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J SJS, Handlovic TT, Wahab MF, Armstrong DW. Enhancing enantiomeric and diastereomeric separations: A single chromatograph approach for two-dimensional heart-cut methodology. Talanta 2024; 267:125243. [PMID: 37778183 DOI: 10.1016/j.talanta.2023.125243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 10/03/2023]
Abstract
A high-performance chromatograph was adapted and reconfigured to establish a two-dimensional methodology for separations that are not easily achievable using a single enantioselective column. Allethrin, a pyrethroid used widely as a pesticide in domestic environments, was chosen as the model analyte. With three chiral centers, it has eight stereoisomers and is considered one of the more difficult chiral separations. Diastereomeric separation was achieved in the first dimension using a shape-selective stationary phase based on ultrapure porous graphitic carbon (particle diameter, 3 μm) in the reversed phase mode. Advanced asymmetric bidirectional peak functions (half-Gaussian modified Gaussian and exponentially modified Gaussian) were employed to extract overlapping peak areas. The four diastereomeric peaks were heart-cut and sent to the second dimension online using a standard six-port 2-position rotary valve. Enantiomeric separation was attained in the second dimension using an immobilized-cellulose tris(3,5-dichlorophenylcarbamate) column (3 μm) with chromatographic resolutions >2.7 for all enantiomeric pairs. The second dimension method was developed using the information from circular dichroism detection. The baseline separation of seven peaks of allethrin in a single dimension was also demonstrated using (2-hydroxypropyl)-β-cyclodextrin. The enantiomeric purity of a purified formulation of allethrin in a commercial pesticide was validated using the developed 2D approach.
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Affiliation(s)
| | - Troy T Handlovic
- Department of Chemistry and Biochemistry, University of Texas at Arlington, 76019, USA
| | - M Farooq Wahab
- Department of Chemistry and Biochemistry, University of Texas at Arlington, 76019, USA
| | - Daniel W Armstrong
- Department of Chemistry and Biochemistry, University of Texas at Arlington, 76019, USA.
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2
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Elbashir AA, Aboul-Enein HY. Multidimensional Gas Chromatography for Chiral Analysis. Crit Rev Anal Chem 2018; 48:416-427. [DOI: 10.1080/10408347.2018.1444465] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
| | - Hassan Y. Aboul-Enein
- Pharmaceutical and Medicinal Chemistry Department, Division of Pharmaceutical and Drug Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
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3
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Guo F, Tang Q, Xie J, Zhao L, Liu K, Liu W. Enantioseparation and identification for the rationalization of the environmental impact of 4 polychlorinated biphenyls. Chirality 2018; 30:475-483. [PMID: 29315818 DOI: 10.1002/chir.22811] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/12/2017] [Accepted: 07/18/2017] [Indexed: 12/29/2022]
Abstract
Polychlorinated biphenyls (PCBs) are harmful and persistent organic pollutants that have long been used in industrial manufacturing. Their persistence leads to accumulation in the food chain causing potential toxic effects. As 19 out of 78 of the chiral congeners have stable atropisomers at ambient temperature, we studied some typical enantiomers: PCB45, PCB95, PCB136, and PCB149. The chiral stationary phases OD-H and OJ-H were used for separation in analytic high-performance liquid chromatography (HPLC), as well as for collection in semi-preparative HPLC. The resolution was optimized with respect to n-hexane-based mobile phases, temperature, and flow rate. All pure enantiomers were recovered from semi-preparative HPLC within 15 minutes for practical purpose. Characterization of the absolute configurations were conducted with a combination of theoretical and experimental electronic circular dichroism measurements. The enantiomers of PCB45, PCB95, PCB136, and PCB149 proved to be eluted as R > S, S > R, R > S, and S > R, respectively. Molecular structures (eg, substituent groups) and properties (eg, bond lengths, bond angles, and dipole moments) were quantitatively analyzed to understand the toxicity effect of PCBs. In summary, we have developed a well-established methodology of collection and configuration identification for analogous PCB derivatives.
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Affiliation(s)
- Fangjie Guo
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Qiaozhi Tang
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Jingqian Xie
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Lu Zhao
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Kai Liu
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California
| | - Weiping Liu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang Province, China
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Vetter W. Gas Chromatographic Enantiomer Separation of Polychlorinated Biphenyls (PCBs): Methods, Metabolisms, Enantiomeric Composition in Environmental Samples and their Interpretation. Isr J Chem 2016. [DOI: 10.1002/ijch.201600089] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Walter Vetter
- University of Hohenheim; Institute of Food Chemistry; Garbenstr. 28 D-70593 Stuttgart Germany
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Badea SL, Danet AF. Enantioselective stable isotope analysis (ESIA) - a new concept to evaluate the environmental fate of chiral organic contaminants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 514:459-466. [PMID: 25687672 DOI: 10.1016/j.scitotenv.2015.01.082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/26/2015] [Accepted: 01/26/2015] [Indexed: 06/04/2023]
Abstract
Since 2011, the enantiospecific stable carbon isotope analysis (ESIA) has emerged as an innovative technique to assess the environmental fate of chiral emerging compounds by combining in one experimental technique both compound specific isotope analysis (CSIA) and enantioselective analysis. To date, the ESIA was applied for four classes of compounds: α-hexachlorocyclohexane (α-HCH), polar herbicides (phenoxy acids), synthetic polycyclic musk galaxolide (HHCB), and phenoxyalkanoic methyl herbicides. From an analytical point of view there are factors that are hindering the application of ESIA methods for the field samples: (i.e. amounts of target analyte, matrix effects, GC resolution) and overcoming these factors is challenging. While ESIA was shown as a mature technique for the first three abovementioned class of compounds, no isotope analysis of individual enantiomers could be performed for phenoxyalkanoic methyl herbicides. With respect to field studies, one study showed that ESIA might be a promising tool to distinguish between biotic and abiotic transformation pathways of chiral organic contaminants and even to differentiate between their aerobic and anaerobic biotransformation pathways. The development of ESIA methods for new chiral emerging contaminants in combination with development of multi-element isotope analysis will contribute to a better characterization of transformation pathways of chiral organic contaminants.
