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Negatively charged cyclodextrins: Synthesis and applications in chiral analysis-A review. Carbohydr Polym 2020; 256:117517. [PMID: 33483038 DOI: 10.1016/j.carbpol.2020.117517] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/02/2020] [Accepted: 12/11/2020] [Indexed: 12/12/2022]
Abstract
The negatively charged cyclodextrins (CDs) play an important role in chiral analysis due to the additional electrostatic effect beyond the host-guest inclusion, especially in enantioanalysis of positively charged and electrically neutral analytes. This review presents recent advances in application of anionic CDs for enantioanalysis during the past five years. Firstly, the synthesis approaches of random substitution and single isomers of anionic CDs are briefly discussed. The main part focuses on the chiral analysis using anionic CDs in various analytical techniques, including capillary electrophoresis, high-performance liquid chromatography, capillary electrochromatography, counter current chromatography, nuclear magnetic resonance, etc. Particular attention is given to the capillary electrophoresis application since charged CDs could be used as a carrier of enantiomers by virtue of their self-mobility and offer an easy adjustment of the enantiomer migration order. Finally, future opportunities are also discussed in the conclusion of this review.
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2
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Baca M, Kryj A, Naghdi E, Gelin P, Sukas S, Laha P, Terryn H, Ottevaere H, De Malsche W. Performance of laterally elongated pillar array columns in capillary electrochromatography mode. Electrophoresis 2020; 41:1287-1295. [DOI: 10.1002/elps.202000001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 01/03/2023]
Affiliation(s)
- Martyna Baca
- μFlow groupDepartment of Chemical EngineeringVrije Universiteit Brussel Brussels Belgium
| | - Agata Kryj
- μFlow groupDepartment of Chemical EngineeringVrije Universiteit Brussel Brussels Belgium
| | - Elahe Naghdi
- Faculty of ChemistryShahid Beheshti University, G.C. Tehran Iran
| | - Pierre Gelin
- μFlow groupDepartment of Chemical EngineeringVrije Universiteit Brussel Brussels Belgium
| | - Sertan Sukas
- μFlow groupDepartment of Chemical EngineeringVrije Universiteit Brussel Brussels Belgium
| | - Priya Laha
- Research Group Electrochemical and Surface Engineering (SURF)Vrije Universiteit Brussel Brussels Belgium
| | - Herman Terryn
- Research Group Electrochemical and Surface Engineering (SURF)Vrije Universiteit Brussel Brussels Belgium
| | - Heidi Ottevaere
- Department of Applied Physics and PhotonicsVrije Universiteit Brussel Brussels Belgium
| | - Wim De Malsche
- μFlow groupDepartment of Chemical EngineeringVrije Universiteit Brussel Brussels Belgium
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3
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Electrochromatographic behavior of core-shell particles: A comparison study. Anal Chim Acta 2018; 1033:205-212. [DOI: 10.1016/j.aca.2018.06.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 05/09/2018] [Accepted: 06/02/2018] [Indexed: 11/22/2022]
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4
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Chen Z, Huang C, Liu W, Zhang L, Tong P, Zhang L. Simultaneous determination of nucleoside and purine compounds in human urine based on a hydrophobic monolithic column using capillary electrochromatography. Electrophoresis 2015; 36:2727-2735. [DOI: 10.1002/elps.201500194] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 08/05/2015] [Accepted: 08/06/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Zongbao Chen
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, College of Chemistry, Testing Center; Fuzhou University; Fuzhou Fujian China
- Key Laboratory of Applied Organic Chemistry, Department of Chemistry; Shangrao Normal University; Shangrao Jiangxi China
| | - Chuanghui Huang
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, College of Chemistry, Testing Center; Fuzhou University; Fuzhou Fujian China
| | - Wei Liu
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, College of Chemistry, Testing Center; Fuzhou University; Fuzhou Fujian China
| | - Lin Zhang
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, College of Chemistry, Testing Center; Fuzhou University; Fuzhou Fujian China
| | - Ping Tong
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, College of Chemistry, Testing Center; Fuzhou University; Fuzhou Fujian China
| | - Lan Zhang
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, College of Chemistry, Testing Center; Fuzhou University; Fuzhou Fujian China
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5
