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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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2
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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: 54] [Impact Index Per Article: 27.0] [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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3
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K S N, Kumar TN, Reddy Singam SS, Chaudhari SR. Selective Homodecoupled 1D- 1H NMR Experiment for Unravelling Enantiomers. Anal Chem 2022; 94:10299-10303. [PMID: 35834712 DOI: 10.1021/acs.analchem.2c01020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1H NMR spectroscopy is a quick and easy tool to resolve enantiomers. However, the paradigm of resolution of enantiomers by 1H NMR is a difficult task due to the minor chemical shift differences and overlap of the resonances of the enantiomers. In the current study, we have performed the conventional selective homodecoupling 1D-1H NMR experiment to achieve chiral resolutions. The predominant features of the proposed methods are (a) high sensitivity as opposed to routinely employed pure shift NMR experiments, (b) easy optimization like conventional 1D-1H NMR, and (c) an artifact-free spectrum. The application of the method has been exhibited in the measurement of proton chemical shift differences between diastereomers and enantiomer excess (ee). The broad use of the proposed method was demonstrated by employing the six samples utilizing the chiral solvating and derivatizing agents.
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Affiliation(s)
- Naresh K S
- Department of Spice and Flavour Science, CSIR - Central Food Technological Research Institute, Mysuru, Karnataka 570020, India.,AcSIR - Academy of Scientific and Innovative Research, Ghaziabad, Uttar Pradesh 201002, India
| | - Theerthan N Kumar
- Department of Spice and Flavour Science, CSIR - Central Food Technological Research Institute, Mysuru, Karnataka 570020, India
| | - Siva Sankara Reddy Singam
- Department of Food Safety and Analytical Quality Control Laboratory, CSIR - Central Food Technological Research Institute, Mysuru, Karnataka 570020, India.,AcSIR - Academy of Scientific and Innovative Research, Ghaziabad, Uttar Pradesh 201002, India
| | - Sachin R Chaudhari
- Department of Spice and Flavour Science, CSIR - Central Food Technological Research Institute, Mysuru, Karnataka 570020, India.,AcSIR - Academy of Scientific and Innovative Research, Ghaziabad, Uttar Pradesh 201002, India
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Complexation of daclatasvir by single isomer methylated β-cyclodextrins studied by capillary electrophoresis, NMR spectroscopy and mass spectrometry. Carbohydr Polym 2021; 273:118486. [PMID: 34560933 DOI: 10.1016/j.carbpol.2021.118486] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/06/2021] [Accepted: 07/22/2021] [Indexed: 11/23/2022]
Abstract
In capillary electrophoresis an enantioseparation of daclatasvir (DCV) was observed in case of heptakis(2,6-di-O-methyl)-β-CD, heptakis(2-O-methyl)-β-CD and β-CD, while two peaks with a plateau were noted for heptakis(2,3,6-tri-O-methyl)-β-CD and heptakis(2,3-di-O-methyl)-β-CD indicating a slow equilibrium. Heptakis(6-O-methyl)-β-CD and heptakis(3-O-methyl)-β-CD yielded broad peaks. Nuclear magnetic resonance experiments including nuclear Overhauser effect-based techniques revealed inclusion complex formation for all CDs with the biphenyl ring of DCV within the cavity and the valine-pyrrolidine moieties protruding from the torus. However, in case of heptakis(2,6-di-O-methyl)-β-CD, heptakis(2-O-methyl)-β-CD and β-CD higher order structures with 1:3 stoichiometry were concluded, where the valine moieties enter additional CD molecules via the secondary side. Heptakis(2,3,6-tri-O-methyl)-β-CD and heptakis(2,3-di-O-methyl)-β-CD yielded primarily 1:1 complexes. Higher order complexes between DCV and heptakis(2,6-di-O-methyl)-β-CD were corroborated by mass spectrometry. Complex stoichiometry was not the reason for the slow equilibrium yielding the plateau observed in capillary electrophoresis, but structural characteristics of the CDs especially complete methylation of the secondary rim.
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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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Li M, Zhang J, Ma S, Jiang Z, Di X, Guo X. Chiral separation of five antihistamine drug enantiomers and enantioselective pharmacokinetic study of carbinoxamine in rat plasma by HPLC-MS/MS. NEW J CHEM 2020. [DOI: 10.1039/d0nj00095g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chiral separation and pharmacokinetic study of antihistamine drugs.
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Affiliation(s)
- Meng Li
- School of Pharmacy
- Shenyang Pharmaceutical University
- Shenyang
- P. R. China
| | - Junyuan Zhang
- School of Pharmacy
- Shenyang Pharmaceutical University
- Shenyang
- P. R. China
| | - Siman Ma
- School of Pharmacy
- Shenyang Pharmaceutical University
- Shenyang
- P. R. China
| | - Zhen Jiang
- School of Pharmacy
- Shenyang Pharmaceutical University
- Shenyang
- P. R. China
| | - Xin Di
- School of Pharmacy
- Shenyang Pharmaceutical University
- Shenyang
- P. R. China
| | - Xingjie Guo
- School of Pharmacy
- Shenyang Pharmaceutical University
- Shenyang
- P. R. China
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Chiu CC, Chen JY, Chen YW, Wang JJ, Hung CH. Subcutaneous brompheniramine for cutaneous analgesia in rats. Eur J Pharmacol 2019; 860:172544. [PMID: 31319069 DOI: 10.1016/j.ejphar.2019.172544] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 07/08/2019] [Accepted: 07/15/2019] [Indexed: 02/07/2023]
Abstract
Brompheniramine as an antihistamine blocked sodium channels, and local anesthetics by blocking sodium channels produced the local anesthetic effects. The authors aimed to assess local anesthetic quality and duration of brompheniramine when compared to the local anesthetic mepivacaine. After rats were shaved and injected subcutaneously on the dorsal skin, the panniculus reflex, induced via applying a noxious pinprick to the skin (injected area), was scored. The dose-response curve and nociceptive block duration of brompheniramine were constructed and compared with mepivacaine. The cutaneous analgesic effects in both brompheniramine and mepivacaine groups were concentration-dependent. On the basis of the amount required to produce a 50% block effect (ED50, 50% effective dose), the drug's potency was brompheniramine (0.89 [0.82-0.96] μmol) better than mepivacaine (2.45 [2.17-2.76] μmol) (P < 0.01). Full recovery time of brompheniramine was more prolonged than mepivacaine's (P < 0.01) on infiltrative cutaneous analgesia when comparing ED25s, ED50s and ED75s. Our preclinical data demonstrated that subcutaneous brompheniramine induces dose-relatedly analgesic effects, and brompheniramine induces prolonged analgesic duration when compared with mepivacaine. Brompheniramine also provokes better cutaneous analgesia than mepivacaine.