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Affiliation(s)
| | - Andrei-Florin Danet
- Department of Analytical Chemistry, University of Bucharest, Faculty of Chemistry, 90-92 Panduri Str., Bucharest 050657, Romania
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6
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West C, Cieslikiewicz-Bouet M, Lewinski K, Gillaizeau I. Enantiomeric Separation of Original Heterocyclic Organophosphorus Compounds in Supercritical Fluid Chromatography. Chirality 2013; 25:230-7. [DOI: 10.1002/chir.22133] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 10/15/2012] [Indexed: 11/06/2022]
Affiliation(s)
- Caroline West
- Institut de Chimie Organique et Analytique (ICOA); Université d'Orléans, UMR CNRS 7311; B.P. 6759, rue de Chartres 45067 Orléans Cedex 2 France
| | - Monika Cieslikiewicz-Bouet
- Institut de Chimie Organique et Analytique (ICOA); Université d'Orléans, UMR CNRS 7311; B.P. 6759, rue de Chartres 45067 Orléans Cedex 2 France
- Department of Organic Chemistry; Jagiellonian University; R. Ingardena 3 30060 Krakow Poland
| | - Krzysztof Lewinski
- Department of Organic Chemistry; Jagiellonian University; R. Ingardena 3 30060 Krakow Poland
| | - Isabelle Gillaizeau
- Institut de Chimie Organique et Analytique (ICOA); Université d'Orléans, UMR CNRS 7311; B.P. 6759, rue de Chartres 45067 Orléans Cedex 2 France
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7
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Zhang A, Gao W, Ma B, Jin L, Lin C. Enantiomeric separations of chiral polychlorinated biphenyls on three polysaccharide-type chiral stationary phases by supercritical fluid chromatography. Anal Bioanal Chem 2012; 403:2665-72. [DOI: 10.1007/s00216-012-6063-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Revised: 04/13/2012] [Accepted: 04/18/2012] [Indexed: 10/28/2022]
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8
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Wang X, Zhang H, Xu H, Qi P, Ji X, Wang Q, Wang X. Direct Chiral Determination of Acephate and Its Metabolite Methamidophos in Vegetables Using QuEChERS by Gas Chromatography–Tandem Mass Spectrometry. FOOD ANAL METHOD 2012. [DOI: 10.1007/s12161-012-9421-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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9
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Badea SL, Vogt C, Gehre M, Fischer A, Danet AF, Richnow HH. Development of an enantiomer-specific stable carbon isotope analysis (ESIA) method for assessing the fate of α-hexachlorocyclo-hexane in the environment. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:1363-1372. [PMID: 21504001 DOI: 10.1002/rcm.4987] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
α-Hexachlorocyclohexane (α-HCH) is the only chiral isomer of the eight 1,2,3,4,5,6-HCHs and we have developed an enantiomer-specific stable carbon isotope analysis (ESIA) method for the evaluation of its fate in the environment. The carbon isotope ratios of the α-HCH enantiomers were determined for a commercially available α-HCH sample using a gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) system equipped with a chiral column. The GC-C-IRMS measurements revealed δ-values of -32.5 ± 0.8‰ and -32.3 ± 0.5‰ for (-) α-HCH and (+) α-HCH, respectively. The isotope ratio of bulk α-HCH was estimated to be -32.4 ± 0.6‰ which was in accordance with the δ-values obtained by GC-C-IRMS (-32.7 ± 0.2‰) and elemental analyzer-isotope ratio mass spectrometry (EA-IRMS) of the bulk α-HCH (-32.1 ± 0.1‰). The similarity of the isotope ratio measurements of bulk α-HCH by EA-IRMS and GC-C-IRMS indicates the accuracy of the chiral GC-C-IRMS method. The linearity of the α-HCH ESIA method shows that carbon isotope ratios can be obtained for a signal size above 100 mV. The ESIA measurements exhibited standard deviations (2σ) that were mostly < ± 0.5‰. In order to test the chiral GC-C-IRMS method, the isotope compositions of individual enantiomers in biodegradation experiments of α-HCH with Clostridium pasteurianum and samples from a contaminated field site were determined. The isotopic compositions of the α-HCH enantiomers show a range of enantiomeric and isotope patterns, suggesting that enantiomeric and isotope fractionation can serve as an indicator for biodegradation and source characterization of α-HCH in the environment.