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Chen Z, Ye Q, Liu L, Dong H. Simultaneous Determination of Five Alkaloid Compounds in a Drug Based on a Hydrophilic Monolithic Column by Capillary Electrochromatography. J Chromatogr Sci 2015; 54:88-95. [PMID: 26187925 DOI: 10.1093/chromsci/bmv096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Indexed: 11/13/2022]
Abstract
A novel capillary electrochromatography (CEC) method was developed by using a hydrophilic monolithic column for the simultaneous determination of five alkaloids in a drug. The monolithic stationary phase was first prepared via in situ polymerization of acrylamide (AM), glycidyl methacrylate (GMA), N,N'-methylenebisacrylamide (MBA) and 2-acrylamido-2-methyl-1-propane-sulfonic acid (AMPS) in a ternary porogen solvent system consisting of cyclohexanol, dodecanol and toluene. The obtained monolithic stationary phase was subsequently modified by 0.1 mol/L ammonia water for opening epoxide groups of GMA. The separation performance and efficiency of the resulting monolithic column were investigated by the use of five compounds (thiourea, aniline, naphthylamine, diphenylamine and dimethyl acetamide) by CEC. The optimized monolithic column has obtained high column efficiencies with 74,000-121,000 theoretical plates/m. Finally, the prepared monolithic column was used to separate and determine five alkaloids (piperine, nuciferine, kukoline, berberine and tetrandrine) using CEC. Under the conditions of acetonitrile/10 mM phosphate buffer solution (65/35, v/v, pH 8.5) and 15 kV applied voltage, the baseline separation of five alkaloids was achieved. The proposed method has been successfully applied to the determination of berberine in a tablet sample. The percentage of recovery of spiked tablet samples ranged from 93.4 to 108.0% with relative standard deviations (RSDs) <9.20%.
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Affiliation(s)
- Zongbao Chen
- Key Laboratory of Applied Organic Chemistry, College of Jiangxi Province, Department of Chemistry, Shangrao Normal University, Shangrao, Jiangxi 334001, PR China Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Fuzhou University, Fuzhou, Fujian 335002, PR China
| | - Qing Ye
- Key Laboratory of Applied Organic Chemistry, College of Jiangxi Province, Department of Chemistry, Shangrao Normal University, Shangrao, Jiangxi 334001, PR China
| | - Linghai Liu
- Key Laboratory of Applied Organic Chemistry, College of Jiangxi Province, Department of Chemistry, Shangrao Normal University, Shangrao, Jiangxi 334001, PR China
| | - Hongxia Dong
- Key Laboratory of Applied Organic Chemistry, College of Jiangxi Province, Department of Chemistry, Shangrao Normal University, Shangrao, Jiangxi 334001, PR China
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6
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Enantioseparation of basic chiral compounds on a clindamycin phosphate-silica/zirconia hybrid monolith by capillary electrochromatography. J Chromatogr A 2014; 1356:289-93. [DOI: 10.1016/j.chroma.2014.06.089] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 06/26/2014] [Accepted: 06/26/2014] [Indexed: 11/24/2022]
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7
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De Smet S, Lynen F. Kinetic performance evaluation and perspectives of contemporary packed column capillary electrochromatography. J Chromatogr A 2014; 1355:261-8. [DOI: 10.1016/j.chroma.2014.06.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/03/2014] [Accepted: 06/04/2014] [Indexed: 12/31/2022]
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8
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Hałka-Grysińska A, Płocharz PW, Torbicz A, Skwarek E, Janusz W, Dzido TH. Influence of the Modifier Type and its Concentration on Electroosmotic Flow of the Mobile Phase in Pressurized Planar Electrochromatography. Chromatographia 2014; 77:941-950. [PMID: 25067847 PMCID: PMC4077256 DOI: 10.1007/s10337-014-2689-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 04/15/2014] [Accepted: 04/28/2014] [Indexed: 11/27/2022]
Abstract
The aim of this work was to find a relationship between electroosmotic flow (EOF) velocity of the mobile phase in pressurized planar electrochromatography (PPEC) and physicochemical properties like zeta potential, dielectric constant, and viscosity of the mobile phase as well as its composition. The study included different types of organic modifiers (acetonitrile, methanol, ethanol, acetone, formamide, N-methylformamide and N,N-dimethylformamide) in the full concentration range. In all experiments, chromatographic glass plates HPTLC RP-18 W from Merck (Darmstadt) were used as a stationary phase. During the study we found that there is no linear correlation between EOF velocity of the mobile phase and single variables such as zeta potential or dielectric constant or viscosity. However, there is quite strong linear correlation between EOF velocity of the mobile phase and variable obtained by multiplying zeta potential of the stationary phase-mobile phase interface, by dielectric constant of the mobile phase solution and dividing by viscosity of the mobile phase. Therefore, it could be concluded that the PPEC system fulfilled the Helmholtz-Smoluchowski equation.
