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de Koster N, Clark CP, Kohler I. Past, present, and future developments in enantioselective analysis using capillary electromigration techniques. Electrophoresis 2021; 42:38-57. [PMID: 32914880 PMCID: PMC7821218 DOI: 10.1002/elps.202000151] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/22/2020] [Accepted: 09/08/2020] [Indexed: 12/16/2022]
Abstract
Enantioseparation of chiral products has become increasingly important in a large diversity of academic and industrial applications. The separation of chiral compounds is inherently challenging and thus requires a suitable analytical technique that can achieve high resolution and sensitivity. In this context, CE has shown remarkable results so far. Chiral CE offers an orthogonal enantioselectivity and is typically considered less costly than chromatographic techniques, since only minute amounts of chiral selectors are needed. Several CE approaches have been developed for chiral analysis, including chiral EKC and chiral CEC. Enantioseparations by EKC benefit from the wide variety of possible pseudostationary phases that can be employed. Chiral CEC, on the other hand, combines chromatographic separation principles with the bulk fluid movement of CE, benefitting from reduced band broadening as compared to pressure-driven systems. Although UV detection is conventionally used for these approaches, MS can also be considered. CE-MS represents a promising alternative due to the increased sensitivity and selectivity, enabling the chiral analysis of complex samples. The potential contamination of the MS ion source in EKC-MS can be overcome using partial-filling and counter-migration techniques. However, chiral analysis using monolithic and open-tubular CEC-MS awaits additional method validation and a dedicated commercial interface. Further efforts in chiral CE are expected toward the improvement of existing techniques, the development of novel pseudostationary phases, and establishing the use of chiral ionic liquids, molecular imprinted polymers, and metal-organic frameworks. These developments will certainly foster the adoption of CE(-MS) as a well-established technique in routine chiral analysis.
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Affiliation(s)
- Nicky de Koster
- Leiden Academic Centre for Drug Research, Division of Systems Biomedicine and PharmacologyLeiden UniversityLeidenThe Netherlands
| | - Charles P. Clark
- Leiden Academic Centre for Drug Research, Division of Systems Biomedicine and PharmacologyLeiden UniversityLeidenThe Netherlands
| | - Isabelle Kohler
- Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Amsterdam Institute for Molecular and Life SciencesVrije Universiteit AmsterdamAmsterdamThe Netherlands
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2
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Fanali S, Chankvetadze B. History, advancement, bottlenecks, and future of chiral capillary electrochromatography. J Chromatogr A 2020; 1637:461832. [PMID: 33383238 DOI: 10.1016/j.chroma.2020.461832] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 02/06/2023]
Abstract
Capillary electrochromatography (CEC) represents a technique with less than 30 years of intense development and in this period this technique has seen huge promise, fast development, stagnation, and significant decline of innovative activity. The major goal of the present overview is not to present an extensive review of the literature on chiral CEC but to analyze the reasons for this dramatic development and attempting to answer questions such as: 1) Was the potential of CEC reasonably evaluated in 1990s before starting the explosive development in this field? 2) Did the development of this technique take the right track? 3) What other developments and competitive trends led to stagnation in the advancement of CEC? 4) Why is the activity in this field currently decreasing? 5) What are the current challenges and promises and what is the future of chiral CEC?
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Affiliation(s)
- Salvatore Fanali
- Teaching Committee of Ph.D. School in Natural Science and Engineering, University of Verona, Strada Le Grazie, 15, 37129 Verona, Italy
| | - 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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3
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D'Orazio G, Fanali C, Fanali S, Gentili A, Karchkhadze M, Chankvetadze B. Further study on enantiomer resolving ability of amylose tris(3-chloro-5-methylphenylcarbamate) covalently immobilized onto silica in nano-liquid chromatography and capillary electrochromatography. J Chromatogr A 2020; 1623:461213. [PMID: 32505297 DOI: 10.1016/j.chroma.2020.461213] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/02/2020] [Accepted: 05/05/2020] [Indexed: 10/24/2022]
Abstract
In the present study separation of enantiomers of some chiral neutral, basic and weakly acidic analytes was investigated on the chiral stationary phase (CSP) made by covalent immobilization of amylose tris(3-chloro-5-methylphenylcarbamate) onto aminopropylsilanized (APS) silica in nano-liquid chromatography (nano-LC) in aqueous methanol or acetonitrile mixtures. It has been shown that similar to high-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC) this chiral selector is useful for separation of enantiomers of neutral, basic and acidic analytes also in nano-LC. In comparison to our previous research, in which the chiral selector (CS) was bonded on native silica, in this study, the CS was immobilized on APS silica in order to improve chromatographic performance towards basic analytes. In fact, some improvement was observed and surprisingly not only for basic but also for neutral and acidic analytes. Again, quite unexpectedly almost no electroosmotic flow (EOF) was observed in capillaries packed with ca. 20% (w/w) amylose tris(3-chloro-5-methylphenylcarbamate) immobilized onto APS silica although the same APS silica before attachment of chiral selector exhibited significant EOF. In order to generate EOF in the capillaries with the CSP and enable capillary electrochromatographic (CEC) experiment on it, the short segment of the capillary column was packed with APS silica without chiral selector. The EOF in such capillary enabled CEC experiment and some preliminary results are reported here.