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Affiliation(s)
- Chong-Chi Chiu
- Department of General Surgery, Chi-Mei Medical Center, Tainan and Liouying, Taiwan; Department of Electrical Engineering, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Jen-Yin Chen
- Department of Anesthesiology, Chi-Mei Medical Center, Tainan, Taiwan; Department of the Senior Citizen Service Management, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Yu-Wen Chen
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan; Department of Physical Therapy, College of Health Care, China Medical University, Taichung, Taiwan
| | - Jhi-Joung Wang
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan; Allied AI Biomed Center, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Ching-Hsia Hung
- Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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Guo J, Wang J, Lin H, Feng Y, Shen H, Huang R, Liu L, Zhao Z. Combination of capillary electrophoresis and molecular modeling to study the enantiomer affinity pattern between β-blockers and anionic cyclodextrin derivatives in a methanolic and water background electrolyte. J Sep Sci 2019; 42:1077-1087. [PMID: 30659744 DOI: 10.1002/jssc.201800884] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 12/21/2018] [Accepted: 12/22/2018] [Indexed: 12/27/2022]
Abstract
In order to have deep insights into the mechanisms of enantiomer affinity pattern in both aqueous and non-aqueous systems, an approach combining capillary electrophoresis and molecular modeling was undertaken. A chiral β-blocker; acebutolol, was enantioseparated in aqueous capillary electrophoresis and non-aqueous capillary electrophoresis using two anionic β-cyclodextrin derivatives. The enantiomer affinity pattern of acebutolol was found to be opposite when an aqueous background electrolyte was replaced with non-aqueous background electrolyte in the presence of heptakis(2,3-di-O-acetyl-6-sulfo)-β-cyclodextrin but remained the same in the presence of heptakis(2,3-di-O-methyl-6-sulfo)-β-cyclodextrin. Molecular docking of acebutolol into two β-cyclodextrin derivatives indicated two distinct binding modes called 'up' and 'down' conformations. After structure optimization by molecular dynamics and energy minimization, both enantiomers of acebutolol were preferred to the 'up' conformation with heptakis(2,3-di-O-methyl-6-sulfo)-β-cyclodextrin while 'down' conformation with heptakis(2,3-di-O-acetyl-6-sulfo)-β-cyclodextrin. The further calculation of the complex energy with solvent effect indicated that heptakis(2,3-di-O-acetyl-6-sulfo)-β-cyclodextrin had higher affinity to S-acebutolol than R-acebutolol in non-aqueous capillary electrophoresis while it showed better binding to R-acebutolol in aqueous capillary electrophoresis. However, the heptakis(2,3-di-O-methyl-6-sulfo)-β-cyclodextrin bound better to R-acebutolol in both aqueous and non-aqueous capillary electrophoresis, implying that the binding mode played more important role in chiral separation of heptakis(2,3-di-O-methyl-6-sulfo)-β-cyclodextrin while the solvent effect had prevailing impact on heptakis(2,3-di-O-acetyl-6-sulfo)-β-cyclodextrin.
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Affiliation(s)
- Jialiang Guo
- School of Stomatology and Medicine, Foshan University, Foshan, P. R. China
| | - Jincai Wang
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
| | - Hang Lin
- Institute of Pharmaceutical Analysis, College of Pharmacy, Jinan University, Guangzhou, P. R. China
| | - Ying Feng
- Institute of Pharmaceutical Analysis, College of Pharmacy, Jinan University, Guangzhou, P. R. China
| | - Huanqi Shen
- School of Stomatology and Medicine, Foshan University, Foshan, P. R. China
| | - Ruoshi Huang
- School of Stomatology and Medicine, Foshan University, Foshan, P. R. China
| | - Lian Liu
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
| | - Zhixiong Zhao
- School of Stomatology and Medicine, Foshan University, Foshan, P. R. China
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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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12
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Yao Y, Zhao Y, Zhang X, Yu J, Guo X. Determination of brompheniramine enantiomers in rat plasma by cation-selective exhaustive injection and sweeping cyclodextrin modified electrokinetic chromatography method. Electrophoresis 2018; 39:2099-2106. [PMID: 29756294 DOI: 10.1002/elps.201800138] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/19/2018] [Accepted: 04/26/2018] [Indexed: 11/09/2022]
Abstract
A method consisting of cation-selective exhaustive injection and sweeping (CSEI-sweeping) as online preconcentration followed by a cyclodextrin modified electrokinetic chromatography (CDEKC) enantioseparation has been developed for the simultaneous determination of two brompheniramine enantiomers in rat plasma. In this method, analytes were electrokinetically injected at a voltage of 8 kV for 80 s in a fused-silica capillary. Prior to the injection, the capillary was rinsed with 50 mM phosphate buffer of pH 3.5, followed by a plug of a higher conductivity buffer (150 mM phosphate pH 3.5, 20 psi, 6 min) and a plug of water (0.5 psi, 5 s). Separation was carried out applying -20 kV in 50 mM phosphate buffer, pH 3.5, containing 10% v/v ACN and 30 mg/mL sulfated-β-cyclodextrin (S-β-CD). Analytical signals were monitored at 210 nm. The detection sensitivity of brompheniramine enantiomers was enhanced by about 2400-fold compared to the normal injection mode (hydrodynamic injection for 3 s at 0.5 psi, with a BGE of 50 mM phosphate buffer containing 20 mg/mL S-β-CD at pH 3.5), and LLOQ of two enantiomers were both 0.0100 μg/mL. In addition, this method had fairly good repeatability and showed promising capabilities in the application of stereoselective pharmacokinetic investigations for brompheniramine enantiomers in rat.