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Affiliation(s)
- Silviu-Laurentiu Badea
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
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10
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Chirality of organophosphorus pesticides: Analysis and toxicity. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:1277-84. [DOI: 10.1016/j.jchromb.2009.11.022] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 11/10/2009] [Accepted: 11/12/2009] [Indexed: 11/16/2022]
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11
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Li L, Zhou S, Jin L, Zhang C, Liu W. Enantiomeric separation of organophosphorus pesticides by high-performance liquid chromatography, gas chromatography and capillary electrophoresis and their applications to environmental fate and toxicity assays. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:1264-76. [DOI: 10.1016/j.jchromb.2009.10.031] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 10/26/2009] [Accepted: 10/29/2009] [Indexed: 11/15/2022]
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12
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Lecoeur-Lorin M, Delépée R, Morin P. Simultaneous enantioselective determination of fenamiphos and its two metabolites in soil sample by CE. Electrophoresis 2009; 30:2931-9. [DOI: 10.1002/elps.200800697] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Hühnerfuss H, Shah MR. Enantioselective chromatography—A powerful tool for the discrimination of biotic and abiotic transformation processes of chiral environmental pollutants. J Chromatogr A 2009; 1216:481-502. [DOI: 10.1016/j.chroma.2008.09.043] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Accepted: 09/11/2008] [Indexed: 10/21/2022]
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14
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Karásek L, Hajslová J, Rosmus J, Hühnerfuss H. Methylsulfonyl PCB and DDE metabolites and their enantioselective gas chromatographic separation in human adipose tissues, seal blubber and pelican muscle. CHEMOSPHERE 2007; 67:S22-7. [PMID: 17215020 DOI: 10.1016/j.chemosphere.2006.05.081] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/26/2006] [Indexed: 05/13/2023]
Abstract
In the present investigation, eleven human adipose tissue samples, two seal blubber samples and two pelican muscles samples were analyzed with regard to their concentrations of PCB parent compounds as well as to the respective chiral methylsulfonyl metabolites 3-MeSO2-CB 91, 4-MeSO2-CB 91, 3-MeSO2-CB 95, 4-MeSO2-CB 95, 3-MeSO2-CB 149, 4-MeSO2-CB 149, 3-MeSO2-CB 132, 4-MeSO2-CB 132, 3-MeSO2-CB 174, and 4-MeSO2-CB 174 and the achiral metabolites 3-MeSO2-CB 49, 4-MeSO2-CB 49, 3-MeSO2-CB 101, 4-MeSO2-CB 101, 3-MeSO2-CB 110, 4-MeSO2-CB 110 and 3-MeSO2-DDE. In order to verify enantioselective transformation processes and to compare the different enzymatic transformation pathways in birds and mammals, the enantioselective excesses of the chiral PCB-metabolites were determined by enantioselective gas chromatography with electron capture and mass spectrometric detection using modified cyclodextrin phases, including heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl-)-beta-cyclodextrin/OV1701 (1:1) for the parent PCBs and heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl-)-beta-cyclodextrin/SE52 (1:4) for the metabolites, respectively.
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Affiliation(s)
- Lubomír Karásek
- Department of Chemistry and Toxicology, Veterinary Institute Prague, Sídlistní 24, 16503 Praha 6, Czech Republic.
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15
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Marina ML, Crego AL. Capillary Electrophoresis: A Good Alternative for the Separation of Chiral Compounds of Environmental Interest. J LIQ CHROMATOGR R T 2006. [DOI: 10.1080/10826079708010980] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- M. L. Marina
- a Departamento de Química Analítica , Facultad de Ciencias Universidad de Alcalá de Henares , 28871, Alcalá de Henares (Madrid), Spain
| | - A. L. Crego
- a Departamento de Química Analítica , Facultad de Ciencias Universidad de Alcalá de Henares , 28871, Alcalá de Henares (Madrid), Spain
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16
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Pham-Tuan H, Larsson C, Hoffmann F, Bergman A, Fröba M, Hühnerfuss H. Enantioselective semipreparative HPLC separation of PCB metabolites and their absolute structure elucidation using electronic and vibrational circular dichroism. Chirality 2005; 17:266-80. [PMID: 15844204 DOI: 10.1002/chir.20158] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Polychlorinated biphenyls (PCBs) remain one of the most important groups of environmental contaminants. The fate (transformation) as well as the toxicological implications of the different metabolism steps are subject to considerable debate. The aim of this study is to start a comprehensive investigation of atropisomeric PCB metabolites, i.e., hydroxy, methoxy, methylthionyl, and methylsulfonyl PCBs in different biota. For this purpose, enantioselective semipreparative liquid chromatography is used to obtain pure enantiomers of PCB metabolites. Electronic circular dichroism (UV-CD) and vibrational circular dichroism (VCD) in combination with computational techniques were applied to determine their absolute structures. Approximately 18-25 mg of each enantiomer of the following metabolites were obtained using semipreparative HPLC on beta-cyclodextrin-based columns: 4-MeO-CB149, 4-MeS-CB149, 4-MeSO2-CB149, 3-MeS-CB149, and 3-MeSO2-CB149. The enantiomeric purity of the separated enantiomers was in the range of 95.0-99.9%. Rotational angles and absolute configurations were also determined. This study establishes a sound method for future preparation and absolute structure determination of compounds belonging to the same class.