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Affiliation(s)
- Giovanni D'Orazio
- Istituto per i Sistemi Biologici (ISB), CNR- Consiglio Nazionale delle Ricerche, Via Salaria Km 29,300 - 00015 Monterotondo (Rome), Italy
| | - Chiara Fanali
- Department of Science and Technology for Humans and the Environment, University Campus Bio-Medico of Rome, Via Alvaro del Portillo 21, 00128 Rome, Italy
| | - Salvatore Fanali
- Teaching Committee of Ph.D. School in Natural Science and Engineering, University of Verona, Strada Le Grazie, 15 - 37129 Verona, Italy.
| | - Alessandra Gentili
- Department of Chemistry "Sapienza" University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Marina Karchkhadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Iv. Javakhishvili Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Iv. Javakhishvili Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia
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4
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Chankvetadze B. Recent trends in preparation, investigation and application of polysaccharide-based chiral stationary phases for separation of enantiomers in high-performance liquid chromatography. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2019.115709] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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5
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Echevarría RN, Keunchkarian S, Villarroel-Rocha J, Sapag K, Reta M. Organic monolithic capillary columns coated with cellulose tris(3,5-dimethylphenyl carbamate) for enantioseparations by capillary HPLC. Microchem J 2019. [DOI: 10.1016/j.microc.2019.104011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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6
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Comparative study on enantiomer resolving ability of amylose tris(3-chloro-5-methylphenylcarbamate) covalently immobilized onto silica in nano-liquid chromatography and capillary electrochromatography. J Chromatogr A 2019; 1606:460425. [PMID: 31471135 DOI: 10.1016/j.chroma.2019.460425] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 08/02/2019] [Accepted: 08/03/2019] [Indexed: 12/14/2022]
Abstract
In the present study separation of enantiomers of some chiral neutral and weakly acidic analytes was investigated on the chiral stationary phase (CSP) made by covalent immobilization of amylose tris(3-chloro-5-methylphenylcarbamate) onto silica in nano-liquid chromatography (nano-LC) and capillary electrochromatography (CEC) in acetonitrile and aqueous acetonitrile. Few comparisons were made also between the enantioseparations in nano-LC and high-performance liquid chromatography (HPLC) with the chiral column of 4.6 × 250 mm dimension. Slightly better separation of enantiomers was observed in HPLC mode compared to nano-LC mode. It was shown that in the capillary columns packed with the CSP containing about 20% (w/w) of a covalently immobilized neutral chiral selector, amylose tris(3-chloro-5-methylphenylcarbamate), sufficient electroosmotic flow has been generated and enantioseparations with reasonable analysis time were performed also in CEC mode. It was shown once again that CEC offers a clear advantage over nano-LC from the viewpoint of plate numbers and peak resolution.
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7
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D' Orazio G, Asensio-Ramos M, Fanali C. Enantiomers separation by capillary electrochromatography using polysaccharide-based stationary phases. J Sep Sci 2018; 42:360-384. [PMID: 30198206 DOI: 10.1002/jssc.201800798] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/03/2018] [Accepted: 09/03/2018] [Indexed: 01/16/2023]
Abstract
The separation of chiral compounds is an interesting and important topic of research because these compounds are involved in some biological processes, fundamentally in human health. Among the various application fields where enantiomers are remarkable, drug analysis has to be considered. Most of the drugs contain enantiomers and very often one of the two isomers could be pharmacologically more active or even dangerous. Therefore, the separation of these compounds is very important. Among the different analytical techniques usually employed, capillary electrochromatography has demonstrated great capability in enantiomers resolution. The great potential of this electromigration technique stands mainly in its high efficiency due to the use of an electrosmotic flow (flat flow profile) and on the high selectivity because of the use of a stationary phase. Chiral separation can be obtained utilizing several chiral stationary phases including a polysaccharide derivative. The aim of this review paper is to summarize the main features of capillary electrochromatography and polysaccharide derivatives of chiral stationary phase. It also report examples of practical applications utilizing this approach.