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Affiliation(s)
- Yaqi Yao
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, P. R. China
| | - Yu Zhao
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, P. R. China
| | - Xue Zhang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, P. R. China
| | - Jia Yu
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, P. R. China
| | - Xingjie Guo
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, P. R. China
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13
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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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14
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Zhang P, Xie X, Tang K, Xu W. Chiral separation of brompheniramine enantiomers by recycling high-speed countercurrent chromatography using carboxymethyl-β-cyclodextrin as a chiral selector. J Sep Sci 2016; 39:2300-6. [DOI: 10.1002/jssc.201501240] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 03/28/2016] [Accepted: 04/02/2016] [Indexed: 01/11/2023]
Affiliation(s)
- Panliang Zhang
- Department of Chemistry and Chemical Engineering; Hunan Institute of Science and Technology; Yueyang P.R. China
| | - Xiaojuan Xie
- Department of Chemistry and Chemical Engineering; Hunan Institute of Science and Technology; Yueyang P.R. China
| | - Kewen Tang
- Department of Chemistry and Chemical Engineering; Hunan Institute of Science and Technology; Yueyang P.R. China
| | - Weifeng Xu
- Department of Chemistry and Chemical Engineering; Hunan Institute of Science and Technology; Yueyang P.R. China
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Simultaneous Chiral Separation of Four H1-Antihistamines by Capillary Zone Electrophoresis Using a Dual Cyclodextrin System. Chromatographia 2015. [DOI: 10.1007/s10337-015-2967-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Rogez-Florent T, Azaroual N, Goossens L, Goossens JF, Danel C. NMR investigation of the complexation and chiral discrimination of pyrazole sulfonamide derivatives with cyclodextrins. Carbohydr Polym 2015; 115:598-604. [DOI: 10.1016/j.carbpol.2014.09.046] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 09/03/2014] [Accepted: 09/09/2014] [Indexed: 10/24/2022]
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17
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Danel C, Azaroual N, Chavaria C, Odou P, Martel B, Vaccher C. Comparative study of the complex forming ability and enantioselectivity of cyclodextrin polymers by CE and 1H NMR. Carbohydr Polym 2013; 92:2282-92. [DOI: 10.1016/j.carbpol.2012.11.095] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 10/25/2012] [Accepted: 11/13/2012] [Indexed: 11/16/2022]
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18
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Samakashvili S, Salgado A, Scriba GK, Chankvetadze B. Comparative Enantioseparation of Ketoprofen with Trimethylated α-, β-, and γ-Cyclodextrins in Capillary Electrophoresis and Study of Related Selector-Selectand Interactions Using Nuclear Magnetic Resonance Spectroscopy. Chirality 2012; 25:79-88. [DOI: 10.1002/chir.22111] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 07/19/2012] [Indexed: 11/06/2022]
Affiliation(s)
- Shorena Samakashvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Antonio Salgado
- Department of Medicinal Chemistry; Centro Nacional de Investigaciones Oncológicas (CNIO); Madrid Spain
| | - Gerhard K.E. Scriba
- Department of Pharmaceutical Chemistry; Friedrich Schiller University Jena; Jena Germany
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
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19
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Zhu H, Wu E, Chen J, Jang YS, Kang W, Choi JK, Lee W, Kang JS. Reverse migration order of sibutramine enantiomers as a function of cyclodextrin concentration in capillary electrophoresis. J Pharm Biomed Anal 2011; 54:1007-12. [DOI: 10.1016/j.jpba.2010.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2010] [Revised: 11/28/2010] [Accepted: 12/02/2010] [Indexed: 11/30/2022]
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20
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Sohajda T, Varga E, Iványi R, Fejős I, Szente L, Noszál B, Béni S. Separation of vinca alkaloid enantiomers by capillary electrophoresis applying cyclodextrin derivatives and characterization of cyclodextrin complexes by nuclear magnetic resonance spectroscopy. J Pharm Biomed Anal 2010; 53:1258-66. [DOI: 10.1016/j.jpba.2010.07.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 07/19/2010] [Accepted: 07/21/2010] [Indexed: 10/19/2022]
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21
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Lämmerhofer M. Chiral recognition by enantioselective liquid chromatography: mechanisms and modern chiral stationary phases. J Chromatogr A 2009; 1217:814-56. [PMID: 19906381 DOI: 10.1016/j.chroma.2009.10.022] [Citation(s) in RCA: 514] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 09/30/2009] [Accepted: 10/07/2009] [Indexed: 11/19/2022]
Abstract
An overview of the state-of-the-art in LC enantiomer separation is presented. This tutorial review is mainly focused on mechanisms of chiral recognition and enantiomer distinction of popular chiral selectors and corresponding chiral stationary phases including discussions of thermodynamics, additivity principle of binding increments, site-selective thermodynamics, extrathermodynamic approaches, methods employed for the investigation of dominating intermolecular interactions and complex structures such as spectroscopic methods (IR, NMR), X-ray diffraction and computational methods. Modern chiral stationary phases are discussed with particular focus on those that are commercially available and broadly used. It is attempted to provide the reader with vivid images of molecular recognition mechanisms of selected chiral selector-selectand pairs on basis of solid-state X-ray crystal structures and simulated computer models, respectively. Such snapshot images illustrated in this communication unfortunately cannot account for the molecular dynamics of the real world, but are supposed to be helpful for the understanding. The exploding number of papers about applications of various chiral stationary phases in numerous fields of enantiomer separations is not covered systematically.
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Affiliation(s)
- Michael Lämmerhofer
- Christian Doppler Laboratory for Molecular Recognition Materials, Department of Analytical Chemistry and Food Chemistry, University of Vienna, Waehringer Strasse 38, A-1090 Vienna, Austria.
