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Szabó ZI, Boda F, Fiser B, Dobó M, Szőcs L, Tóth G. Chiral Separation of Oxazolidinone Analogs by Capillary Electrophoresis Using Anionic Cyclodextrins as Chiral Selectors: Emphasis on Enantiomer Migration Order. Molecules 2023; 28:molecules28114530. [PMID: 37299005 DOI: 10.3390/molecules28114530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/28/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023] Open
Abstract
Comparative chiral separations of enantiomeric pairs of four oxazolidinone and two related thio-derivatives were performed by capillary electrophoresis, using cyclodextrins (CDs) as chiral selectors. Since the selected analytes are neutral, the enantiodiscrimination capabilities of nine anionic CD derivatives were determined, in 50 mM phosphate buffer pH = 6. Unanimously, the most successful chiral selector was the single isomeric heptakis-(6-sulfo)-β-cyclodextrin (HS-β-CD), which resulted in the highest enantioresolution values out of the CDs applied for five of the six enantiomeric pairs. The enantiomer migration order (EMO) was the same for two enantiomeric pairs, irrespective of the CD applied. However, several examples of EMO reversals were obtained in the other cases. Interestingly, changing from randomly substituted, multi-component mixtures of sulfated-β-CD to the single isomeric chiral selector, enantiomer migration order reversal occurred for two enantiomeric pairs and similar observations were made when comparing heptakis-(2,3-di-O-methyl-6-O-sulfo)-β-CD, (HDMS-β-CD) with HS-β-CD. In several cases, cavity-size-dependent, and substituent-dependent EMO reversals were also observed. Minute differences in the structure of the analytes were also responsible for several cases of EMO reversal. The present study offers a complex overview of the chiral separation of structurally related oxazolidinones, and thio-analogs, highlighting the importance of the adequate choice of chiral selector in this group of compounds, where enantiomeric purity is of utmost importance.
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Affiliation(s)
- Zoltán-István Szabó
- Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, Gh. Marinescu 38, 540139 Târgu Mureș, Romania
- Sz-imfidum Ltd., Lunga nr. 504, 525401 Covasna, Romania
| | - Francisc Boda
- Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, Gh. Marinescu 38, 540139 Târgu Mureș, Romania
| | - Béla Fiser
- Higher Education and Industrial Cooperation Centre, University of Miskolc, Egyetemváros, H-3515 Miskolc, Hungary
- Ferenc Rákóczi II. Transcarpathian Hungarian Institute, 90200 Beregszász, Transcarpathia, Ukraine
- Department of Physical Chemistry, Faculty of Chemistry, University of Lodz, 90-149 Łódź, Poland
| | - Máté Dobó
- Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes E. 9, H-1085 Budapest, Hungary
| | - Levente Szőcs
- Cyclolab Ltd., Illatos út 7, H-1097 Budapest, Hungary
| | - Gergő Tóth
- Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes E. 9, H-1085 Budapest, Hungary
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2
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Cyclodextrins as chiral selectors in capillary electrophoresis: Recent trends in mechanistic studies. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2023.116987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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3
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Peluso P, Chankvetadze B. Recognition in the Domain of Molecular Chirality: From Noncovalent Interactions to Separation of Enantiomers. Chem Rev 2022; 122:13235-13400. [PMID: 35917234 DOI: 10.1021/acs.chemrev.1c00846] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
It is not a coincidence that both chirality and noncovalent interactions are ubiquitous in nature and synthetic molecular systems. Noncovalent interactivity between chiral molecules underlies enantioselective recognition as a fundamental phenomenon regulating life and human activities. Thus, noncovalent interactions represent the narrative thread of a fascinating story which goes across several disciplines of medical, chemical, physical, biological, and other natural sciences. This review has been conceived with the awareness that a modern attitude toward molecular chirality and its consequences needs to be founded on multidisciplinary approaches to disclose the molecular basis of essential enantioselective phenomena in the domain of chemical, physical, and life sciences. With the primary aim of discussing this topic in an integrated way, a comprehensive pool of rational and systematic multidisciplinary information is provided, which concerns the fundamentals of chirality, a description of noncovalent interactions, and their implications in enantioselective processes occurring in different contexts. A specific focus is devoted to enantioselection in chromatography and electromigration techniques because of their unique feature as "multistep" processes. A second motivation for writing this review is to make a clear statement about the state of the art, the tools we have at our disposal, and what is still missing to fully understand the mechanisms underlying enantioselective recognition.