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Affiliation(s)
- Giovanni D' Orazio
- Institute of Chemical Methodologies, Italian National Research Council (C.N.R.), Monterotondo, Italy
| | - María Asensio-Ramos
- Instituto Volcanológico de Canarias (INVOLCAN), Puerto de la Cruz, Tenerife, Spain
| | - Chiara Fanali
- Department of Medicine, University Campus Bio-Medico of Rome, Rome, Italy
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8
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Jin X, Kang Q, Wang Y. Enantioseparation of Flavanoids, Isoxazolines, Dansyl Amino Acids and β-Blockers on Native and Phenylcarbamoylated α, β and γ-Cyclodextrin Chiral Stationary Phases. ChemistrySelect 2017. [DOI: 10.1002/slct.201701847] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Xuan Jin
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300072 China
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science; Tianjin University; Tianjin 300072 China
| | - Qing Kang
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300072 China
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science; Tianjin University; Tianjin 300072 China
| | - Yong Wang
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300072 China
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science; Tianjin University; Tianjin 300072 China
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9
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Postpolymerization modification of a hydroxy monolith precursor. Part III. Activation of poly(hydroxyethyl methacrylate-co-pentaerythritol triacrylate) monolith with epoxy functionalities followed by bonding of glycerol, polyamines, and hydroxypropyl-β-cy. Electrophoresis 2016; 37:3178-3185. [DOI: 10.1002/elps.201600326] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 08/29/2016] [Accepted: 09/01/2016] [Indexed: 12/29/2022]
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10
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Further proof to the utility of polysaccharide-based chiral selectors in combination with superficially porous silica particles as effective chiral stationary phases for separation of enantiomers in high-performance liquid chromatography. J Chromatogr A 2016; 1467:163-168. [DOI: 10.1016/j.chroma.2016.08.046] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 08/19/2016] [Accepted: 08/20/2016] [Indexed: 11/21/2022]
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11
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Fanali C, Fanali S. Chiral Separations using Miniaturized Techniques: State of the Art and Perspectives. Isr J Chem 2016. [DOI: 10.1002/ijch.201600061] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Chiara Fanali
- Centro Integrato di Ricerca; Campus Bio-Medico University; Rome (Italy)
| | - Salvatore Fanali
- Institute of Chemical Methodologies; Italian National Research Council (CNR); Area della Ricerca di Roma I; Via Salaria km. 29.300-00015 Monterotondo, Rome (Italy)
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12
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Enantioseparations in open-tubular capillary electrochromatography: Recent advances and applications. J Chromatogr A 2016; 1467:145-154. [PMID: 27461922 DOI: 10.1016/j.chroma.2016.07.039] [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: 04/14/2016] [Revised: 07/14/2016] [Accepted: 07/15/2016] [Indexed: 12/25/2022]
Abstract
This review highlights recent advances and applications in open-tubular capillary electrochromatography (OT-CEC) for enantioseparations during the last decade. Although extensive research has been conducted in the area of separations by use of CEC, and a big number of reviews have been published, there is not a review on exclusively the use of chiral stationary phases (CSPs) in OT-CEC for enantioseparations. Therefore, in this review, the design and synthesis of different CSPs are presented, and their potential applications in OT-CEC for enantioseparations are discussed. The different approaches to CSP development include chiral nanomaterials, porous layers, molecular imprinting, sol-gel technique, polyelectrolyte multilayer coating, polymeric coating and others.
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13
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Ali I, Suhail M, Lone MN, Alothman ZA, Alwarthan A. Chiral resolution of multichiral center racemates by different modalities of chromatography. J LIQ CHROMATOGR R T 2016. [DOI: 10.1080/10826076.2016.1152582] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Imran Ali
- Department of Chemistry, Jamia Millia Islamia Central University, New Delhi, India
| | - Mohd Suhail
- Department of Chemistry, Jamia Millia Islamia Central University, New Delhi, India
| | - Mohammad Nadeem Lone
- Department of Chemistry, Jamia Millia Islamia Central University, New Delhi, India
| | - Zeid A. Alothman
- Department of Chemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Abdulrahman Alwarthan
- Department of Chemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
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14
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Declerck S, Vander Heyden Y, Mangelings D. Enantioseparations of pharmaceuticals with capillary electrochromatography: A review. J Pharm Biomed Anal 2016; 130:81-99. [PMID: 27156645 DOI: 10.1016/j.jpba.2016.04.024] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/13/2016] [Accepted: 04/17/2016] [Indexed: 11/19/2022]
Abstract
The chiral separation of pharmaceuticals is one of the major research topics in the pharmaceutical industry. Chromatographic techniques are most frequently used in this context. Separations in capillary electrochromatography (CEC) are an alternative and achieved by chromatographic retention and electrophoretic mobility principles. As a result, CEC is characterized by a high selectivity and efficiency. The limited number of stationary phases specifically developed for CEC, the low number of commercially available CEC columns, the frits to maintain the stationary phase, which forms fragile spots in the columns, and the limited column robustness and reproducibility, make CEC not very attractive for industrial application. However, CEC is still applied and studied in the academic field. This review discusses the enantioseparation of drugs in CEC published during the last four years, with a critical view on the reproducibility and the practical utility of these applications.