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22
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Wang LF. Halogenation effects of pheniramines on the complexation with β-cyclodextrin. J Pharm Biomed Anal 2009; 50:392-6. [DOI: 10.1016/j.jpba.2009.05.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 05/13/2009] [Accepted: 05/22/2009] [Indexed: 11/26/2022]
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23
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Kwaterczak A, Duszczyk K, Bielejewska A. Comparison of chiral separation of basic drugs in capillary electrophoresis and liquid chromatography using neutral and negatively charged cyclodextrins. Anal Chim Acta 2009; 645:98-104. [DOI: 10.1016/j.aca.2009.04.049] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 02/27/2009] [Accepted: 04/29/2009] [Indexed: 10/20/2022]
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24
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Danel C, Azaroual N, Brunel A, Lannoy D, Vermeersch G, Odou P, Vaccher C. Study of the complexation of risperidone and 9-hydroxyrisperidone with cyclodextrin hosts using affinity capillary electrophoresis and 1H NMR spectroscopy. J Chromatogr A 2008; 1215:185-93. [DOI: 10.1016/j.chroma.2008.10.094] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 10/23/2008] [Accepted: 10/27/2008] [Indexed: 11/28/2022]
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25
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Kubačák P, Mikuš P, Valášková I, Havránek E. Chiral Separation of Alkylamine Antihistamines in Pharmaceuticals by Capillary Isotachophoresis with Charged Cyclodextrin. Drug Dev Ind Pharm 2008; 33:1199-204. [DOI: 10.1080/03639040701377565] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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26
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Brun H, Paul M, Razzouq N, Binhas M, Gibaud S, Astier A. Cyclodextrin Inclusion Complexes of the Central Analgesic Drug Nefopam. Drug Dev Ind Pharm 2008; 32:1123-34. [PMID: 17090434 DOI: 10.1080/03639040600920663] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Inclusion complexes of nefopam base (NEF) with various beta-cyclodextrins (betaCDs) were investigated. All tested betaCDs increased the apparent solubility of NEF according to a Higuchi AL type plot (except betaCD: AN type plot), which indicates the formation of 1:1 stoichiometry inclusion complexes. 1H-NMR and 13C-NMR experiments showed that complexation by CDs allowed an easy separation of the R and S enantiomers. Based on spectral data obtained from the two-dimensional rotating frame nuclear Overhauser effect spectroscopy (2D-ROESY), a reasonable geometry for the complexes could be proposed implicating the insertion of the benzoxazocine ring into the wide end of the torus cavity.
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Affiliation(s)
- H Brun
- Laboratoire de Pharmacotechnie, Service de Pharmacie, Hôpital Henri Mondor, Créteil, France
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27
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Cruz JR, Becker BA, Morris KF, Larive CK. NMR characterization of the host-guest inclusion complex between beta-cyclodextrin and doxepin. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2008; 46:838-845. [PMID: 18615634 DOI: 10.1002/mrc.2267] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The interaction between doxepin, a member of the tricyclic antidepressant (TCA) class of drugs, with beta-cyclodextrin (beta-CD) was investigated using NMR. Several TCAs have been reported to form a complex with beta-CD having 1:1 stoichiometry. Previous results from UV-visible spectroscopy, fluorescence measurements, and molecular modeling indicated that for imipramine, desipramine, and amitriptyline, the TCA aliphatic tail is included in the cyclodextrin cavity with apparently no interaction of the tricyclic ring. An alternative view of the doxepin-beta-CD complex is presented in this work using analysis of complexation-induced chemical shifts (CICSs), the method of continuous variation (Job's analysis), and analysis of ROESY spectra. The Job's plot derived from the NMR spectral data confirms that the complex formed has 1:1 stoichiometry. The largest changes in the CICS data were observed for the aromatic protons of one of the doxepin rings, with much smaller chemical shift changes observed for the protons of the other aromatic ring and the doxepin tail. Perhaps the most significant evidence for inclusion of the doxepin tricyclic ring is the strong ROESY cross peaks between the doxepin aromatic resonances and the protons located inside the beta-CD cavity. Changes in the doxepin (1)H NMR spectrum and the behavior of ROESY exchange cross peaks suggest that inclusion complex formation decreases the rate of internal motions of doxepin.
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Affiliation(s)
- Jennifer R Cruz
- Department of Chemistry, University of California, Riverside, CA 92521, USA
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28
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Parker KM, Stalcup AM. Affinity capillary electrophoresis and isothermal titration calorimetry for the determination of fatty acid binding with beta-cyclodextrin. J Chromatogr A 2008; 1204:171-82. [DOI: 10.1016/j.chroma.2008.02.050] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Revised: 02/01/2008] [Accepted: 02/05/2008] [Indexed: 10/22/2022]
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29
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Ali I, Gupta VK, Aboul-Enein HY. Chiral Resolution of Racemic Environmental Pollutants by Capillary Electrophoresis. Crit Rev Anal Chem 2008; 38:132-46. [DOI: 10.1080/10408340701804467] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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30
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Marák J, Mikus P, Maráková K, Kaniansky D, Valásková I, Havránek E. Potentialities of ITP-CZE method with diode array detection for enantiomeric purity control of dexbrompheniramine in pharmaceuticals. J Pharm Biomed Anal 2008; 46:870-6. [PMID: 17618074 DOI: 10.1016/j.jpba.2007.05.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Revised: 04/19/2007] [Accepted: 05/19/2007] [Indexed: 11/19/2022]
Abstract
The present work illustrates potentialities of on-line combined isotachophoresis-capillary zone electrophoresis (ITP-CZE) separation techniques coupled with on-capillary diode array detector (DAD) for enantiomeric purity testing of drugs in pharmaceuticals. The general advantages of the proposed method are its (i) high selectivity, (ii) low concentration limit of detection (LOD) obtainable, (iii) enhanced sample loadability, and (iv) enhanced reliability. For separation of brompheniramine (BP) enantiomers, serving as model analytes, carboxyethyl-beta-cyclodextrin (CE-beta-CD) was appropriate chiral selector providing complete enantioresolution. Given by a high sample load capacity (30 microl sample injection volume) and preconcentration of the analytes in ITP stage, concentration LOD of levobrompheniramine (LBP), serving as model impurity, was 2.5 ng/ml (8 x 10(-9)mol/l). Such separation and detection conditions enabled to easily determine LBP in samples containing a 10(3) excess of dexbrompheniramine (DBP). DAD detection in comparison with single wavelength detection can enhance value of analytical information when analytes and interferents have different spectra (distinguishing impurities in analyte zone, confirmation of migration positions of migrants). In this context purity of BP zones was confirmed with higher reliability in pharmaceutical sample. Moreover, distinguishing the trace analyte signal superposed on the baseline noise was provided with sufficient reliability (for this purpose the background correction and smoothing procedure had to be applied to the raw DAD spectra). Successful validation and application of the proposed ITP-CZE-DAD method suggest its routine use for the enantiomeric purity testing of pharmaceuticals.