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Affiliation(s)
| | - Paweł W Płocharz
- Department of Cosmetology, Faculty of Physical Education and Sport in Biala Podlaska, Jozef Pilsudski University of Physical Education in Warsaw, Biala Podlaska, Poland
| | - Andrzej Torbicz
- Department of Physical Chemistry, Medical University of Lublin, Lublin, Poland
| | - Ewa Skwarek
- Department of Radiochemistry and Colloid Chemistry, Maria Curie-Skłodowska University, Lublin, Poland
| | - Władysław Janusz
- Department of Radiochemistry and Colloid Chemistry, Maria Curie-Skłodowska University, Lublin, Poland
| | - Tadeusz H Dzido
- Department of Physical Chemistry, Medical University of Lublin, Lublin, Poland
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9
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Keunchkarian S, Lebed PJ, Sliz BB, Castells CB, Gagliardi LG. New method for sintering silica frits for capillary microcolumns. Anal Chim Acta 2014; 820:168-75. [DOI: 10.1016/j.aca.2014.02.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 02/12/2014] [Accepted: 02/16/2014] [Indexed: 11/29/2022]
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10
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Gökaltun A, Aydoğan C, Çelebi B, Denizli A, Tuncel A. Preparation of an Electrochromatographic Stationary Phase Using a New Polymethacrylate Monolith with Chloropropyl Functionality. Chromatographia 2014. [DOI: 10.1007/s10337-013-2620-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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11
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Mishchuk NA, Lysenko LL, Nesmeyanova TA. Nonstationary processes in an ion-exchange membranes-diaphragm-ion-exchange resin system. 2. Electroosmosis. COLLOID JOURNAL 2013. [DOI: 10.1134/s1061933x13050116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Lin H, Zhang Z, Dong J, Liu Z, Ou J, Zou H. Preparation of polyhedral oligomeric silsesquioxane based hybrid monoliths by ring-opening polymerization for capillary LC and CEC. J Sep Sci 2013; 36:2819-25. [DOI: 10.1002/jssc.201300417] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Revised: 05/28/2013] [Accepted: 05/28/2013] [Indexed: 11/07/2022]
Affiliation(s)
- Hui Lin
- CAS Key Laboratory of Separation Science for Analytical Chemistry; National Chromatographic R & A Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS); Dalian China
- University of Chinese Academy of Sciences; Beijing China
| | - Zhenbin Zhang
- CAS Key Laboratory of Separation Science for Analytical Chemistry; National Chromatographic R & A Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS); Dalian China
- University of Chinese Academy of Sciences; Beijing China
| | - Jing Dong
- CAS Key Laboratory of Separation Science for Analytical Chemistry; National Chromatographic R & A Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS); Dalian China
| | - Zhongshan Liu
- CAS Key Laboratory of Separation Science for Analytical Chemistry; National Chromatographic R & A Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS); Dalian China
- University of Chinese Academy of Sciences; Beijing China
| | - Junjie Ou
- CAS Key Laboratory of Separation Science for Analytical Chemistry; National Chromatographic R & A Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS); Dalian China
| | - Hanfa Zou
- CAS Key Laboratory of Separation Science for Analytical Chemistry; National Chromatographic R & A Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS); Dalian China
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13
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14
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KITAGAWA F, SUDAKI H, SUEYOSHI K, OTSUKA K. Open-tubular Electrochromatographic Chiral Separation of Amino Acids Using an Organic Nanocrystals Immobilized Capillary. ANAL SCI 2013; 29:107-12. [DOI: 10.2116/analsci.29.107] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Fumihiko KITAGAWA
- Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University
| | - Hiroshi SUDAKI
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University
| | - Kenji SUEYOSHI
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University
| | - Koji OTSUKA
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University
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15