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Affiliation(s)
- Sven Declerck
- Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel-VUB, Laarbeeklaan 103, B-1090 Brussels, Belgium.
| | - Yvan Vander Heyden
- Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel-VUB, Laarbeeklaan 103, B-1090 Brussels, Belgium.
| | - Debby Mangelings
- Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel-VUB, Laarbeeklaan 103, B-1090 Brussels, Belgium.
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15
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Wang Y, Zhang S, Breitbach ZS, Petersen H, Ellegaard P, Armstrong DW. Enantioseparation of citalopram analogues with sulfated β-cyclodextrin by capillary electrophoresis. Electrophoresis 2016; 37:841-8. [DOI: 10.1002/elps.201500541] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/22/2015] [Accepted: 12/22/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Yadi Wang
- Department of Chemistry and Biochemistry; University of Texas at Arlington; Arlington TX USA
| | - Shusheng Zhang
- Department of Chemistry and Biochemistry; University of Texas at Arlington; Arlington TX USA
- College of Chemistry & Molecular Engineering; Zhengzhou University; Zhengzhou P. R. China
| | - Zachary S. Breitbach
- Department of Chemistry and Biochemistry; University of Texas at Arlington; Arlington TX USA
| | - Hans Petersen
- H. Lundbeck A/S, Chemical Process Research; Valby Denmark
| | | | - Daniel W. Armstrong
- Department of Chemistry and Biochemistry; University of Texas at Arlington; Arlington TX USA
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16
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Amino-functionalized silica nanoparticles for improved enantiomeric separation in capillary electrophoresis using carboxymethyl-β-cyclodextrin (CM-β-CD) as a chiral selector. Mikrochim Acta 2015. [DOI: 10.1007/s00604-015-1449-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Li W, Ding GS, Tang AN. Enantiomer separation of propranolol and tryptophan using bovine serum albumin functionalized silica nanoparticles as adsorbents. RSC Adv 2015. [DOI: 10.1039/c5ra17535f] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The immobilization of popular chiral selectors on the surface of nanomaterials to prepare new chiral adsorbents for preparative chiral separation is a research hotspot in separation science nowadays.
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Affiliation(s)
- Wei Li
- Research Center for Analytical Sciences
- College of Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
| | - Guo-Sheng Ding
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency
- School of Pharmaceutical Science and Technology
- Tianjin University
- Tianjin 300072
- P. R. China
| | - An-Na Tang
- Research Center for Analytical Sciences
- College of Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
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18
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Methods for separation of organic and pharmaceutical compounds by different polymer materials. KOREAN J CHEM ENG 2014. [DOI: 10.1007/s11814-014-0284-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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19
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Nageswara Rao R, Guru Prasad K. Stereo-specific LC and LC-MS bioassays of antidepressants and psychotics. Biomed Chromatogr 2014; 29:21-40. [DOI: 10.1002/bmc.3356] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 08/26/2014] [Accepted: 09/03/2014] [Indexed: 11/08/2022]
Affiliation(s)
- R. Nageswara Rao
- D215, Discovery Laboratory, Analytical Chemistry Division; Indian Institute of Chemical Technology; Tarnaka Hyderabad 500 607 India
| | - K. Guru Prasad
- D215, Discovery Laboratory, Analytical Chemistry Division; Indian Institute of Chemical Technology; Tarnaka Hyderabad 500 607 India
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20
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Effect of content of chiral selector and pore size of core–shell type silica support on the performance of amylose tris(3,5-dimethylphenylcarbamate)-based chiral stationary phases in nano-liquid chromatography and capillary electrochromatography. J Chromatogr A 2014; 1363:363-71. [DOI: 10.1016/j.chroma.2014.05.029] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/06/2014] [Accepted: 05/11/2014] [Indexed: 11/19/2022]
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21
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Aturki Z, Schmid MG, Chankvetadze B, Fanali S. Enantiomeric separation of new cathinone derivatives designer drugs by capillary electrochromatography using a chiral stationary phase, based on amylosetris(5-chloro-2-methylphenylcarbamate). Electrophoresis 2014; 35:3242-9. [DOI: 10.1002/elps.201400085] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/17/2014] [Accepted: 05/14/2014] [Indexed: 01/30/2023]
Affiliation(s)
- Zeineb Aturki
- Institute of Chemical Methodologies; Italian National Research Council; Monterotondo Rome Italy
| | - Martin G. Schmid
- Department of Pharmaceutical Chemistry; Institute of Pharmaceutical Sciences; Karl-Franzens-University Graz; Graz Austria
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Salvatore Fanali
- Institute of Chemical Methodologies; Italian National Research Council; Monterotondo Rome Italy
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22
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Hsieh ML, Chau LK, Hon YS. Single-step approach for fabrication of vancomycin-bonded silica monolith as chiral stationary phase. J Chromatogr A 2014; 1358:208-16. [PMID: 25047820 DOI: 10.1016/j.chroma.2014.07.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 06/28/2014] [Accepted: 07/02/2014] [Indexed: 12/01/2022]
Abstract