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Affiliation(s)
- Jozef Marák
- Department of Analytical Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská Dolina CH-2, SK-842 15 Bratislava, Slovak Republic
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31
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Bicker W, Chiorescu I, Arion VB, Lämmerhofer M, Lindner W. Contributions to chromatographic chiral recognition of permethrinic acid stereoisomers by a quinine carbamate chiral selector: evidence from X-ray diffraction, DFT computations, 1H NMR, and thermodynamic studies. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.tetasy.2007.11.037] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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32
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Mikus P, Maráková K, Marák J, Kaniansky D, Valásková I, Havránek E. Possibilities of column coupling electrophoresis provided with a fiber-based diode array detection in enantioselective analysis of drugs in pharmaceutical and clinical samples. J Chromatogr A 2008; 1179:9-16. [PMID: 17905259 DOI: 10.1016/j.chroma.2007.09.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Revised: 08/30/2007] [Accepted: 09/03/2007] [Indexed: 11/20/2022]
Abstract
The present work illustrated possibilities of column coupling electrophoresis combined with ionizable chiral selector and diode array detection (DAD) for the enantioselective analysis of trace drugs (pheniramine and its analogs) in pharmaceutical and clinical samples. Isotachophoresis (ITP), on-line coupled with capillary zone electrophoresis (CZE), served as an ideal injection technique (high sample load capacity, narrow and sharp drugs zones) of on-line pretreated samples (preseparation, purification and preconcentration of drugs) for the CZE stage. Enhanced (enantio)separation selectivity of CZE with ionizable chiral selector (carboxyethyl-beta-cyclodextrin recognized between drugs enantiomers on one hand as well as between drugs and sample matrix constituents on the other hand) enabled to obtain pure zones of the drugs enantiomers, suitable for their detection and quantitation. DAD in comparison with single wavelength UV detection enhanced value of analytical information verifying purity of drugs enantiomers zones (indicating interferents with different spectra to those of drugs). Obtained results indicated pure zones of interest confirming effective ITP-CZE (enantio)separation process. Distinguishing the trace analytes signals superposed on the baseline noise was provided with sufficient reliability (for this purpose the background correction and smoothing procedure had to be applied to the raw DAD spectra). The proposed ITP-CZE-DAD methods were characterized by favorable performance parameters (sensitivity, linearity, precision, recovery, accuracy, robustness, selectivity) and successfully applied for (i) enantiomeric purity testing of dexbrompheniramine in commercial pharmaceutical tablets and (ii) enantioselective metabolic study of pheniramine in human urine.
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Affiliation(s)
- Peter Mikus
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University, Odbojárov 10, Bratislava, Slovak Republic.
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33
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Shpigun OA, Ananieva IA, Budanova NY, Shapovalova EN. Use of cyclodextrins for separation of enantiomers. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc2003v072n12abeh000817] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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34
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Martínez-Gómez MA, Sagrado S, Villanueva-Camañas RM, Medina-Hernández MJ. Enantiomeric quality control of antihistamines in pharmaceuticals by affinity electrokinetic chromatography with human serum albumin as chiral selector. Anal Chim Acta 2007; 592:202-9. [PMID: 17512827 DOI: 10.1016/j.aca.2007.04.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Revised: 04/04/2007] [Accepted: 04/16/2007] [Indexed: 10/23/2022]
Abstract
The present paper deals with the enantiomeric separation of six antihistaminic enantiomers by affinity electrokinetic chromatography (AEKC)-partial filling technique using human serum albumin (HSA) as chiral selector. A multivariate optimization approach of the most critical experimental variables in enantioresolution, running pH, HSA concentration and HSA plug length (SPL) was carried out since there are interactions between variables that could not be considered in an univariate optimization. The estimated and experimental resolution values obtained for antihistaminic enantiomers varied from 1.13 (for orphenadrine) to 2.15 (for brompheniramine). The optimum experimental conditions for enantioresolution of each compound were: brompheniramine, pH 8.5, [HSA] 180 microM, SPL 180 s; chlorcyclizine, pH 6.5, [HSA] 180 microM, SPL 150 s; chlorpheniramine, pH 8.25, [HSA] 160 microM, SPL 150 s; hydroxyzine, pH 7.0, [HSA] 180 microM, SPL 150 s; and orphenadrine, pH 7.8, [HSA] 160 microM, SPL 150 s. pH and the quadratic term of pH seem to be the most critical factors that determine enantioresolution of antihistamines. The validity of the developed methodologies to enantiomeric quality control of antihistamines in pharmaceutical formulations is demonstrated analyzing the content of brompheniramine, chlorpheniramine and hyroxyzine enantiomers in commercially available pharmaceutical formulations containing racemic mixtures of compounds. Resolution, accuracy, reproducibility, cost and sample throughput of the proposed methodologies make them suitable for quality control of the enantiomeric composition of antihistamines in pharmaceutical preparations.