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Affiliation(s)
- Hai Pham-Tuan
- University of Hamburg, Institute of Organic Chemistry, Hamburg, Germany.
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17
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18
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Harju M, Bergman A, Olsson M, Roos A, Haglund P. Determination of atropisomeric and planar polychlorinated biphenyls, their enantiomeric fractions and tissue distribution in grey seals using comprehensive 2D gas chromatography. J Chromatogr A 2003; 1019:127-42. [PMID: 14650610 DOI: 10.1016/j.chroma.2003.08.102] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
High prevalence of uterine occlusions and sterility is found among Baltic ringed and grey seal. Polychlorinated biphenyls (CBs) are suspected to be the main cause. The CB concentrations are higher in affected than in healthy animals, but the natural variation is considerable. Thus, it might be possible to assess the health status of seals by CB analysis. The ratios of chiral compounds (enantiomeric fractions (EFs)) such as atropisomeric CBs are of particularinterest, since these may reflect differences in metabolic rates. An analytical procedure was developed and used to determine the levels of atropisomeric CBs, planar-CBs (WHO-PCBs) and total CBs in seals of different health status. Comprehensive 2D gas chromatography (GC x GC) was used to separate the target analytes from other CBs and interferences and a micro electron-capture detector (microECD) was used for detection. EFs of the atropisomeric CBs were difficult to determine as the levels were low and the interferences many. Two column combinations bad to be used to avoid biased results-both had a chiral column as first-dimension column. The second-dimension column was coated with either a high-polarity cyanopropyl or a liquid crystal phase. EFs were determined for five atropisomeric CBs, i.e. CBs 91,95, 132, 149 and 174. The results were verified by GC x GC-time-of-flight mass spectrometry (TOF-MS). Some atropisomeric CBs had EFs that deviated strongly from the racemic-mixture value. The deviations were larger in liver than blubber, which indicates enantioselective metabolism. However, there was no selective passage of the studied atropisomeric CBs across placenta and no selective blood-brain barrier. Similarly, no correlation between EFs and health status was observed, although there was a correlation between the total CB levels and health status.
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Affiliation(s)
- Mikael Harju
- Department of Chemistry, Institute of Environmental Chemistry, Umeå University, SE-901 87 Umeå, Sweden.
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Affiliation(s)
- K Bester
- Institute for Environmental Research, University of Dortmund, Otto-Hahn Str.6, Germany.
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20
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Berger U, Vetter W, Götsch A, Kallenborn R. Chromatographic enrichment and enantiomer separation of axially chiral polybrominated biphenyls in a technical mixture. J Chromatogr A 2002; 973:123-33. [PMID: 12437170 DOI: 10.1016/s0021-9673(02)01112-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The separation properties of different chromatographic methods regarding the enantioselective separation of axially chiral (atropisomeric) polybrominated biphenyls (PBB) were studied. For this purpose, the technical hexabromobiphenyl product Firemaster BP-6 was characterised by gas-chromatography coupled to electron capture detection (GC/ECD) and electron-capture negative ion mass spectrometry (GC/ECNI-MS) as well as by liquid chromatographic fractionating on active carbon and celite. Twelve individual PBBs including potential atropisomeric PBBs were isolated from Firemaster BP-6 by reversed-phase high-performance liquid chromatography (HPLC) on three serially coupled octadecylsilane columns. Six of the 12 isolated PBBs (three tri-ortho and di-ortho substituted PBBs, respectively) were separated into atropisomers on a HPLC column containing permethylated beta-cyclodextrin on silica. Moreover, the temperature dependency of the enantiomer separations is discussed. Gas chromatographic enantiomer separation of PBBs is a very demanding task due to high elution temperatures. However, the atropisomers of one tri-ortho substituted PBB congener (PBB 149) could be resolved on a column coated with randomly modified heptakis(6-O-tert.-butyldimethylsilyl-2,3-di-O-methyl)-beta-cyclodextrin in OV 1701.
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Affiliation(s)
- Urs Berger
- Norwegian Institute for Air Research (NILU), The Polar Environmental Centre, Tromsø.