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Affiliation(s)
- Paola Peluso
- Istituto di Chimica Biomolecolare ICB, CNR, Sede secondaria di Sassari, Traversa La Crucca 3, Regione Baldinca, Li Punti, I-07100 Sassari, Italy
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Avenue 3, 0179 Tbilisi, Georgia
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Peluso P, Chankvetadze B. Native and substituted cyclodextrins as chiral selectors for capillary electrophoresis enantioseparations: Structures, features, application, and molecular modeling. Electrophoresis 2021; 42:1676-1708. [PMID: 33956995 DOI: 10.1002/elps.202100053] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 02/06/2023]
Abstract
CDs are cyclic oligosaccharides consisting of α-d-glucopyranosyl units linked through 1,4-linkages, which are obtained from enzymatic degradation of starch. The coexistence of hydrophilic and hydrophobic regions in the same structure makes these macrocycles extremely versatile as complexing host with application in food, cosmetics, environmental, agriculture, textile, pharmaceutical, and chemical industries. Due to their inherent chirality, CDs have been also successfully used as chiral selectors in enantioseparation science, in particular, for CE enantioseparations. In the last decades, multidisciplinary approaches based on CE, NMR spectroscopy, X-ray crystallography, microcalorimetry, and molecular modeling have shed light on some aspects of recognition mechanisms underlying enantiodiscrimination. With the ever growing improvement of computer facilities, hardware and software, computational techniques have become a useful tool to model at molecular level the dynamics of diastereomeric associate formation to sample low-energy conformations, the binding energies between the enantiomer and the CD, and to profile noncovalent interactions contributing to the stability of CD/enantiomer association. On this basis, the aim of this review is to provide the reader with a critical overview on the applications of CDs in CE. In particular, the contemporary theory of the electrophoretic technique and the main structural features of CDs are described, with a specific focus on techniques, methods, and approaches to model CE enantioseparations promoted by native and substituted CDs. A systematic compilation of all published literature has not been attempted.
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Affiliation(s)
- Paola Peluso
- Istituto di Chimica Biomolecolare ICB, CNR, Sede secondaria di Sassari, Traversa La Crucca 3, Li Punti, Sassari, Italy
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Tbilisi, Georgia
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Gogolashvili A, Lomsadze K, Chankvetadze L, Takaishvili N, Peluso P, Dallocchio R, Salgado A, Chankvetadze B. Separation of tetrahydrozoline enantiomers in capillary electrophoresis with cyclodextrin-type chiral selectors and investigation of chiral recognition mechanisms. J Chromatogr A 2021; 1643:462084. [PMID: 33789195 DOI: 10.1016/j.chroma.2021.462084] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/16/2021] [Accepted: 03/19/2021] [Indexed: 12/13/2022]
Abstract
The recognition power and affinity pattern of various cyclodextrins (CD) towards the enantiomers of tetrahydrozoline (THZ) were studied using capillary electrophoresis (CE). As expected, affinity of THZ enantiomers and selectivity of recognition towards CD derivatives was strongly dependent on the cavity size and substituent type and pattern on the CD rims. Not only were the affinity strength and selectivity of recognition affected by the size of the cavity and chemistry of the CDs but also the affinity pattern. Another interesting example of opposite affinity pattern of enantiomers towards α- and β-CD was observed here. In addition, opposite affinity pattern of THZ enantiomers was seen towards β-CD and its acetylated derivatives, while methylation of β-CD did not affect the affinity pattern of THZ enantiomers. In order to get more information about structural mechanisms of the multivariate dependences mentioned above, rotating frame Overhauser enhancement spectroscopy (ROESY) and computation techniques were used. Significant differences between the structure of THZ complexes with different CDs with both methods were encountered. Good correlations between experimentally determined and computed structure of complexes, as well as between computed complex stabilities and enantiomer migration order (EMO) in CE were observed.
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Affiliation(s)
- Ann Gogolashvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia
| | - Ketevan Lomsadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia; School of Science and Technology, The University of Georgia, 77a, M. Kostava Str., Tbilisi 0171, Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia
| | - Nino Takaishvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia
| | - Paola Peluso
- Istituto di Chimica Biomolecolare ICB-CNR, Sede secondary a di Sassari, Traversa La Crucca 3, Regione Baldinca, Sassari, Li Punti 07100, Italy
| | - Roberto Dallocchio
- Istituto di Chimica Biomolecolare ICB-CNR, Sede secondary a di Sassari, Traversa La Crucca 3, Regione Baldinca, Sassari, Li Punti 07100, Italy
| | - Antonio Salgado
- NMR Spectroscopy Centre (CERMN), CAI Químicas, Faculty of Pharmacy, University of Alcalá, Alcalá de Henares, Madrid E-28805, Spain
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia.
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Single isomer cyclodextrins as chiral selectors in capillary electrophoresis. J Chromatogr A 2020; 1627:461375. [PMID: 32823120 DOI: 10.1016/j.chroma.2020.461375] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/24/2020] [Accepted: 06/28/2020] [Indexed: 12/23/2022]
Abstract
Since decades, cyclodextrins are one of the most powerful selectors in chiral capillary electrophoresis for the enantioseparation of diverse organic compounds. This review concerns papers published over the last decade (from 2009 until nowadays), dealing with the capillary electrophoretic application of single isomer cyclodextrin derivatives in chiral separations. Following a brief overview of their synthetic approaches, the inventory of the neutral, negatively and positively charged (including both permanently ionic and pH-tunable ionizable substituents) and zwitterionic CD derivatives is presented, with insights to underlying structural aspects by NMR spectroscopy and molecular modeling. CE represents an ideal tool to study the weak, non-covalent supramolecular interactions. The published methods are reviewed in the light of enantioselectivity, enantiomer migration order and the fine-tuning of enantiodiscrimination by the substitution pattern of the single entity selector molecules, which is hardly possible for their randomly substituted counterparts. All the reviewed publications herein support that cyclodextrin-based chiral capillary electrophoresis seems to remain a popular choice in pharmaceutical and biomedical analysis.