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Affiliation(s)
- M A Martínez-Gómez
- Departamento de Química Analítica, Facultat de Farmacia, Universitat de València, C/Vicent Andrés Estellés s/n, E-46100 Burjassot, Valencia, Spain
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35
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Higashiyama M, Inada K, Ohtori A, Kakehi K. NMR analysis of ion pair formation between timolol and sorbic acid in ophthalmic preparations. J Pharm Biomed Anal 2006; 43:1335-42. [PMID: 17145156 DOI: 10.1016/j.jpba.2006.10.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2006] [Revised: 10/27/2006] [Accepted: 10/29/2006] [Indexed: 10/23/2022]
Abstract
Ion pair formation between timolol and sorbic acid was investigated using NMR spectroscopy in order to clarify their interactions within ophthalmic preparation. (13)C and (1)H NMR spectra of timolol, sorbic acid, and a mixture of the two were obtained, and the signal changes induced by pairing were observed. The carbon signals of the butylaminopropanol moiety of timolol were markedly shifted in the mixture, as were the carboxyl and conjugated carbons assigned to sorbic acid. The localizations of the changes in each molecule revealed the binding sites. The profiles of butylaminopropanol carbon chemical shifts plotted against a molar ratio of sorbate were synchronized, which suggested a single type of interaction with sorbic acid. The Job plot showed a typical pattern with a single-maximum at a mole function of 0.5, indicating the presence of a 1:1 complex of timolol and sorbic acid. The stability constants (K) of the timolol-sorbate and timolol-maleate pairs were 1.9x10(1) and 2.2x10(2)M(-1), respectively. The higher K value of the timolol-maleate interaction suggested that it was dominant to the timolol-sorbate interaction when maleate and sorbate coexisted within a timolol solution. Here, we demonstrated evidence of an interaction between timolol and sorbic acid using simple NMR measurements, which suggested the existence of ion pair formation derived from charge neutralization. Our analysis using NMR spectroscopy should advance the understanding and optimization of formulations that are based on ion pair.
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Affiliation(s)
- Masayo Higashiyama
- Senju Pharmaceutical Co. Ltd., 1-5-4 Murotani, Nishi-Ku, Kobe 651-2241, Japan.
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36
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Lausecker B, Fischer G. Determination of the enantiomeric composition of a new insulin sensitizer in plasma samples from non-clinical and clinical investigations using chiral HPLC with electrospray tandem mass spectrometric detection. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 835:40-6. [PMID: 16567137 DOI: 10.1016/j.jchromb.2006.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Revised: 01/09/2006] [Accepted: 03/05/2006] [Indexed: 10/24/2022]
Abstract
Two drug assays were developed and applied to assess the enantiomeric composition of an insulin sensitizer drug in plasma after administration of its racemate to man, and in human and animal plasma and serum samples generated after in vitro experiments. The sample preparation for the assays consisted either of protein precipitation and column-switching, or liquid-liquid extraction and direct injection. Subsequently, both assays employed chiral HPLC coupled to atmospheric pressure ionization mass spectrometry. An interconversion of the racemate to a mixture enriched with the (+)-enantiomer could be confirmed for all species and biological matrices. The individual enantiomers could be quantified in the concentration range 0.5-500 ng/ml, starting with a 100-microl plasma aliquot. Inter- and intra-assay precision and accuracy were in the range 0.1-7.9 and 88.8-106.0%, respectively. Run times of 5 min for a single sample allows the analysis of more than 200 samples overnight.
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Affiliation(s)
- B Lausecker
- F. Hoffmann-La Roche Ltd., Pharmaceuticals Division, Non-Clinical Drug Safety, P.O. Box, CH-4070 Basel, Switzerland.
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37
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Capella-Peiró ME, Bossi A, Esteve-Romero J. Optimization by factorial design of a capillary zone electrophoresis method for the simultaneous separation of antihistamines. Anal Biochem 2006; 352:41-9. [PMID: 16549055 DOI: 10.1016/j.ab.2005.12.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Revised: 12/13/2005] [Accepted: 12/15/2005] [Indexed: 10/25/2022]
Abstract
A 3(2) full factorial design was used to optimize the experimental conditions of a capillary zone electrophoresis method aimed at achieving simultaneous separation and quantification of the antihistamines brompheniramine, chlorpheniramine, cyproheptadine, diphenhydramine, doxylamine, hydroxyzine, and loratadine according to their therapeutic group. A statistical program, SPSS, was used to calculate the mathematical model with which to obtain the response surface. Critical parameters such as pH and applied voltage were studied to evaluate their effect on resolution and on efficiency. Optimum separation conditions were phosphate buffer pH 2.0, 5kV, and 2psis(-1) at 214nm. The analysis time was below 9min and the theoretical plates were between 6000 and 63,000N. Calibration curves were prepared for the antihistamines. The limits of detection were 4-14ngmL(-1), which allow their quantification in pharmaceuticals. The RSD% of each antihistamine was fairly good. Up to seven antihistamines belonging to the antihistaminic H(1)-receptor group were separated in the same electropherogram. The proposed method was then applied to the determination of antihistamines in pharmaceutical, urine, and serum samples with recoveries in agreement with the stated contents.
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Affiliation(s)
- M Elisa Capella-Peiró
- Dipartimento Scientifico e Tecnologico, Università degli Studi di Verona, Strada Le Grazie 15, 37134 Verona, Italy.
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38
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Ali I, Kumerer K, Aboul-Enein HY. Mechanistic Principles in Chiral Separations Using Liquid Chromatography and Capillary Electrophoresis. Chromatographia 2006. [DOI: 10.1365/s10337-006-0762-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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39
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Dignam CF, Randall LA, Blacken RD, Cunningham PR, Lester SKG, Brown MJ, French SC, Aniagyei SE, Wenzel TJ. Carboxymethylated cyclodextrin derivatives as chiral NMR discriminating agents. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2006.04.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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40
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Danel C, Azaroual N, Foulon C, Goossens JF, Vermeersch G, Bonte JP, Vaccher C. NMR studies of chiral recognition mechanisms: interaction of enantiomers of N-imidazole derivatives with cyclodextrin hosts. Correlation with the CD-EKC studies. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2006.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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41
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Mikus P, Valásková I, Havránek E. Enantioselective determination of pheniramine in pharmaceuticals by capillary electrophoresis with charged cyclodextrin. J Pharm Biomed Anal 2005; 38:442-8. [PMID: 15925245 DOI: 10.1016/j.jpba.2005.01.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2004] [Revised: 01/21/2005] [Accepted: 01/25/2005] [Indexed: 11/23/2022]
Abstract
Cyclodextrin (CD)-mediated capillary zone electrophoresis (CZE) in hydrodynamically closed separation system was developed for the separation and quantitation of pheniramine (PHM) enantiomers. Several parameters affecting the separation were studied, including the type and concentration of chiral selector, carrier cation and counterion, and the pH of the buffer. A high effectivity of oppositely migrating carboxyethyl-beta-cyclodextrin (CE-beta-CD) to separate the PHM enantiomers was demonstrated in detail. The optimized chiral analysis of the antihistamine drug was performed in a buffer consisted of 20 mmol/l epsilon-aminocaproic acid adjusted to pH 4.5 with acetic acid, containing negatively charged CE-beta-CD (2.5 mg/ml) as chiral selector and 0.2% (w/v) methylhydroxyethylcellulose (m-HEC) as an electro-osmotic flow (EOF) suppressor. Acceptable validation criteria for sensitivity, linearity, precision, accuracy/recovery were included. The proposed CZE method was successfully applied to the assay of PHM in pharmaceutical formulations using dioxopromethazine as an internal standard.