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The characteristics of open-tubular capillary electrochromatography columns with series/mixed stationary phases constructed with magnetic nanoparticle coating. Talanta 2013; 104:173-9. [DOI: 10.1016/j.talanta.2012.11.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2012] [Revised: 11/03/2012] [Accepted: 11/08/2012] [Indexed: 12/17/2022]
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16
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D’Orazio G, Rocchi S, Fanali S. Nano-liquid chromatography coupled with mass spectrometry: Separation of sulfonamides employing non-porous core–shell particles. J Chromatogr A 2012; 1255:277-85. [DOI: 10.1016/j.chroma.2012.03.032] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 03/06/2012] [Accepted: 03/10/2012] [Indexed: 11/25/2022]
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17
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Kopeć KK, Wessling M, Stamatialis DF. Porous membrane structures as stationary phase for capillary electrochromatography. Electrophoresis 2012; 33:2892-5. [PMID: 22911277 DOI: 10.1002/elps.201200275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 06/15/2012] [Accepted: 06/17/2012] [Indexed: 11/07/2022]
Abstract
This work presents the application of membrane technology for the fabrication of stationary phase for CEC columns using the technique based on phase inversion of polymer solution. A blend of polyimide P84 and sulphonated poly(ether ether ketone was processed via immersion precipitation dry-wet spinning into small-bore porous fiber. The morphology, zeta potential, and performance of the porous structure in the CEC separation were investigated. Noncharged molecules (as markers of the electroosmotic flow) and small organic compounds were injected into the column, driven under the application of voltage, and detected on the electropherogram. The proof of concept of applying porous membrane structure as stationary phase for CEC was shown and possible optimization to improve efficiency and selectivity was suggested.
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Affiliation(s)
- Karina K Kopeć
- Institute for Biomedical Technology and Technical Medicine, University of Twente, AE Enschede, The Netherlands
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18
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D’Orazio G, Fanali S. C18 silica packed capillary columns with monolithic frits prepared with UV light emitting diode: Usefulness in nano-liquid chromatography and capillary electrochromatography. J Chromatogr A 2012; 1232:176-82. [DOI: 10.1016/j.chroma.2011.11.056] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 11/24/2011] [Accepted: 11/28/2011] [Indexed: 11/26/2022]
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19
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Wang Y, Deng QL, Fang GZ, Pan MF, Yu Y, Wang S. A novel ionic liquid monolithic column and its separation properties in capillary electrochromatography. Anal Chim Acta 2012; 712:1-8. [DOI: 10.1016/j.aca.2011.10.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 09/29/2011] [Accepted: 10/11/2011] [Indexed: 11/30/2022]
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20
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Mishchuk NA. Concentration polarization of interface and non-linear electrokinetic phenomena. Adv Colloid Interface Sci 2010; 160:16-39. [PMID: 20810097 DOI: 10.1016/j.cis.2010.07.001] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2010] [Revised: 07/04/2010] [Accepted: 07/05/2010] [Indexed: 10/19/2022]
Abstract
The review addresses the peculiarities of concentration polarization caused by an electric current passing through conducting and around nonconducting charged materials. The conditions of emergence of an induced space charge of large density and thickness behind an electrical double layer, leading to strong non-linearity of electroosmosis and electrophoresis, are analyzed. Basic findings about concentration polarization, its theoretical modeling and experimental investigations, as well as its influence on electrokinetic phenomena and mass transfer through ion-exchange materials are discussed from the point of view of the fundamental knowledge about polarization processes and from the perspective of their practical application. The analysis focuses on the main properties of concentration polarization, electroosmotic flow of liquid around single fixed particles and through the system of particles, and electrophoresis of particles suspended in aqueous medium and current through flat, spherical and cylindrical interfaces and membranes with heterogeneous conductivity. The paper also presents the general ideas of concentration polarization and non-linear electrokinetic phenomena in case of nonconducting particles and their dependence on particle surface electroconductivity. Existing theoretical models describing polarization of nonconducting particles at high and low Peclet numbers are analyzed, with appropriate experimental data being provided to validate the theory. A joint analysis of polarization of conducting and nonconducting particles completes the review.