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Gogolashvili A, Chankvetadze L, Takaishvili N, Salgado A, Chankvetadze B. Separation of terbutaline enantiomers in capillary electrophoresis with neutral cyclodextrin‐type chiral selectors and investigation of the structure of selector‐selectand complexes using nuclear magnetic resonance spectroscopy. Electrophoresis 2020; 41:1023-1030. [DOI: 10.1002/elps.202000010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Ann Gogolashvili
- School of Exact and Natural SciencesInstitute of Physical and Analytical ChemistryTbilisi State University Tbilisi Georgia
| | - Lali Chankvetadze
- School of Exact and Natural SciencesInstitute of Physical and Analytical ChemistryTbilisi State University Tbilisi Georgia
| | - Nino Takaishvili
- School of Exact and Natural SciencesInstitute of Physical and Analytical ChemistryTbilisi State University Tbilisi Georgia
| | - Antonio Salgado
- Centro de Espectroscopía de RMN (CERMN)Faculty of PharmacyUniversity of AlcaláUniversity Campus Madrid Spain
| | - Bezhan Chankvetadze
- School of Exact and Natural SciencesInstitute of Physical and Analytical ChemistryTbilisi State University Tbilisi Georgia
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8
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Hu S, Zhang M, Li F, Breadmore MC. β-Cyclodextrin-copper (II) complex as chiral selector in capillary electrophoresis for the enantioseparation of β-blockers. J Chromatogr A 2019; 1596:233-240. [DOI: 10.1016/j.chroma.2019.03.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 02/28/2019] [Accepted: 03/12/2019] [Indexed: 11/29/2022]
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9
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Chankvetadze B. Contemporary theory of enantioseparations in capillary electrophoresis. J Chromatogr A 2018; 1567:2-25. [PMID: 30025609 DOI: 10.1016/j.chroma.2018.07.041] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/05/2018] [Accepted: 07/12/2018] [Indexed: 11/17/2022]
Abstract
The first separation of enantiomers in capillary electrophoresis (CE) counts slightly longer than three decades. Fast development of the practice and theory of chiral CE occurred in the past 30 years and today one can consider this technology to have a solid and mature theoretical background. The goal of the present review is not only to summarize the history and contemporary theory of enantioseparations by using CE but also to present the authors personal view where shall we head to with this attractive technology not only from the viewpoint of separation of enantiomers but also for better understanding the mechanisms of non-covalent (enantioselective) interactions in chemistry, biology, medicine and related disciplines.
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Affiliation(s)
- Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 1, 0179 Tbilisi, Georgia.
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10
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Řezanková K, Kohoutová R, Kuchař M, Král V, Řezanka P. Enantioseparation of novel psychoactive chiral amines and their mixture by capillary electrophoresis using cyclodextrins as chiral selectors. CHEMICAL PAPERS 2018. [DOI: 10.1007/s11696-018-0535-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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11
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Capillary electrophoresis separation of phenethylamine enantiomers using amino acid based ionic liquids. J Pharm Biomed Anal 2017; 148:245-250. [PMID: 29059613 DOI: 10.1016/j.jpba.2017.10.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/10/2017] [Accepted: 10/12/2017] [Indexed: 01/08/2023]
Abstract
In recent years increasing interest was drawn towards ionic liquids in analytical separation science, such as capillary electrophoresis. Ionic liquids combining tetrabutylammonium cations with chiral amino acid based anions were prepared and investigated as capillary electrophoresis background electrolyte additives for the enantioseparation of ephedrine, pseudoephedrine, and methylephedrine isomers. For the optimization of buffer pH and ionic liquid concentration a design of experiments approach was performed. The best results for the separation of all enantiomers were achieved using 125mmol/L tetrabutylammonium l-argininate in a 75mmol/L phosphate buffer pH 1.5 containing 30mmol/L β-cyclodextrin.
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Li X, Yao X, Xiao Y, Wang Y. Enantioseparation of single layer native cyclodextrin chiral stationary phases: Effect of cyclodextrin orientation and a modeling study. Anal Chim Acta 2017; 990:174-184. [DOI: 10.1016/j.aca.2017.07.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 07/03/2017] [Accepted: 07/08/2017] [Indexed: 10/19/2022]
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13
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Guo X, Liu Q, Hu S, Guo W, Yang Z, Zhang Y. Thermodynamic models to elucidate the enantioseparation of drugs with two stereogenic centers by micellar electrokinetic chromatography. J Chromatogr A 2017; 1512:133-142. [DOI: 10.1016/j.chroma.2017.07.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/06/2017] [Accepted: 07/07/2017] [Indexed: 01/22/2023]
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Cecilio Fonseca M, Santos da Silva RC, Nascimento CS, Bastos Borges K. Computational contribution to the electrophoretic enantiomer separation mechanism and migration order using modified β-cyclodextrins. Electrophoresis 2017; 38:1860-1868. [PMID: 28387965 DOI: 10.1002/elps.201600468] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 03/22/2017] [Accepted: 03/25/2017] [Indexed: 11/07/2022]
Abstract
Capillary electrophoresis (CE) is an extremely effective technique in many kinds of separations, including separation of enantiomers. Some additional techniques may be necessary to determine the enantiomer migration order (EMO) and also the mechanism involved in chiral recognition. This paper reports the development and optimization of a CE method for enantioseparation of racemic mixture of both R- and S-stereoisomers of tramadol (TRM) with a computational contribution for the EMO determination and the responsible mechanisms for chiral distinction. Parameters such as composition and concentration of background electrolyte (BGE) and type and concentration of cyclodextrins (CD) were evaluated. For calculations, a sequential methodology was used, resorting to semiempirical Parametric Model 3 (PM3) followed by calculations accomplished using density functional theory. The best results were obtained with sulfated-β-CD (s-β-CD) and carboxymethyl-β-cyclodextrin (cm-β-CD) as chiral selector. Calculations show that the inclusion of TRM is not a probable process due to the shape of the TRM molecule and the size CDs cavities. Therefore, the chiral recognition process occurs by the formation of association complexes between modified β-CD and groups of TRM molecules. The structural analysis of the fragments of complexes at a pH of 10 and a thermodynamic analysis of the complexes' formation process allows determining the EMO. Comparing results obtained experimentally and computationally, it seems that the developed method is adequate for separation of TRM enantiomers and the computational methodology is also adequate to get a sense of the system at a molecular level.