A vancomycin-bonded silica monolithic column for capillary electrochromatography (CEC) was prepared by a single-step in situ sol-gel approach. This sol-gel process incorporates a synthetic sol-gel precursor which contains a macrocyclic antibiotic, vancomycin, to form a porous silica network inside a fused-silica capillary. To avoid degradation of vancomycin during the column fabrication, a mild step was adopted into the sol-gel process. The performance of the vancomycin chiral stationary phase was investigated by CEC in both the reversed-phase mode and the normal-phase mode. The vancomycin chiral stationary phase was optimized with respect to vancomycin loading in the reversed-phase mode for chiral separation of thalidomide enantiomers. The best efficiency and resolution values of 94600plates/m and 5.79, respectively, were achieved. The optimized column was further applied to chiral separation of alprenolol enantiomers. A plate height of less than 7μm for the first eluted enantiomer of alprenolol was obtained in an aqueous mobile phase at a flow rate of 0.74mm/s. Using enantiomers of seven β-blockers and some other basic enantiomers as test analytes, separation efficiencies of up to 148100plates/m in the reversed-phase mode and up to 138100plates/m in the normal-phase mode were achieved.
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Affiliation(s)
- Ming-Lung Hsieh
- Department of Chemistry and Biochemistry, National Chung Cheng University, 168 University Road, Min-Hsiung, Chia-Yi 62102, Taiwan, ROC
| | - Lai-Kwan Chau
- Department of Chemistry and Biochemistry, National Chung Cheng University, 168 University Road, Min-Hsiung, Chia-Yi 62102, Taiwan, ROC; Center for Nano Bio-Detection and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, 168 University Road, Min-Hsiung, Chia-Yi 62102, Taiwan, ROC.
| | - Yung-Son Hon
- Department of Chemistry and Biochemistry, National Chung Cheng University, 168 University Road, Min-Hsiung, Chia-Yi 62102, Taiwan, ROC
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23
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Hong JS, Park JH. Chiral Separation of Basic Compounds on Sulfated β-Cyclodextrin-Coated Zirconia Monolith by Capillary Electrochromatography. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.6.1809] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Aydoğan C, Yılmaz F, Denizli A. Cation exchange/hydrophobic interaction monolithic chromatography of small molecules and proteins by nano liquid chromatography†. J Sep Sci 2013; 36:1685-92. [DOI: 10.1002/jssc.201300089] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/18/2013] [Accepted: 03/18/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Cemil Aydoğan
- Department of Chemistry; Biochemistry Division, Hacettepe University; Ankara; Turkey
| | - Fatma Yılmaz
- Vocational School of Gerede Chemistry Technology Division; Abant Izzet Baysal University; Bolu; Turkey
| | - Adil Denizli
- Department of Chemistry; Biochemistry Division, Hacettepe University; Ankara; Turkey
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25
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Rocco A, Maruška A, Fanali S. Enantiomeric separations by means of nano-LC. J Sep Sci 2013; 36:421-44. [DOI: 10.1002/jssc.201200886] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 10/24/2012] [Accepted: 10/26/2012] [Indexed: 11/05/2022]
Affiliation(s)
- Anna Rocco
- Department of Biochemistry and Biotechnologies; Vytautas Magnus University; Kaunas Lithuania
- Institute of Chemical Methodologies; Consiglio Nazionale delle Ricerche; Rome Italy
| | - Audrius Maruška
- Department of Biochemistry and Biotechnologies; Vytautas Magnus University; Kaunas Lithuania
| | - Salvatore Fanali
- Institute of Chemical Methodologies; Consiglio Nazionale delle Ricerche; Rome Italy
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Comparative performance of capillary columns made with totally porous and core–shell particles coated with a polysaccharide-based chiral selector in nano-liquid chromatography and capillary electrochromatography. J Chromatogr A 2012; 1269:136-42. [DOI: 10.1016/j.chroma.2012.06.021] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 06/06/2012] [Accepted: 06/07/2012] [Indexed: 11/18/2022]
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27
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Chankvetadze B. Recent developments on polysaccharide-based chiral stationary phases for liquid-phase separation of enantiomers. J Chromatogr A 2012; 1269:26-51. [DOI: 10.1016/j.chroma.2012.10.033] [Citation(s) in RCA: 329] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 10/11/2012] [Accepted: 10/15/2012] [Indexed: 10/27/2022]
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28
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Lee JM, Jang MD, Park JH. Chiral Separation on Sulfonated Cellulose Tris(3,5-dimethylphenylcarbamate)-coated Zirconia Monolith by Capillary Electrochromatography. B KOREAN CHEM SOC 2012. [DOI: 10.5012/bkcs.2012.33.8.2651] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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29
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Enantioseparation of chiral acids and bases on a clindamycin phosphate-modified zirconia monolith by capillary electrochromatography. J Chromatogr A 2012; 1251:244-248. [DOI: 10.1016/j.chroma.2012.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 05/25/2012] [Accepted: 06/02/2012] [Indexed: 11/22/2022]
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30
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31
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Jin Y, Chen C, Meng L, Chen J, Li M, Zhu Z. Simultaneous and sensitive capillary electrophoretic enantioseparation of three β-blockers with the combination of achiral ionic liquid and dual CD derivatives. Talanta 2012; 89:149-54. [DOI: 10.1016/j.talanta.2011.12.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 11/25/2011] [Accepted: 12/01/2011] [Indexed: 11/17/2022]