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Affiliation(s)
- Peter Mikus
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University, Odbojárov 10, SK-83232 Bratislava, Slovak Republic.
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42
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Liu Q, Viranga Tillekeratne LM, Kim YW, Kirchhoff JR, Hudson RA. Evaluation of chiral discrimination of highly negatively charged enantiomers by quaternary ammonium β-cyclodextrin using1H NMR. Chirality 2005; 17:570-6. [PMID: 16196023 DOI: 10.1002/chir.20209] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The positively charged quaternary ammonium cyclodextrin, QA-beta-CD, was previously used as a chiral selector to achieve baseline resolution of two of the dianionic enantiomers of disodium 3-(p-isothiocyanatophenoxy)-3-(p-isothiocyanatophenyl)propane-1,2-disulfate by capillary electrophoresis. The basis of the chiral discrimination between QA-beta-CD and the enantiomers was investigated by (1)H NMR spectroscopy. COSY and NOESY spectra were used to infer the role that molecular interactions and the stereocenters have upon association of QA-beta-CD with the enantiomers. A parallel two-step complexation model is used to rationalize the NMR and the chiral discrimination observed during separation of the enantiomers.
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Affiliation(s)
- Qinfeng Liu
- Department of Chemistry, College of Arts & Sciences, University of Toledo, Ohio 43606, USA
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43
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Abstract
Chiral recognition by cyclodextrins is of considerable importance, especially for pharmaceutical industry, in view of the possible side effects of the second enantiometer of chiral drugs. In general, it manifests itself in all NMR parameters (chemical shifts, coupling constants, NOE and ROE effects, and relaxation rates) on one hand. On the other hand, it allows one to determine the thermodynamic parameters characterizing diastereomeric complexes formed by cyclodextrins with enantiomeric guests. After an introduction and a general discussion of NMR manifestations of chiral recognition by cyclodextrin, the existing literature data on this problem will be discussed herein. Chirality 16:90-105, 2004.
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Affiliation(s)
- Helena Dodziuk
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland.
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44
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Chankvetadze B, Burjanadze N, Maynard DM, Bergander K, Bergenthal D, Blaschke G. Comparative enantioseparations with native beta-cyclodextrin and heptakis-(2-O-methyl- 3,6-di-O-sulfo)-beta-cyclodextrin in capillary electrophoresis. Electrophoresis 2002; 23:3027-34. [PMID: 12207312 DOI: 10.1002/1522-2683(200209)23:17<3027::aid-elps3027>3.0.co;2-v] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Twenty-three cationic chiral analytes were resolved in capillary electrophoresis using native beta-cyclodextrin and single isomer heptakis-(2-O-methyl-3,6-di-O-sulfo)-beta-cyclodextrin as chiral selectors. For 12 of 16 chiral analytes resolved with both chiral selectors the enantiomer migration order was opposite. In selected cases the structure of cyclodextrin-analyte complexes in aqueous solution was investigated using one-dimensional transverse rotating frame nuclear Overhauser and exchange spectroscopy. It was found that in contrast to mainly inclusion-type complexes between chiral analytes and beta-cyclodextrin, external complexes are formed between the chiral analytes and structurally crowded, highly charged heptakis-(2-O-methyl-3,6-di-O-sulfo)-beta-cyclodextrin.
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Affiliation(s)
- Bezhan Chankvetadze
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Münster, Germany.
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45
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Tárkányi G. Quantitative approach for the screening of cyclodextrins by nuclear magnetic resonance spectroscopy in support of chiral separations in liquid chromatography and capillary electrophoresis enantioseparation of norgestrel with alpha-, beta- and gamma-cyclodextrins. J Chromatogr A 2002; 961:257-76. [PMID: 12184623 DOI: 10.1016/s0021-9673(02)00429-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A quantitative NMR approach is proposed for the screening of cyclodextrins with regard to their enantioselectivity as chiral mobile phase additives in column reversed-phase chromatography and capillary electrophoresis. Similarities and differences between the mechanism of enantiomeric peak-separation in NMR and HPLC and CE are interpreted. The affinity of d-norgestrel to bind to (alpha-, beta-, gammay-) cyclodextrins in aqueous solution was quantified and compared by determining the association constants from chemical shift data. The association constant of l-norgestrel was estimated from titration of the racemate. Differences between the apparent association constants of the enantiomerically pure drug and the racemate are discussed from the point of view of enantiomeric competition for the cyclodextrin. The apparent association constants and chiral selectivities determined by 'H NMR for dl-norgestrell/gamma-CD system at various water-methanol ratios are correlated with the corresponding chromatographic results found in the literature. The pitfalls of previously proposed screening methods based on comparison of chemical shift differences with separation parameters are discussed.
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Affiliation(s)
- Gábor Tárkányi
- Spectroscopic Research Division, Gedeon Richter Ltd, Budapest, Hungary.