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Affiliation(s)
- Matheus Cecilio Fonseca
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| | - Ricky Cássio Santos da Silva
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| | - Clebio Soares Nascimento
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| | - Keyller Bastos Borges
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
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Wahl J, Furuishi T, Yonemochi E, Meinel L, Holzgrabe U. Characterization of complexes between phenethylamine enantiomers and β-cyclodextrin derivatives by capillary electrophoresis-Determination of binding constants and complex mobilities. Electrophoresis 2017; 38:1188-1200. [DOI: 10.1002/elps.201600522] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/10/2017] [Accepted: 01/23/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Joachim Wahl
- University of Würzburg; Institute for Pharmacy and Food Chemistry; Würzburg Germany
| | - Takayuki Furuishi
- University of Würzburg; Institute for Pharmacy and Food Chemistry; Würzburg Germany
- Department of Physical Chemistry, Faculty of Pharmaceutical Sciences; Hoshi University; Tokyo Japan
| | - Etsuo Yonemochi
- Department of Physical Chemistry, Faculty of Pharmaceutical Sciences; Hoshi University; Tokyo Japan
| | - Lorenz Meinel
- University of Würzburg; Institute for Pharmacy and Food Chemistry; Würzburg Germany
| | - Ulrike Holzgrabe
- University of Würzburg; Institute for Pharmacy and Food Chemistry; Würzburg Germany
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Recent advances on the use of cyclodextrins in the chiral analysis of drugs by capillary electrophoresis. J Chromatogr A 2016; 1467:79-94. [DOI: 10.1016/j.chroma.2016.08.029] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 07/29/2016] [Accepted: 08/11/2016] [Indexed: 11/19/2022]
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17
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Advances in the Use of Cyclodextrins as Chiral Selectors in Capillary Electrokinetic Chromatography: Fundamentals and Applications. Chromatographia 2016. [DOI: 10.1007/s10337-016-3167-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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18
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Salgado A, Chankvetadze B. Applications of nuclear magnetic resonance spectroscopy for the understanding of enantiomer separation mechanisms in capillary electrophoresis. J Chromatogr A 2016; 1467:95-144. [PMID: 27604161 DOI: 10.1016/j.chroma.2016.08.060] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 08/23/2016] [Accepted: 08/25/2016] [Indexed: 10/21/2022]
Abstract
This review deals with the applications of nuclear magnetic resonance (NMR) spectroscopy to understand the mechanisms of chiral separation in capillary electrophoresis (CE). It is accepted that changes observed in the separation process, including the reversal of enantiomer migration order (EMO), can be caused by subtle modifications in the molecular recognition mechanisms between enantiomer and chiral selector. These modifications may imply minor structural differences in those selector-selectand complexes that arise from the above mentioned interactions. Therefore, it is mandatory to understand the fine intermolecular interactions between analytes and chiral selectors. In other words, it is necessary to know in detail the structures of the complexes formed by the enantiomer (selectand) and the selector. Any differences in the structures of these complexes arising from either enantiomer should be detected, so that enantiomeric bias in the separation process could be explained. As to the nature of these interactions, those have been extensively reviewed, and it is not intended to be discussed here. These interactions contemplate ionic, ion-dipole and dipole-dipole interactions, hydrogen bonding, van der Waals forces, π-π stacking, steric and hydrophobic interactions. The main subject of this review is to describe how NMR spectroscopy helps to gain insight into the non-covalent intermolecular interactions between selector and selectand that lead to enantiomer separation by CE. Examples in which diastereomeric species are created by covalent (irreversible) derivatization will not be considered here. This review is structured upon the different structural classes of chiral selectors employed in CE, in which NMR spectroscopy has made substantial contributions to rationalize the observed enantioseparations. Cases in which other techniques complement NMR spectroscopic data are also mentioned.
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Affiliation(s)
- Antonio Salgado
- Centro de Espectroscopía de RMN (CERMN), Faculty of Pharmacy, University of Alcalá, University Campus, 28805 Alcalá de Henares, Madrid, Spain.