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32
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Aturki Z, D'Orazio G, Rocco A, Fanali S. Advances in the enantioseparation of β-blocker drugs by capillary electromigration techniques. Electrophoresis 2011; 32:2602-28. [PMID: 21905049 DOI: 10.1002/elps.201100153] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 04/08/2011] [Accepted: 04/09/2011] [Indexed: 11/07/2022]
Abstract
β-Blocker drugs or β-adrenergic blocking agents are an important class of drugs, prescribed with great frequency. They are used for various diseases, particularly for the treatment of cardiac arrhythmias, cardioprotection after myocardial infarction (heart attack), and hypertension. Almost all β-blocker drugs possess one or more stereogenic centers; however; only some of them are administered as single enantiomers. Since both enantiomers can differ in their pharmacological and toxicological properties, enantioselective analytical methods are required not only for pharmacodynamic and pharmacokinetic studies but also for quality control of pharmaceutical preparations with the determination of enantiomeric purity. In addition to the chromatographic tools, in recent years, capillary electromigration techniques (CE, CEC, and MEKC) have been widely used for enantioselective purposes employing a variety of chiral selectors, e.g. CDs, polysaccharides, macrocyclic antibiotics, proteins, chiral ion-paring agents, etc. The high separation efficiency, rapid analysi,s and low consumption of reagents of electromigration methods make them a very attractive alternative to the conventional chromatographic methods. In this review, the development and applications of electrodriven methods for the enantioseparation of β-blocker drugs are reported. The papers concerning this topic, published from January 2000 until December 2010, are summarised here. Particular attention is given to the coupling of chiral CE and CEC methods to MS, as this detector provides high sensitivity and selectivity.
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Affiliation(s)
- Zeineb Aturki
- Istituto di Metodologie Chimiche, Consiglio Nazionale delle Ricerche, Area della Ricerca di Roma, Monterotondo Scalo, Rome, Italy
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33
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Kumar AP, Park JH. Chiral separation of basic compounds on a cellulose 3,5-dimethylphenylcarbamate-coated zirconia monolithin basic eluents by capillary electrochromatography. J Chromatogr A 2011; 1218:6548-53. [DOI: 10.1016/j.chroma.2011.06.101] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 06/24/2011] [Accepted: 06/26/2011] [Indexed: 10/18/2022]
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34
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Mandrioli R, Mercolini L, Raggi MA. Chiral analysis of amphetamines, methadone and metabolites in biological samples by electrodriven methods. Electrophoresis 2011; 32:2629-39. [DOI: 10.1002/elps.201000687] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 03/14/2011] [Accepted: 03/20/2011] [Indexed: 11/07/2022]
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35
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Kumar AP, Park JH. Fast separations of chiral β-blockers on a cellulose tris(3,5-dimethylphenylcarbamate)-coated zirconia monolithic column by capillary electrochromatography. J Chromatogr A 2011; 1218:5369-73. [DOI: 10.1016/j.chroma.2011.06.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 05/16/2011] [Accepted: 06/01/2011] [Indexed: 10/18/2022]
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36
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Barbato F, Grumetto L, Carpentiero C, Rocco A, Fanali S. Capillary electrochromatography as a new tool to assess drug affinity for membrane phospholipids. J Pharm Biomed Anal 2011; 54:893-9. [DOI: 10.1016/j.jpba.2010.11.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 11/19/2010] [Accepted: 11/23/2010] [Indexed: 11/24/2022]
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37
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Monoliths with chiral surface functionalization for enantioselective capillary electrochromatography. J Pharm Biomed Anal 2010; 53:1091-123. [DOI: 10.1016/j.jpba.2010.05.026] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 05/25/2010] [Accepted: 05/26/2010] [Indexed: 11/23/2022]
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38
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Hendrickx A, Mangelings D, Chankvetadze B, Vander Heyden Y. Comparative enantioseparations of pharmaceuticals in capillary electrochromatography on polysaccharide-based chiral stationary phases containing selectors with or without chlorinated derivatives. Electrophoresis 2010; 31:3207-16. [DOI: 10.1002/elps.201000249] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Abstract
This review article addresses the developments and applications of capillary electromigration methods coupled on-line with MS for chiral analysis. The multiple enantiomeric applications of this hyphenated technology are covered including chiral analysis of drugs, food compounds, pesticides, natural metabolites, etc. in different matrices such as plasma, urine, medicines, foods, etc. This work intends to provide an updated overview (including works published till September 2009) on the principal chiral applications carried out by CZE-MS, CEC-MS and MEKC-MS, discussing their main advantages and drawbacks in all their different areas of application as well as their foreseeable development in the not too distant future.