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21
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Vetter W, Jun W. Elucidation of a polychlorinated bipyrrole structure using enantioselective GC. Anal Chem 2002; 74:4287-9. [PMID: 12199604 DOI: 10.1021/ac025696o] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A hexachloro congener (Q1-hex) of the natural heptachloro-1'-methyl-1,2'-bipyrrole Q1 was recently observed as a byproduct of the Q1 synthesis. NMR investigation confirmed that Q1-hex has a proton on a carbon in beta-position to a nitrogen. Three isomers are possible that fulfill this prerequisite; unfortunately, however, the NMR data were not sufficient to distinguish among the three structural variants. Because only one isomer of Q1-hex is expected to be chiral, we utilized enantioselective gas chromatography and two chiral stationary phases to separate the atropisomers. Baseline separation of the Q1-hex atropisomers was obtained on 10% chemically bonded permethyl-beta-cyclodextrin. In the full-scan mode, it was found that Q1-hex was racemic and that both atropisomers had identical mass fragmentation patterns. Partial resolution of the Q1-hex atropisomers was obtained on 25% tert-butyldimethylsilylated beta-cyclodextrin diluted in PS086. In concert with previous NMR data, these enantioseparations prove that the structure of Q1-hex is 2,3,3',4',5,5'-hexachloro-1'-methyl-1,2'-bipyrrole (5). To our knowledge, this is the first gas chromatographic separation of atropisomers of an axially chiral 1,2'-bipyrrole derivative.
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Affiliation(s)
- Walter Vetter
- Friedrich-Schiller-Universität Jena, Lehrbereich Lebensmittelchemie, Germany.
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22
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Vetter W. ENANTIOSELECTIVE FATE OF CHIRAL CHLORINATED HYDROCARBONS AND THEIR METABOLITES IN ENVIRONMENTAL SAMPLES. FOOD REVIEWS INTERNATIONAL 2001. [DOI: 10.1081/fri-100000513] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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23
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Harju M, Haglund P. Comprehensive two-dimensional gas chromatography (GC�GC) of atropisomeric PCBs, combining a narrow bore ?-cyclodextrin column and a liquid crystal column. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/mcs.10010] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Wong CS, Garrison AW, Foreman WT. Enantiomeric composition of chiral polychlorinated biphenyl atropisomers in aquatic bed sediment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2001; 35:33-39. [PMID: 11352023 DOI: 10.1021/es0012570] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Enantiomeric ratios (ERs) for eight polychlorinated biphenyl (PCB) atropisomers were measured in aquatic sediment from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonracemic ERs for PCBs 91, 95, 132, 136, 149, 174, and 176 were found in sediment cores from Lake Hartwell, SC, which confirmed previous inconclusive reports of reductive dechlorination of PCBs at these sites on the basis of achiral measurements. Nonracemic ERs for many of the atropisomers were also found in bed-sediment samples from the Hudson and Housatonic Rivers, thus indicating that some of the PCB biotransformation processes identified at these sites are enantioselective. Patterns in ERs among congeners were consistent with known reductive dechlorination patterns at both river sediment basins. The enantioselectivity of PCB 91 is reversed between the Hudson and Housatonic River sites, which implies that the two sites have different PCB biotransformation processes with different enantiomer preferences.
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Affiliation(s)
- C S Wong
- Ecosystems Research Division, National Exposure Research Laboratory, U.S. Environmental Protection Agency, Athens, Georgia 30605, USA
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25
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Magnusson J, Blomberg LG, Claude S, Tabacchi R, Saxer A, Schürch S. Gas Chromatographic Enantiomer Separation of Atropisomeric PCBs Using Modified Cyclodextrins as Chiral Phases. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/1521-4168(20001101)23:11<619::aid-jhrc619>3.0.co;2-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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26
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Hühnerfuss H. Chromatographic enantiomer separation of chiral xenobiotics and their metabolites--a versatile tool for process studies in marine and terrestrial ecosystems. CHEMOSPHERE 2000; 40:913-919. [PMID: 10739026 DOI: 10.1016/s0045-6535(99)00333-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A review discussing methodical aspects of enantioselective chromatographic separation of chiral environmental xenobiotics as well as examples for process studies reported in literature. The process studies include microbial transformation of chiral pollutants in aquatic ecosystems, their enzymatic transformation in biota, their photochemical degradation, air/sea exchange processes and atmospheric long range transport, and enantioselective toxic effects.
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Affiliation(s)
- H Hühnerfuss
- Institute of Organic Chemistry, University of Hamburg, Germany.
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27
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Wong CS, Garrison AW. Enantiomer separation of polychlorinated biphenyl atropisomers and polychlorinated biphenyl retention behavior on modified cyclodextrin capillary gas chromatography columns. J Chromatogr A 2000; 866:213-20. [PMID: 10670811 DOI: 10.1016/s0021-9673(99)01104-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Seven commercially-available chiral capillary gas chromatography columns containing modified cyclodextrins were evaluated for their ability to separate enantiomers of the 19 stable chiral polychlorinated biphenyl (PCB) atropisomers, and for their ability to separate these enantiomers from achiral congeners, necessary for trace environmental analysis of chiral PCBs. The enantiomers of each of the 19 chiral PCBs were at least partially separated on one or more of these columns. Enantiomeric ratios of eleven atropisomers could also be quantified on six columns as they did not coelute with any other congener containing the same number of chlorine atoms, so could be quantified using gas chromatography-mass spectrometry. Analysis of a lake sediment heavily contaminated with PCBs showed enantioselective occurrence of PCB 91, proof positive of enantioselective in situ reductive dechlorination at the sampling site.