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21
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Assay of vitamin B in urine by capillary electrochromatography with methacrylate-based monolithic column. Electrophoresis 2010; 31:3227-32. [DOI: 10.1002/elps.201000147] [Citation(s) in RCA: 8] [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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22
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Zhang X, Lin X, Chen Z, Wang X, Wu X, Xie Z. Triamine-bonded stationary phase for open tubular capillary electrochromatography. J Sep Sci 2010; 33:3184-93. [DOI: 10.1002/jssc.201000174] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Chen Z, Cai Y, Cheng J, Zhang L. Electrochromatographic characterization of methacrylate ester-based monolith and capillary electrochromatography separation of flavonoids. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:2375-8. [DOI: 10.1016/j.jchromb.2010.07.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 06/22/2010] [Accepted: 07/08/2010] [Indexed: 10/19/2022]
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24
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Coupling capillary electrochromatography with mass spectrometry by using a liquid-junction nano-spray interface. J Chromatogr A 2010; 1217:4079-86. [DOI: 10.1016/j.chroma.2009.11.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 09/16/2009] [Accepted: 11/02/2009] [Indexed: 11/23/2022]
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25
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Ding G, Zhang J, Bao JJ. Preparation and evaluation of amphiphilic silica-based monolithic column having surface-bound octanoyl-aminopropyl moieties for capillary electrochromatography. Electrophoresis 2010; 31:1983-90. [DOI: 10.1002/elps.200900712] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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26
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Preparation of organic–inorganic hybrid silica monolith with octyl and sulfonic acid groups for capillary electrochromatograhpy and application in determination of theophylline and caffeine in beverage. J Chromatogr A 2010; 1217:3547-56. [DOI: 10.1016/j.chroma.2010.03.032] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Revised: 03/14/2010] [Accepted: 03/19/2010] [Indexed: 11/22/2022]
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27
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Nischang I, Höltzel A, Tallarek U. Electrochromatographic retention of peptides on strong cation-exchange stationary phases. Electrophoresis 2010; 31:933-43. [DOI: 10.1002/elps.200900549] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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28
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Nischang I, Tallarek U. Inherent peak compression of charged analytes in electrochromatography. J Sep Sci 2010; 32:3157-68. [PMID: 19746396 DOI: 10.1002/jssc.200900436] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This work resolves peak compression of charged analytes in CEC with strong cation-exchange stationary phase particles. By combining electrochromatographic peak shape analysis with the results of numerical simulations and confocal laser scanning microscopy in the packed capillaries, we identify electrical field-induced concentration polarization as the key physical phenomenon responsible for the inherent existence of local electrical field gradients on the scale of an individual support particle. Consequently, positive and negative field gradients exist between and inside the particles along the whole packing. Their intensity depends on the particles cation-selectivity (governed by the particles volume charge density and the mobile phase ionic strength) and the applied field strength. The interplay of these local field gradients with the analytes retention (intraparticle adsorption) determines whether fronting, tailing, or spiked analyte peaks are observed, and it provides a mechanism by which strongly retained analytes can be eluted over long distances with little zone dispersion. Our analysis explains the "anomalous" peak compression effects with strong cation-exchange particles, which have been reported more than a decade ago (Smith, N. W., Evans, M. B., Chromatographia 1995, 41, 197-203) and since then remained largely unresolved.