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Affiliation(s)
- Carolina Simó
- Department of Food Analysis, Institute of Industrial Fermentations (CSIC), Madrid, Spain
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40
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Fanali S, D’Orazio G, Lomsadze K, Samakashvili S, Chankvetadze B. Enantioseparations on amylose tris(5-chloro-2-methylphenylcarbamate) in nano-liquid chromatography and capillary electrochromatography. J Chromatogr A 2010; 1217:1166-74. [DOI: 10.1016/j.chroma.2009.09.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 09/08/2009] [Accepted: 09/10/2009] [Indexed: 10/20/2022]
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41
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Mikus P, Maráková K. Advanced CE for chiral analysis of drugs, metabolites, and biomarkers in biological samples. Electrophoresis 2010; 30:2773-802. [PMID: 19653234 DOI: 10.1002/elps.200900173] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An analysis of recent trends indicates that CE can show real advantages over chromatographic methods in ultratrace enantioselective determination of biologically active compounds in complex biological matrices. It is due to high separation efficiency and many applicable in-capillary electromigration effects in CE (countercurrent migration, stacking effects) enhancing significantly (enantio)separability and enabling effective sample preparation (preconcentration, purification, analyte derivatization). Other possible on-line combinations of CE, such as column coupled CE-CE techniques and implementation of nonelectrophoretic techniques (extraction, membrane filtration, flow injection) into CE, offer additional approaches for highly effective sample preparation and separation. CE matured to a highly flexible and compatible technique enabling its hyphenation with powerful detection systems allowing extremely sensitive detection (e.g. LIF) and/or structural characterization of analytes (e.g. MS). Within the last decade, more as well as less conventional analytical on-line approaches have been effectively utilized in this field and their practical potentialities are demonstrated on many new application examples in this article. Here, three basic areas of (enantioselective) drug bioanalysis are highlighted and supported by a brief theoretical description of each individual approach in a compact review structure (to create integrated view on the topic), including (i) progressive enantioseparation approaches and new enantioselective agents, (ii) in-capillary sample preparation (preconcentration, purification, derivatization), and (iii) detection possibilities related to enhanced sensitivity and structural characterization.
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Affiliation(s)
- Peter Mikus
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic.
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42
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Buchinger S, Follrich B, Lämmerhofer M, Lubda D, Lindner W. Chirally functionalized anion-exchange type silica monolith for enantiomer separation of 2-aryloxypropionic acid herbicides by non-aqueous capillary electrochromatography. Electrophoresis 2009; 30:3804-13. [DOI: 10.1002/elps.200900379] [Citation(s) in RCA: 19] [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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43
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Si-Ahmed K, Tazerouti F, Badjah-Hadj-Ahmed AY, Aturki Z, D'Orazio G, Rocco A, Fanali S. Optical isomer separation of flavanones and flavanone glycosides by nano-liquid chromatography using a phenyl-carbamate-propyl-beta-cyclodextrin chiral stationary phase. J Chromatogr A 2009; 1217:1175-82. [PMID: 19699481 DOI: 10.1016/j.chroma.2009.07.053] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 07/23/2009] [Accepted: 07/27/2009] [Indexed: 11/17/2022]
Abstract
In this paper a phenyl-carbamate-propyl-beta-cyclodextrin stationary phase was employed for the enantioseparation of several flavonoids, including flavanones and methoxyflavanones by using nano-liquid chromatography (nano-LC). The same stationary phase was also used for the diastereoisomeric separation of two flavanone glycosides. The compounds: flavanone, 2'-hydroxyflavanone, 4'-hydroxyflavanone, 6-hydroxyflavanone, 7-hydroxyflavanone, 4'-methoxyflavanone, 6-methoxyflavanone, 7-methoxyflavanone, hesperetin, hesperidin, naringenin and naringin were studied using reversed, polar organic and normal elution modes. The effect of the nature and composition of the mobile phase (organic modifier type, buffer and water content in the reversed phase mode) on the enantioresolution (R(s)), retention factor (k) and enantioselectivity (alpha) were investigated. Baseline resolution of all studied flavonoids, with the exception of 2'-hydroxyflavanone and naringin, was achieved in reversed phase mode using a mixture of MeOH/H(2)O at different ratios as mobile phase. Good results, in terms of peak efficiency and short analysis time, were obtained adding 1% triethylammonium acetate pH 4.5 buffer to MeOH/H(2)O mixture. The separation of the studied compounds was also performed in polar organic mode. By using 100% of MeOH as mobile phase, the resolution was achieved for the studied analytes, except for 7-hydroxyflavanone, 2'-hydroxyflavanone, naringenin, hesperidin and naringin. Normal mode was tested employing a mixture of EtOH/hexane/TFA as mobile phase achieving the enantiomeric and diastereomeric separation of only hesperetin and hesperidin, respectively. The use of nano-LC technique for the resolution of flavanones optical isomers allowed to achieve good resolutions in shorter analysis time compared to the results reported in literature with conventional HPLC.