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Affiliation(s)
- C S Wong
- Ecosystems Research Division, National Exposure Research Laboratory, US Environmental Protection Agency, Athens, GA 30605-2700, USA
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28
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Enantiomeric separation of chiral polychlorinated biphenyls by micellar electrokinetic chromatography using mixtures of bile salts and sodium dodecyl sulphate with and without ?-cyclodextrin in the separation buffer. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/(sici)1520-667x(2000)12:1<33::aid-mcs5>3.0.co;2-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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29
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Chapter 6 Methods for the determination and evaluation of chlorinated biphenyls (CBs) in environmental matrices. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0167-9244(00)80012-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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30
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Zimmer D, Muschalek V, Müller C. Determination of metrifonate enantiomers in blood and brain samples using liquid chromatography on a chiral stationary phase coupled to tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2000; 14:1425-1432. [PMID: 10920365 DOI: 10.1002/1097-0231(20000815)14:15<1425::aid-rcm42>3.0.co;2-e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A novel enantioselective assay is described for the simultaneous determination of the metrifonate enantiomers BAY z 7216 and BAY z 7217 in extracts of whole blood samples obtained from rats, mice, rabbits and Beagle dogs as well as in rat brain tissue using liquid chromatography tandem mass spectrometry (LC/MS/MS) with thermally and pneumatically assisted electrospray ionization (TurboIonSpray(R)). Chromatographic separation is achieved on a chiral normal phase column with a mobile phase containing 0.25% water only. The total run time per sample is 11.0 min giving chromatographic base line separation of the enantiomers. Compared with previous methods this assay offers a higher sample throughput, excellent ruggedness and higher sensitivity. The limits of quantification for each enantiomer are 5.00 microg/L from 0.5 mL whole blood and 7.50 ng/g (ppb) using 0.333 g brain tissue, respectively. Similar assay specifications have been derived for the two enantiomers. The method has been validated for the analysis of blood samples from low and high dosed preclinical pharmacokinetic and toxicokinetic studies, corresponding to two analytical working ranges like e.g. 5.00 to 1000 microg/L and 200 to 40000 microg/L (0. 200 to 40.0 mg/L). For rat brain tissue the validated concentration range is 7.50 to 750 ng/g (ppb).
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Affiliation(s)
- D Zimmer
- Department of Preclinical Pharmacokinetics, Pharma Research Center, Bayer AG, D-42096 Wuppertal, Germany
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31
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Koske G, Leupold G, Angerhöfer D, Parlar H. Multidimensional gas chromatographic enantiomer quantification of some chlorinated xenobiotics in cod liver and fish oils. CHEMOSPHERE 1999; 39:683-688. [PMID: 10422255 DOI: 10.1016/s0045-6535(99)00132-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Four chiral HRGC column systems for the separation of selected organochlor pesticides and photoconversion products (heptachlor, cis- and trans-chlordane, o,p'-DDT, o,p'-DDD, and alpha-HCH) were tested. Cod hver oil and fish oil samples from different countries were comparatively analyzed. Of all these columns, the fourth was the most suitable one for the analysis of the selected compounds. The enantiomer ratios [ER] of cis-chlordane, trans-chlordane, photodieldrin, alpha-HCH, and o,p'-DDD in fish oils are nearly 1.0, while the ERs of the same substances are significantly different from 1.0 in cod liver oils. Contrary to that, the ER values of o,p'-DDT are remarkable different from 1 in the cod liver oils as well as in the fish oils.
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Affiliation(s)
- G Koske
- Chair for Chemical Technical Analysis and Chemical Food Technology, Technical University Munich, Freising-Weihenstephan-Germany
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32
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Use of 6-O-tert.-butyldimethylsilylated ß-cyclodextrins for the enantioseparation of chiral organochlorine compounds. J Chromatogr A 1999. [DOI: 10.1016/s0021-9673(98)01073-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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33
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Bicchi C, D'Amato A, Rubiolo P. Cyclodextrin derivatives as chiral selectors for direct gas chromatographic separation of enantiomers in the essential oil, aroma and flavour fields. J Chromatogr A 1999; 843:99-121. [PMID: 10399852 DOI: 10.1016/s0021-9673(99)00202-2] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
This article reviews papers published over the period 1995-1998 dealing with the application of cyclodextrin derivatives (CDs) as chiral selector for direct enantiomer GC separation of volatile optically active components in the essential oil, extract, flavour and aroma fields. For each application, the racemate analysed, the CD employed as chiral selector and the matrix investigated are reported. The applications are grouped by analytical technique employed: capillary gas chromatography and capillary gas chromatography-mass spectrometry (GC and GC-MS); two-dimensional gas chromatography (GC x GC); capillary gas chromatography-isotope ratio-mass spectrometry (GC-IRMS); liquid chromatography-capillary gas chromatography (LC-GC).
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34
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Cochran JW, Frame GM. Recent developments in the high-resolution gas chromatography of polychlorinated biphenyls. J Chromatogr A 1999; 843:323-68. [PMID: 10399859 DOI: 10.1016/s0021-9673(99)00063-1] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The capillary gas chromatography of polychlorinated biphenyls (PCBs) is reviewed. Focus is on the most recent developments in the separation and detection of PCBs rather than sample preparation methods. Included are a comprehensive look at stationary phases that have been used to separate PCBs and the relatively new work on chiral separations of PCBs. Mass spectrometry and atomic emission are presented as selective detection techniques. Suggestions for additional research are proposed where appropriate.