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia
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Escuder-Gilabert L, Martín-Biosca Y, Medina-Hernández MJ, Sagrado S. Enantioresolution in electrokinetic chromatography-complete filling technique using sulfated gamma-cyclodextrin. Software-free topological anticipation. J Chromatogr A 2016; 1467:391-399. [PMID: 27334416 DOI: 10.1016/j.chroma.2016.06.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 05/30/2016] [Accepted: 06/08/2016] [Indexed: 10/21/2022]
Abstract
Few papers have tried to predict the resolution ability of chiral selectors in capillary electrophoresis for the separation of the enantiomers of chiral compounds. In a previous work, we have used molecular information available on-line to establish enantioresolution levels of basic compounds using highly sulfated β-CD (HS-β-CD) as chiral selector in electrokinetic chromatography-complete filling technique (EKC-CFT). The present study is a continuation of this previous work, introducing some novelties. In this work, the ability of sulfated γ-cyclodextrin (S-γ-CD) as chiral selector in EKC-CFT is modelled for the first time. Thirty-three structurally unrelated cationic and neutral compounds (drugs and pesticides) are studied. Categorical enantioresolution levels (RsC, 0 or 1) are assigned from experimental enantioresolution values obtained at different S-γ-CD concentrations. Novel topological parameters connected to the chiral carbon (C*-parameters) are introduced. Four C*-parameters and a topological parameter of the whole molecule (aromatic atom count) are the most important variables according to a discriminant partial least squares-variable selection process. It suggests the preponderance of the topology adjacent to the chiral carbon to anticipate the RsC levels. A software-free anticipation protocol for new molecules is proposed. Over the current set of molecules evaluated, 100% of correct anticipations (resolved and non-resolved compounds) are obtained, while anticipation of some compounds remains undetermined. A criterion is introduced to alert on compounds which should not be anticipated.
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Affiliation(s)
| | - Yolanda Martín-Biosca
- Departamento de Química Analítica, Universitat de València, Burjassot, Valencia, Spain
| | | | - Salvador Sagrado
- Departamento de Química Analítica, Universitat de València, Burjassot, Valencia, Spain; Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Valencia, Spain
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Scriba GKE. Chiral recognition in separation science - an update. J Chromatogr A 2016; 1467:56-78. [PMID: 27318504 DOI: 10.1016/j.chroma.2016.05.061] [Citation(s) in RCA: 182] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 05/17/2016] [Accepted: 05/19/2016] [Indexed: 12/26/2022]
Abstract
Stereospecific recognition of chiral molecules is an important issue in various aspects of life sciences and chemistry including analytical separation sciences. The basis of analytical enantioseparations is the formation of transient diastereomeric complexes driven by hydrogen bonds or ionic, ion-dipole, dipole-dipole, van der Waals as well as π-π interactions. Recently, halogen bonding was also described to contribute to selector-selectand complexation. Besides structure-separation relationships, spectroscopic techniques, especially NMR spectroscopy, as well as X-ray crystallography have contributed to the understanding of the structure of the diastereomeric complexes. Molecular modeling has provided the tool for the visualization of the structures. The present review highlights recent contributions to the understanding of the binding mechanism between chiral selectors and selectands in analytical enantioseparations dating between 2012 and early 2016 including polysaccharide derivatives, cyclodextrins, cyclofructans, macrocyclic glycopeptides, proteins, brush-type selectors, ion-exchangers, polymers, crown ethers, ligand-exchangers, molecular micelles, ionic liquids, metal-organic frameworks and nucleotide-derived selectors. A systematic compilation of all published literature on the various chiral selectors has not been attempted.
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Affiliation(s)
- Gerhard K E Scriba
- Friedrich Schiller University Jena, Department of Pharmaceutical/Medicinal Chemistry, Philosophenweg 14, 07743 Jena, Germany.
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21
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Ali I, Suhail M, Al-Othman ZA, Alwarthan A, Aboul-Enein HY. Enantiomeric resolution of multiple chiral centres racemates by capillary electrophoresis. Biomed Chromatogr 2016; 30:683-94. [PMID: 26840015 DOI: 10.1002/bmc.3691] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 01/29/2016] [Accepted: 01/29/2016] [Indexed: 11/11/2022]
Abstract
Enantiomeric resolution of multichiral centre racemates is an important area as some multichiral centre racemates are of great medicinal importance. However, enantioseparation of such types of racemates is a challenging task. Amongst many analytical techniques, capillary electrophoresis is a powerful technique and may be used to resolve such racemates. Only few papers are available describing enantiomeric resolution of such racemates. Therefore, efforts have been made to describe the enantiomeric resolution of multichiral centre racemates by capillary electrophoresis. This article discusses the importance of multichiral racemates, the need for capillary electrophoresis in enantiomeric resolution and chiral resolution of multichiral centre racemates using various chiral selectors. Further, attempts have been made to discuss the future challenges and prospects of enantiomeric resolution of multichiral racemates. The various chiral selectors used for the purpose are chiral crown ether, cyclodextrins, polysaccharides, macrocyclic glycopeptide antibiotics and ligand exchange.