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Affiliation(s)
- Kahina Si-Ahmed
- Institute of Chemical Methodologies, Italian National Council of Research, Area della Ricerca di Roma, Via Salaria Km 29, 300-00015 Monterotondo Scalo, Rome, Italy
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44
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Wang Y, Xiao Y, Tan TTY, Ng SC. Application of Click-chemistry-based perphenylcarbamated beta-CD chiral stationary phase in CEC. Electrophoresis 2009; 30:705-11. [PMID: 19156766 DOI: 10.1002/elps.200800424] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A novel chiral stationary phase (CSP) was prepared by anchoring mono-6-azido-6-deoxyperphenylcarbamated beta-CD onto omega-alkynyl functionalized silica (5 microm) via organic soluble Cu(I)-catalyzed Click chemistry. The obtained CSP was thereafter packed into fused-silica capillary (100 microm id) with an effective length of 9 cm and tested in aqueous CEC to separate a series of racemic aryl alcohols. High separation factors with good resolution were achieved using the current novel CSP. Some pharmaceutical compounds could also be well resolved on this newly derived CSP. The analytical results demonstrate that Click-chemistry-based perphenylcarbamated CSP affords high stability in high electric field and depicts excellent enantioseparation in CEC. The effects of pH value, buffer concentration, applied voltage, concentration of organic modifier and analyte structure on the enantioseparation are also discussed.
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Affiliation(s)
- Yong Wang
- School of Chemical & Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
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45
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Jin J, Hyun MH, Park JH. Chiral separation of amides of amino acid on a (S)-N
-(3,5-dinitrobenzoyl)leucine-N
-phenyl-N
-propylamide-bonded silica using nonaqueous capillary electrochromatography. J Sep Sci 2009; 32:2421-5. [DOI: 10.1002/jssc.200900105] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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46
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Hongjun E, Yang Y, Su P, Zhang W. Preparation of stationary phases for open tubular capillary electrochromatography on the basis of sulfated β-cyclodextrin intercalated in layered double hydroxides. JOURNAL OF ANALYTICAL CHEMISTRY 2009. [DOI: 10.1134/s1061934809040133] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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47
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Trung TQ, Dung PT, Hoan NN, Kim DJ, Lee JH, Kim KH. Chiral separation of fluvastatin enantiomers by capillary electrophoresis. Arch Pharm Res 2008; 31:1066-72. [DOI: 10.1007/s12272-001-1271-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Revised: 08/04/2008] [Accepted: 08/08/2008] [Indexed: 11/29/2022]
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48
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Chiral separation by capillary electromigration techniques. J Chromatogr A 2008; 1204:140-56. [DOI: 10.1016/j.chroma.2008.07.071] [Citation(s) in RCA: 208] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 06/27/2008] [Accepted: 07/08/2008] [Indexed: 11/19/2022]
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49
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D'Orazio G, Fanali S. Enantiomeric separation by using nano-liquid chromatography with on-column focusing. J Sep Sci 2008; 31:2567-71. [DOI: 10.1002/jssc.200800114] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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50
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Preinerstorfer B, Hoffmann C, Lubda D, Lämmerhofer M, Lindner W. Enantioselective silica-based monoliths modified with a novel aminosulfonic acid-derived strong cation exchanger for electrically driven and pressure-driven capillary chromatography. Electrophoresis 2008; 29:1626-37. [DOI: 10.1002/elps.200700525] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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