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Affiliation(s)
- Ivo Nischang
- Department of Chemistry, Philipps-Universität Marburg, Marburg, Germany
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29
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Study of peak shape and efficiency in butyl acrylate-based monolithic columns for capillary electrochromatography. J Chromatogr A 2009; 1216:6831-7. [DOI: 10.1016/j.chroma.2009.08.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 06/09/2009] [Accepted: 08/07/2009] [Indexed: 11/18/2022]
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30
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Yone Á, Carballo RR, Rezzano IN, Vizioli NM. Separation of peptides by open-tubular capillary electrochromatography using Fe(III)-deuteroporphyrin as a covalently attached stationary phase. Electrophoresis 2009; 30:2293-9. [DOI: 10.1002/elps.200800855] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Wang H, Cao J, Bi Y, Chen L, Wan QH. Magnetically immobilized frits for the preparation of packed columns used in capillary electrochromatography. J Chromatogr A 2009; 1216:5882-7. [PMID: 19559442 DOI: 10.1016/j.chroma.2009.06.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 05/26/2009] [Accepted: 06/03/2009] [Indexed: 11/17/2022]
Abstract
Fabrication of porous frits to retain stationary phases is a critical issue in column preparation for capillary electrochromatography (CEC). In this work, porous frits were prepared by applying an external magnetic field to magnetically responsive particles placed inside a fused-silica capillary. Three batches of uniform magnetite spheres with particle diameters of 0.3, 0.4, and 0.6 microm and saturation magnetization values of 73.03, 74.41, and 77.83 emu/g, respectively, were used as frit particles and octadecyl- and phenyl-bonded silica gels were packed successfully into frit-containing capillaries. The performance of the resulting magnetically immobilized frits and packed columns was evaluated. The electroosmotic mobilities in capillaries containing outlet frit only were found to be reduced by 2-4% whereas the plate heights of an unretained marker increased by 30-50% as compared to those in open capillaries. These variations are believed to be associated with the inhomogeneities of the packed structure of the frits. The magnetically immobilized frits showed adequate mechanical strength to withstand the flow drag force, allowing separation in capillaries packed with 5-mum stationary phases up to 10-15 cm, thus rendering column efficiency and reproducibility comparable with those obtained with sintered frits. Taken together, retaining frits made of uniform magnetite particles serves as a viable alternative to sintered frits for column preparation, which offers several distinct advantages such as ease of preparation, improved durability as compared to sintered frits where the removal of the polyimide coating makes the packed column susceptible to breakage, and use of large-bore capillaries for semipreparative separations.
