahydro-2-carboline skeletons. Excellent resolutions were achieved for most of the investigated compounds by using reversed-phase or a new polar-organic mobile phase system. The conditions of separation were optimized by variation of the mobile phase composition, temperature and flow-rate.
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Affiliation(s)
- A Péter
- Department of Inorganic and Analytical Chemistry, University of Szeged, Hungary.
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Tesarová E, Bosáková Z, Zusková I. Enantioseparation of selected N-tert.-butyloxycarbonyl amino acids in high-performance liquid chromatography and capillary electrophoresis with a teicoplanin chiral selector. J Chromatogr A 2000; 879:147-56. [PMID: 10893031 DOI: 10.1016/s0021-9673(00)00382-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Enantioseparation of N-tert.-butyloxycarbonyl amino acids (N-t-Boc-Aas) with teicoplanin chiral selector was performed in two different separation systems: A teicoplanin-based chiral stationary phase (CSP-TE) was used in reversed-phase HPLC, and the same chiral selector (CS) was added into a background electrolyte (BGE) in HPCE. The enantioselective interaction with the same CSP/CS can be influenced by several factors, such as mobile phase/background electrolyte composition: the buffer concentration, pH, the CS concentration, the presence of organic modifiers. In addition, the charge of the chiral selector related to the charge of the analyte and to EOF are important variables in CE. The effect of these parameters on enantioselectivity and enantioseparation of selected N-t-Boc-Aas was studied. The presence of a sufficient concentration (1% solution) of a triethylamine acetate buffer in the mobile phase was shown to be essential for enantioseparation of these blocked amino acids in HPLC. A certain concentration of teicoplanin aggregates (along with teicoplanin molecules) in the BGE is required to obtain enantioseparation of N-t-Boc-Aas in HPCE.
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Affiliation(s)
- E Tesarová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague 2, Czech Republic.
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