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Affiliation(s)
- Imran Ali
- Department of Chemistry, Jamia Millia Islamia (Central University), New Delhi, 110025, India
| | - Mohd Suhail
- Department of Chemistry, Jamia Millia Islamia (Central University), New Delhi, 110025, India
| | - Zeid A Al-Othman
- Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Kingdom of Saudi Arabia
| | - Abdulrahman Alwarthan
- Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Kingdom of Saudi Arabia
| | - Hassan Y Aboul-Enein
- Pharmaceutical and Medicinal Chemistry Department, Pharmaceutical and Drug Industries Research Division, National Research Centre, Dokki, Cairo, 12311, Egypt
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22
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Affiliation(s)
- Rachel K Harstad
- University of Minnesota , Department of Chemistry, 207 Pleasant Street South East, Minneapolis, Minnesota 55455, United States
| | - Alexander C Johnson
- University of Minnesota , Department of Chemistry, 207 Pleasant Street South East, Minneapolis, Minnesota 55455, United States
| | - Megan M Weisenberger
- University of Minnesota , Department of Chemistry, 207 Pleasant Street South East, Minneapolis, Minnesota 55455, United States
| | - Michael T Bowser
- University of Minnesota , Department of Chemistry, 207 Pleasant Street South East, Minneapolis, Minnesota 55455, United States
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Melani F, Pasquini B, Caprini C, Gotti R, Orlandini S, Furlanetto S. Combination of capillary electrophoresis, molecular modeling and NMR to study the enantioselective complexation of sulpiride with double cyclodextrin systems. J Pharm Biomed Anal 2015; 114:265-71. [DOI: 10.1016/j.jpba.2015.05.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 05/22/2015] [Accepted: 05/28/2015] [Indexed: 01/02/2023]
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24
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Chiral selectors in CE: Recent developments and applications (2012-mid 2014). Electrophoresis 2014; 36:101-23. [DOI: 10.1002/elps.201400310] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/25/2014] [Accepted: 09/26/2014] [Indexed: 12/19/2022]
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25
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Tabani H, Mahyari M, Sahragard A, Fakhari AR, Shaabani A. Evaluation of sulfated maltodextrin as a novel anionic chiral selector for the enantioseparation of basic chiral drugs by capillary electrophoresis. Electrophoresis 2014; 36:305-11. [PMID: 25262990 DOI: 10.1002/elps.201400370] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 09/02/2014] [Accepted: 09/19/2014] [Indexed: 11/07/2022]
Abstract
Introducing a new class of chiral selectors is an interesting work and this issue is still one of the hot topics in separation science and chirality. In this study, for the first time, sulfated maltodextrin (MD) was synthesized as a new anionic chiral selector and then it was successfully applied for the enantioseparation of five basic drugs (amlodipine, hydroxyzine, fluoxetine, tolterodine, and tramadol) as model chiral compounds using CE. This chiral selector has two recognition sites: a helical structure and a sulfated group which contribute to three corresponding driving forces; inclusion complexation, electrostatic interaction, and hydrogen binding. Under the optimized condition (buffer solution: 50 mM phosphate (pH 3.0) and 2% w/v sulfated MD; applied voltage: 18 kV; temperature: 20°C), baseline enantioseparation was observed for all mentioned chiral drugs. When instead of sulfated MD neutral MD was used under the same condition, no enantioseparation was observed which means the resolution power of sulfated MD is higher than neutral MD due to the electrostatic interaction between sulfated groups and protonated chiral drugs. Also, the countercurrent mobility of negatively charged MD (sulfated MD) allows more interactions between the chiral selector and chiral drugs and this in turn results in a successful resolution for the enantiomers. Furthermore, a higher concentration of neutral MD (approximately five times) is necessary to achieve the equivalent resolution compared with the negatively charged MD.
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Affiliation(s)
- Hadi Tabani
- Department of Pure Chemistry, Faculty of Chemistry, Shahid Beheshti University, Evin, Tehran, I.R. Iran
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26
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Huang J, Su P, Wu J, Yang Y. Enantioselective absorption of enantiomers with maleic anhydride-β-cyclodextrin modified magnetic microspheres. RSC Adv 2014. [DOI: 10.1039/c4ra12133c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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27
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Chen CY, Liu YC, Chien IC, Hsueh CC, Lin CH. Separation and Migration Behavior of Dichlorophenols in β-Cyclodextrin-Modified Capillary Zone Electrophoresis. J CHIN CHEM SOC-TAIP 2014. [DOI: 10.1002/jccs.201400085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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28
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Interactions of non-charged tadalafil stereoisomers with cyclodextrins: capillary electrophoresis and nuclear magnetic resonance studies. J Chromatogr A 2014; 1363:348-55. [PMID: 25193174 DOI: 10.1016/j.chroma.2014.08.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/12/2014] [Accepted: 08/13/2014] [Indexed: 11/21/2022]
Abstract
The single isomer drug R,R-tadalafil (Cialis) contains two chiral centers thus four stereoisomers (R,R-, S,S-, S,R- and R,S-tadalafil) exist, however, only the most potent inhibitor, the R,R-tadalafil is in clinical use. In our study, over 20 charged cyclodextrin (CD) derivatives were studied for enantiospecific host-guest type interactions in CD-modified capillary electrophoresis. Tadalafil stereoisomers are non-charged; therefore, their electrophoretic separation poses a challenge. Several candidates of both positively and negatively charged hosts were found to be effective for the enantioseparation. Eight out of the beta derivatives and three of alpha derivatives (including sulfated, sulfoalkylated, carboxyalkylated and amino derivatives) resolved all four stereoisomers partially or completely. Cavity size-dependent absolute enantiomer migration order (EMO) reversals were observed in the case of sulfopropyl-alpha (EMO: R,S; S,R; R,R; S,S) and sulfopropyl-beta (S,S; R,R; S,R; R,S) derivatives, while substituent-dependent partial EMO reversals were detected for sulfobutyl-ether-alpha (R,S; S,R; S,S; R,R) and sulfated-alpha-CD (R,R; S,S; R,S; S,R) selectors. Complexation-induced (1)H NMR chemical shift changes reflected that the benzodioxole moiety plays a major role in cavity size-dependent EMO reversal. Sulfobutyl-ether-alpha-CD was the only selector that provided the desired EMO in which the clinically applied eutomer R,R-tadalafil migrates last. Finally, an electrophoretic method applying a background electrolyte (BGE) containing 75 mM Tris-acetic acid buffer (pH 4.75) and 7 mM sulfobutyl-ether-alpha-CD was developed for the baseline resolution of all isomers at 25 °C and +25 kV applied voltage.