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Affiliation(s)
- J W Cochran
- Waste Management and Research Center, Champaign, IL 61820, USA
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35
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Lin WC, Chang FC, Kuei CH. Separation of atropisomeric polychlorinated biphenyls by cyclodextrin modified micellar electrokinetic chromatography. ACTA ACUST UNITED AC 1999. [DOI: 10.1002/(sici)1520-667x(1999)11:3<231::aid-mcs9>3.0.co;2-s] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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36
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Bicchi C, Cravotto G, D'amato A, Rubiolo P, Galli A, Galli M. Cyclodextrin derivatives in gas chromatographic separation of racemates with different volatility. Part XV: 6-O-t-butyldimethylsilyl- versus 6-O-t-hexyldimethylsilyl-? and -? derivatives. ACTA ACUST UNITED AC 1999. [DOI: 10.1002/(sici)1520-667x(1999)11:7<487::aid-mcs1>3.0.co;2-b] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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37
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Wiberg K, Letcher R, Sandau C, Duffe J, Norstrom R, Haglund P, Bidleman T. Enantioselective gas chromatography/mass spectrometry of methylsulfonyl PCBs with application to arctic marine mammals. Anal Chem 1998; 70:3845-52. [PMID: 9751025 DOI: 10.1021/ac980064g] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Four different commercially available cyclodextrin (CD) capillary gas chromatography (GC) columns were tested for the enantioselective separation of nine environmentally persistent atropisomeric 3- and 4-methylsulfonyl PCBs (MeSO2-CBs). The selected columns contained cyclodextrins with various cavity diameters (beta- or gamma-CD), which were methylated and/or tert-butyldimethylsilylated (TBDMS) in the 2,3,6-O-positions. The beta-CD column with TBDMS substituents in all of the 2,3,6-O-positions was by far the most selective column for the MeSO2-CBs tested. Enantiomers of congeners with 3-MeSO2 substitution were more easily separated than those with 4-MeSO2 substitution. The separation also seemed to be enhanced for congeners with the chlorine atoms on the non-MeSO2-containing ring and clustered on one side of the same ring. The 2,3-di-O-methyl-6-O-TBDMS-beta-CD was found to give somewhat better selectivity than the corresponding gamma-CD, in comparison between the two columns, which were identical in all other respects. Enantioselective analysis of arctic ringed seal (Phoca hispida) and polar bear (Ursus maritimus) adipose tissue revealed a strong dominance of certain enantiomers. For example, the enantiomer ratio (ER) of 3-MeSO2-CB149 was 0.32 and < 0.1 in ringed seal blubber and polar bear fat, respectively. These low ER values are indicative of highly enantioselective formation, enantioselective metabolism, enantioselective transport across cell membranes, or a combination of the three in both species. Comparable results for the enantiomeric analysis of MeSO2-CBs in biotic tissue extracts were obtained using two highly selective mass spectrometric techniques, ion trap mass spectrometry/mass spectrometry and electron capture negative ion low-resolution mass spectrometry.
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Affiliation(s)
- K Wiberg
- Institute of Environmental Chemistry, Umeå University, Sweden.
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38
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Crego AL, Gonzalez MJ, Marina ML. Chiral separation of polychlorinated biphenyls by micellar electrokinetic chromatography with sodium cholate. Electrophoresis 1998; 19:2113-8. [PMID: 9761190 DOI: 10.1002/elps.1150191212] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Micellar electrokinetic chromatography (MEKC) with one kind of bile salt (sodium cholate) was used to separate three chiral polychlorinated biphenyls (PCBs; 84, 95, and 176), each one in its two enantiomers. Sodium cholate was used as chiral surfactant in a 2-(N-cyclohexylamino) ethanesulfonic acid (CHES) buffer under alkaline (pH 10) conditions containing urea (2 M). The influence of bile salt concentration on the efficiency and the resolution between the two enantiomers of PCBs 84 and 95 was established. The chiral separation of three PCBs was successfully achieved in less than 30 min (approximately 23 min for PCB 176 and approximately 29 min for PCBs 84 and 95).
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Affiliation(s)
- A L Crego
- Departamento de Química Analítica, Facultad de Ciencias, Universidad de Alcalá, Alcalá de Henares (Madrid), Spain.