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46
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Scriba GKE. Selected fundamental aspects of chiral electromigration techniques and their application to pharmaceutical and biomedical analysis. J Pharm Biomed Anal 2002; 27:373-99. [PMID: 11755740 DOI: 10.1016/s0731-7085(01)00653-7] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
While capillary electrophoresis has been established as a major enantioseparation technique within the last decade, the potential of capillary electrochromatography is still studied extensively. This review summarizes recent applications of electromigration techniques with regard to the enantioseparation of chiral drugs. The first part discusses the general aspects of migration models and the enantiomer migration order. The application of capillary electrophoresis to chiral pharmaceutical analysis considers recent literature on: (1) chiral resolutions of non-racemic mixtures of enantiomers for the development of assays and the determination of the stereochemical purity of the drugs, (2) chiral separations of compounds in pharmaceutical formulations and products, and (3) enantioseparations of drugs in biological samples. A shorter section devoted to chiral electrochromatography discusses some fundamental aspects as well as the application to the chiral analysis of drugs including bioanalysis.
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Affiliation(s)
- Gerhard K E Scriba
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of Jena, Philosophenweg 14, D-07743 Jena, Germany.
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47
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Wedig M, Laug S, Christians T, Thunhorst M, Holzgrabe U. Do we know the mechanism of chiral recognition between cyclodextrins and analytes? J Pharm Biomed Anal 2002; 27:531-40. [PMID: 11755754 DOI: 10.1016/s0731-7085(01)00579-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The resolution of chiral phenethylamine analogue compounds were studied in presence of single-isomer neutral and negatively charged cyclodextrins (CDs) by means of capillary electrophoresis (CE) and NMR spectroscopy. Whereas the native beta-CD and heptakis(2-N,N-dimethylcarbamoyl)beta-cyclodextrin were not able to separate the racemates of four ephedrine derivatives studied, heptakis(2,3-O-diacetyl)beta-cyclodextrin and especially heptakis(2,3-O-diacetyl-6-sulfo)beta-cyclodextrin could resolve all four pairs of enantiomers in one run. UV and NMR spectroscopic measurements revealed various kinds of complexes of phenethylamines with the CDs. Either defined inclusion complexes or manifold complexes which are mostly characterized by an attachment of the analyte to the outside of the CD cavity were found. No correlation between the kind of complexation and the resolution observed by means of CE could be found.
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Affiliation(s)
- M Wedig
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, D-97074 Wurzburg, Germany
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48
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Amini A. Recent developments in chiral capillary electrophoresis and applications of this technique to pharmaceutical and biomedical analysis. Electrophoresis 2001; 22:3107-30. [PMID: 11589272 DOI: 10.1002/1522-2683(200109)22:15<3107::aid-elps3107>3.0.co;2-z] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
This paper provides an overview of the current status of chiral capillary electrophoresis (CE). The emphasis is placed on the application of CE in chiral separation of various racemic compounds. During the last two years about 280 papers, several review articles, and two entire issues, edited by S. Fanali (Electrophoresis 1999, 20, 2577-2798, and H. Nishi and S. Terabe (J. Chromatogr. A 2000, 879, 1-471.) have been devoted to chiral CE. Enantiomeric separations of various compounds, e.g., pharmaceuticals, drug candidates, drugs and related metabolites in biological fluids, amino acids, di- and tri peptides, pesticides and fungicides, have been performed using different chiral selectors. Native and derivatized cyclodextrins continue to be the most widely used chiral selectors. Other chiral selectors such as natural and synthetic chiral micelles, crown ethers, chiral ligands, proteins, oligo- and polysaccharides, and macrocyclic antibiotics have also been applied to chiral CE separations.
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Affiliation(s)
- A Amini
- Medical Product Agency, Division of Biotechnology, Uppsala, Sweden.
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49
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Chankvetadze B, Lomsadze K, Bergenthal D, Breitkreutz J, Bergander K, Blaschke G. Mechanistic study on the opposite migration order of clenbuterol enantiomers in capillary electrophoresis with beta-cyclodextrin and single-isomer heptakis(2,3-diacetyl-6-sulfo)-beta-cyclodextrin. Electrophoresis 2001; 22:3178-84. [PMID: 11589277 DOI: 10.1002/1522-2683(200109)22:15<3178::aid-elps3178>3.0.co;2-f] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Opposite migration order was observed for the enantiomers of the chiral beta2-adrenergic drug clenbuterol (CL) in capillary electrophoresis (CE) when resolved with native beta-cyclodextrin (beta-CD) and heptakis (2,3-diacetyl-6-sulfo)-beta-CD (HDAS-beta-CD). The possible mechanisms of the affinity reversal of the CL enantiomers depending on the structure of the CD were studied using 1H-nuclear magnetic resonance (1H-NMR) spectrometry and one-dimensional rotating frame nuclear Overhauser and exchange spectrometry (1-D ROESY). Significant differences were observed between the structure of the (+/-)-CL complexes with beta-CD and HDAS-beta-CD.
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Affiliation(s)
- B Chankvetadze
- Institute of Pharmaceutical Chemistry, University of Münster, Germany
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50
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Chankvetadze B, Burjanadze N, Blaschke G. Enantioseparation of the anticoagulant drug phenprocoumon in capillary electrophoresis with UV and laser-induced fluorescence detection and application of the method to urine samples. Electrophoresis 2001; 22:3281-5. [PMID: 11589291 DOI: 10.1002/1522-2683(200109)22:15<3281::aid-elps3281>3.0.co;2-c] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The enantioseparation of phenprocoumon (PhC) in capillary electrophoresis (CE) has been studied using various cyclodextrins (CDs) such as native alpha, beta and gamma-CD and several neutral and randomly, as well as selectively substituted charged CD derivatives. Reversal of the enantiomer migration order was observed when using heptakis(2,3,6-tri-O-methyl (TM)-beta-CD as a chiral selector compared to all other CDs used. The detection of PhC was performed using either UV or laser-induced fluorescence (LIF) detection. The limit of detection (LOD) observed with LIF detection was ca. 20 times lower compared to UV. The method has been applied to the analysis of urine samples of the patient under treatment with PhC in combination with other drugs such as ramipril, hydrochlorothiazide, and nifedipine.
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Affiliation(s)
- B Chankvetadze
- Institute of Pharmaceutical Chemistry, University of Münster, Germany
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