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Tabani H, Fakhari AR, Nojavan S. Maltodextrins as chiral selectors in CE: molecular structure effect of basic chiral compounds on the enantioseparation. Chirality 2014; 26:620-8. [PMID: 25065695 DOI: 10.1002/chir.22344] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 05/06/2014] [Indexed: 11/09/2022]
Abstract
Prediction of chiral separation for a compound using a chiral selector is an interesting and debatable work. For this purpose, in this study 23 chiral basic drugs with different chemical structures were selected as model solutes and the influence of their chemical structures on the enantioseparation in the presence of maltodextrin (MD) as chiral selector was investigated. For chiral separation, a 100-mM phosphate buffer solution (pH 3.0) containing 10% (w/v) MD with dextrose equivalent (DE) of 4-7 as chiral selector at the temperature of 25°C and voltage of 20 kV was used. Under this condition, baseline separation was achieved for nine chiral compounds and partial separation was obtained for another six chiral compounds while no enantioseparation was obtained for the remaining eight compounds. The results showed that the existence of at least two aromatic rings or cycloalkanes and an oxygen or nitrogen atom or -CN group directly bonded to the chiral center are necessary for baseline separation. With the obtained results in this study, chiral separation of a chiral compound can be estimated with MD-modified capillary electrophoresis before analysis. This prediction will minimize the number of preliminary experiments required to resolve enantiomers and will save time and cost.
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Affiliation(s)
- Hadi Tabani
- Department of Pure Chemistry, Faculty of Chemistry, Shahid Beheshti University, G. C., P.O. Box 19396-4716, Evin, Tehran, I.R., Iran
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Aranyi A, Péter A, Ilisz I, Fülöp F, Scriba GKE. Cyclodextrin-mediated enantioseparation of phenylalanine amide derivatives and amino alcohols by capillary electrophoresis-Role of complexation constants and complex mobilities. Electrophoresis 2014; 35:2848-54. [DOI: 10.1002/elps.201400142] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 05/22/2014] [Accepted: 05/24/2014] [Indexed: 02/03/2023]
Affiliation(s)
- Anita Aranyi
- Department of Inorganic and Analytical Chemistry; University of Szeged; Szeged Hungary
- Department of Pharmaceutical Chemistry; Friedrich Schiller University of Jena; Jena Germany
| | - Antal Péter
- Department of Inorganic and Analytical Chemistry; University of Szeged; Szeged Hungary
| | - István Ilisz
- Department of Inorganic and Analytical Chemistry; University of Szeged; Szeged Hungary
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry; University of Szeged; Szeged Hungary
| | - Gerhard K. E. Scriba
- Department of Pharmaceutical Chemistry; Friedrich Schiller University of Jena; Jena Germany
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31
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Řezanka P, Navrátilová K, Řezanka M, Král V, Sýkora D. Application of cyclodextrins in chiral capillary electrophoresis. Electrophoresis 2014; 35:2701-21. [DOI: 10.1002/elps.201400145] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 05/14/2014] [Accepted: 05/19/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Pavel Řezanka
- Department of Analytical Chemistry; Institute of Chemical Technology; Prague Czech Republic
| | - Klára Navrátilová
- Department of Analytical Chemistry; Institute of Chemical Technology; Prague Czech Republic
| | - Michal Řezanka
- Institute for Nanomaterials; Advanced Technologies and Innovation; Technical University of Liberec; Liberec Czech Republic
| | - Vladimír Král
- Department of Analytical Chemistry; Institute of Chemical Technology; Prague Czech Republic
| | - David Sýkora
- Department of Analytical Chemistry; Institute of Chemical Technology; Prague Czech Republic
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32
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Sánchez-López E, Salgado A, Crego AL, Marina ML. Investigation on the enantioseparation of duloxetine by capillary electrophoresis, NMR, and mass spectrometry. Electrophoresis 2014; 35:2842-7. [DOI: 10.1002/elps.201300656] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/12/2014] [Accepted: 03/18/2014] [Indexed: 11/07/2022]
Affiliation(s)
- Elena Sánchez-López
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology; Environmental Sciences and Chemistry, University of Alcalá; Madrid Spain
| | - Antonio Salgado
- Center of Applied Chemistry and Biotechnology (CQAB); University of Alcalá; Madrid Spain
| | - Antonio L. Crego
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology; Environmental Sciences and Chemistry, University of Alcalá; Madrid Spain
| | - María Luisa Marina
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology; Environmental Sciences and Chemistry, University of Alcalá; Madrid Spain
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33