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39
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Beier T, Höltje HD. Modified cyclodextrins as chiral selectors: molecular modelling investigations on the enantioselective binding properties of heptakis(2,3-di-O-methyl-6-O-tert.-butyldimethylsilyl)-beta-cyclodextri n. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 708:1-20. [PMID: 9653941 DOI: 10.1016/s0378-4347(97)00636-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Molecular modelling methods have been used to investigate the enantioselective binding properties of chiral dihydrofuranones on heptakis(2,3-di-O-methyl-6-O-tert.-butyldimethylsilyl)-beta-cyclod extrin in capillary gas chromatography. A conformational analysis of the modified beta-cyclodextrin was performed using annealed molecular dynamics. With the program GRID the molecular interaction potential for each of the received energetically reasonable structures of the beta-cyclodextrin and the dihydrofuranones was evaluated using different probe groups. The results of these computations have been used as starting points for constructing geometrically reasonable host-guest complexes between the beta-cyclodextrin and the dihydrofuranones. The subsequently performed molecular dynamics simulations yielded different complex states reflecting the conformational flexibility of the diastereomeric complexes. Considering the evaluated interaction energy between the beta-cyclodextrin and the dihydrofuranones as a measure of complex stability the results are in close agreement with the experimentally determined elution sequences. The methodology for the construction of the interaction model used in this study is capable of simulating the experimental data. We believe that it may serve as a basis for predictions of hitherto unknown elution sequences at modified cyclodextrins.
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Affiliation(s)
- T Beier
- Institute of Pharmacy, Free University of Berlin, Germany
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40
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Enantioselective Separations. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0301-4770(08)60303-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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41
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Benick� E, Tak�?ov� D, Krup?�k J, Ska?�ni I, Onuska F, Terry K. Gas chromatographic separation of PCB atropisomers on cyclodextrin stationary phases. Chirality 1998. [DOI: 10.1002/(sici)1520-636x(1998)10:6<540::aid-chir7>3.0.co;2-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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42
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43
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Vetter W, Schurig V. Enantioselective determination of chiral organochlorine compounds in biota by gas chromatography on modified cyclodextrins. J Chromatogr A 1997; 774:143-75. [PMID: 9253189 DOI: 10.1016/s0021-9673(97)00296-3] [Citation(s) in RCA: 126] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Approaches to the gas chromatographic enantiomer separation of chiral organchlorines (alpha-hexachlorocyclohexane, cis- and trans-chlordane, heptachlor, heptachlorepoxide, oxychlordane, o,p'-DDT, compounds of technical toxaphene and stable atropisomeric polychlorinated biphenyls) are reviewed. Chiral stationary phases based on cyclodextrin derivatives and used for the gas chromatographic enantiomer separation of the chiral organochlorines are described. Enantiomeric ratios of chiral organochlorines in technical mixtures and biological samples are reported and discussed.
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Affiliation(s)
- W Vetter
- Friedrich-Schiller-Universität Jena, Institut für Ernährung und Umwelt, Germany
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44
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Enantiomer separation of selected atropisomeric polychlorinated biphenyls including PCB 144 on tert.-butyldimethylsilylated β-cyclodextrin. J Chromatogr A 1997. [DOI: 10.1016/s0021-9673(97)00082-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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45
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Vetter W, Klobes U, Hummert K, Luckas B. Gas chromatographic separation of chiral organochlorines on modified cyclodextrin phases and results of marine biota samples. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/jhrc.1240200208] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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46
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Biedermann PU, Schurig V, Agranat I. Enantiomerization of Environmentally Significant Overcrowded Polychlorinated Biphenyls (PCBs). Chirality 1997. [DOI: 10.1002/(sici)1520-636x(1997)9:4<350::aid-chir6>3.0.co;2-h] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Marina ML, Benito I, Díez-Masa JC, González MJ. Separation of chiral polychlorinated biphenyls by micellar electrokinetic chromatography using beta- and gamma-cyclodextrin mixtures in the separation buffer. J Chromatogr A 1996; 752:265-70. [PMID: 8962501 DOI: 10.1016/s0021-9673(96)00506-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Chiral polychlorinated biphenyls (PCBs) 45, 84, 88, 91, 95, 132, 136, 139, 149, 171, 183 and 196 were separated each in its two enantiomers by cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC). Mixtures of beta- and gamma-cyclodextrins were used as chiral modifiers in a 2-(N-cyclohexylamino)ethanesulphonic acid (CHES) buffer containing urea and sodium dodecyl sulphate (SDS) micelles. Separations of multicomponent mixtures of PCBs into their enantiomers were also performed. A mixture of PCBs 45, 88, 91, 95, 136, 139, 149 and 196 was separated into all sixteen enantiomers in an analysis time of approx. 35 min.
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Affiliation(s)
- M L Marina
- Departamento de Química Analítica, Facultad de Ciencias, Universidad de Alcalá de Henares, Madrid, Spain
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48
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Bicchi C, D'Amato A, Manzin V, Galli A, Galli M. Cyclodextrin derivatives in the gas chromatographic separation of racemic mixtures of volatile compounds X. 2,3-Di-O-ethyl-6-O-tert.-butyldimethylsilyl-β- and −γ-cyclodextrins. J Chromatogr A 1996. [DOI: 10.1016/0021-9673(96)00254-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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49
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Haglund P, Wiberg K. Determination of the gas chromatographic elution sequences of the (+)- and (−)-enantiomers of stable atropisomeric PCBs on Chirasil-dex. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/jhrc.1240190703] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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50
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Affiliation(s)
- Gary A. Eiceman
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003
| | - Herbert H. Hill
- Department of Chemistry, Washington State University, Pullman, Washington 99164
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