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Hu SQ, Yang HB, Shi HJ, Zhang YH, Yang Z. Separation of palonosetron stereoisomers by electrokinetic chromatography using sodium cholate as chiral selector: Comparison of separation modes and elucidation of migration orders. Electrophoresis 2013; 34:3086-90. [DOI: 10.1002/elps.201300105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 06/10/2013] [Accepted: 06/26/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Shao-Qiang Hu
- College of Chemistry and Chemical Engineering; Luoyang Normal University; Luoyang; P. R. China
| | - Hong-Bing Yang
- College of Chemistry and Chemical Engineering; Luoyang Normal University; Luoyang; P. R. China
| | - Hai-Jun Shi
- Jiuquan Entry-Exit Inspection and Quarantine Bureau; Jiuquan; P. R. China
| | - Yong-Hua Zhang
- College of Chemistry and Chemical Engineering; Luoyang Normal University; Luoyang; P. R. China
| | - Zhuo Yang
- College of Chemistry and Chemical Engineering; Luoyang Normal University; Luoyang; P. R. China
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34
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Uccello-Barretta G, Balzano F. Chiral NMR Solvating Additives for Differentiation of Enantiomers. Top Curr Chem (Cham) 2013; 341:69-131. [DOI: 10.1007/128_2013_445] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Abstract
Capillary electrophoresis (CE) has matured to one of the major liquid phase enantiodifferentiation techniques since the first report in 1985. This can be primarily attributed to the flexibility as well as the various modes available including electrokinetic chromatography (EKC), micellar electrokinetic chromatography (MEKC), and microemulsion electrokinetic chromatography (MEEKC). In contrast to chromatographic techniques, the chiral selector is mobile in the background electrolyte. Furthermore, a large variety of chiral selectors are available that can be easily combined in the same separation system. In addition, the migration order of the enantiomers can be adjusted by a number of approaches. In CE enantiodifferentiations the separation principle is comparable to chromatography while the principle of the movement of the analytes in the capillary is based on electrophoretic phenomena. The present chapter will focus on mechanistic aspects of CE enantioseparations including enantiomer migration order and the current understanding of selector-selectand structures. Selected examples of the basic enantioseparation modes EKC, MEKC, and MEEKC will be discussed.
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Affiliation(s)
- Gerhard K E Scriba
- Department of Pharmaceutical/Medicinal Chemistry, Friedrich Schiller University Jena, Philosophenweg 14, 07743, Jena, Germany,
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36
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Jáč P, Scriba GKE. Recent advances in electrodriven enantioseparations. J Sep Sci 2012; 36:52-74. [DOI: 10.1002/jssc.201200836] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Revised: 09/22/2012] [Accepted: 09/22/2012] [Indexed: 01/05/2023]
Affiliation(s)
- Pavel Jáč
- Department of Pharmaceutical Chemistry; School of Pharmacy; Friedrich Schiller University; Jena; Germany
| | - Gerhard K. E. Scriba
- Department of Pharmaceutical Chemistry; School of Pharmacy; Friedrich Schiller University; Jena; Germany
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Chankvetadze L, Servais AC, Fillet M, Salgado A, Crommen J, Chankvetadze B. Comparative enantioseparation of talinolol in aqueous and non-aqueous capillary electrophoresis and study of related selector-selectand interactions by nuclear magnetic resonance spectroscopy. J Chromatogr A 2012; 1267:206-16. [PMID: 22964050 DOI: 10.1016/j.chroma.2012.08.063] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 08/17/2012] [Accepted: 08/21/2012] [Indexed: 10/27/2022]
Abstract
The enantiomers of the chiral β-blocker drug talinolol were separated with two single component sulfated β-cyclodextrin (CD) derivatives, namely heptakis (2,3-di-O-methyl-6-sulfo)-β-CD) (HDMS-β-CD) and heptakis (2,3-di-O-acetyl-6-sulfo)-β-CD) (HDAS-β-CD), in aqueous and non-aqueous capillary electrophoresis (CE). The enantiomer affinity pattern of talinolol toward these two CDs was opposite in both aqueous and non-aqueous CE. However, the enantiomer affinity pattern for a given CD derivative did not change when aqueous buffer was replaced with non-aqueous background electrolyte. The structures of the analyte-selector complexes in both, aqueous and non-aqueous electrolytes were studied using rotating frame nuclear Overhauser effect (ROESY) NMR spectroscopy. Inclusion complex formation between the enantiomers of talinolol and HDAS-β-CD was confirmed in aqueous buffer, while the complex between the enantiomers of talinolol and HDMS-β-CD was of the external type. The complex of the talinolol enantiomers with HDAS-β-CD in non-aqueous electrolyte was also of the external type. In spite of external complex formation excellent separation of the enantiomers was observed in non-aqueous CE.
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Affiliation(s)
- Lali Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Tbilisi, Georgia
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