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Affiliation(s)
- Hongling Wang
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
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Chen D, Wang J, Jiang Y, Zhou T, Fan G, Wu Y. Separation and determination of coumarins in Fructus cnidii extracts by pressurized capillary electrochromatography using a packed column with a monolithic outlet frit. J Pharm Biomed Anal 2009; 50:695-702. [PMID: 19608371 DOI: 10.1016/j.jpba.2009.05.026] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 04/30/2009] [Accepted: 05/22/2009] [Indexed: 11/18/2022]
Abstract
The pressurized capillary electrochromatography (pCEC) was utilized for the separation and determination of coumarins in Fructus cnidii extracts from 12 different regions. After a thorough study of analytical parameters such as acetonitrile content of the mobile phase, the concentration and pH of the buffer, and the applied voltage, a methodology was proposed to separate and determine six coumarins of F. cnidii extracts in less than 15 min. The experiments were performed in an in-house packed column with a monolithic outlet frit under the optimal conditions: pH 4.0 ammonium acetate buffer at 10 mM containing 50% acetonitrile at -6kV applied voltage. The calibration curves were linear in the range of 10.0-100.0 microg/mL for bergapten, 20.0-200.0 microg/mL for imperatorin, 5.0-400.0 microg/mL for osthole, 10.0-100.0 microg/mL for 2'-acetylangelicin, 10.0-200.0 microg/mL for oroselone, and 10.0-200.0 microg/mL for O-acetylcolumbianetin. The correlation coefficients were between 0.9967 and 0.9995. With this pCEC system, fingerprints of F. cnidii extracts were preliminarily established to distinguish three types of coumarins by characteristic peaks, and the quality of various sources of raw materials was evaluated by determining the contents of six coumarins.
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Affiliation(s)
- Danxia Chen
- Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, No. 325 Guohe Road, Shanghai 200433, PR China
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Tanret I, Mangelings D, Vander Heyden Y. Pressure-assisted CEC versus CEC using methacrylate-based monolithic columns: influence of the polymerization-mixture composition. Electrophoresis 2009; 29:4463-74. [PMID: 19035401 DOI: 10.1002/elps.200800296] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Pressure-assisted CEC (pCEC) can either be performed on a CE instrument by adding pressure at the column inlet, or by applying voltage on a capillary liquid chromatography system. This study investigates the pressure's added value in pCEC using an LC instrument as well as the influence of the polymerization-mixture composition on monolithic columns in such experimental circumstances. Two factors of the polymerization mixture, which is used to prepare the monolithic capillary columns, were varied according to an experimental design approach: the pore-forming solvent/total monomer ratio and the pore-forming solvents composition. Initially, the effect of the resulting stationary phase on the elution behavior of mainly pharmaceutical compounds was studied. Four responses were used to evaluate the effects on the chromatography: retention time, retention factor, peak asymmetry and number of theoretical plates. After processing the results, the stationary phase composition with the best chromatographic behavior was determined and tested. The advantageous properties of this stationary phase compared with the design center-point column were demonstrated. Secondly, the results of these pCEC experiments were compared with those generated in an identical experimental setup previously performed using CEC. Chromatographic conditions were chosen so that the center-point column showed similar retention in CEC and pCEC. The expected advantage (faster analysis) and drawback (decreased efficiency) of pCEC in the analysis of pharmaceuticals was evaluated. Analysis time and efficiency were both found to depend greatly on the porosity of the column. The conclusion of this comparison is that pCEC did not have a significant added value to CEC. However, this was mainly due to the instrument's limitation of the pressure-driven flow over the column. A clear benefit of the pCEC setup was apparatus-related, i.e. the presence of a loop injection system on the pCEC instrument, which avoids the injection problems that were occasionally observed in CEC.
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Affiliation(s)
- Indiana Tanret
- Department of Analytical Chemistry and Pharmaceutical Technology, Pharmaceutical Institute, Vrije Universiteit Brussel-VUB, Brussels, Belgium
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Li H, Liu X, Niu W, Zhu S, Fan L, Shi L, Xu G. CEC with tris(2,2′-bipyridyl) ruthenium(II) electrochemiluminescent detection. Electrophoresis 2008; 29:4475-81. [DOI: 10.1002/elps.200800088] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Ding GS, Tang AN. Capillary electrochromatographic separation of racemates on a norvancomycin-bonded monolithic column under reversed-phase conditions. J Chromatogr A 2008; 1208:232-8. [DOI: 10.1016/j.chroma.2008.08.075] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Revised: 08/21/2008] [Accepted: 08/21/2008] [Indexed: 11/30/2022]
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Tanret I, Mangelings D, Vander Heyden Y. Influence of the polymerization-mixture composition for monolithic methacrylate-based columns on the electrochromatographic performance of drug molecules. J Pharm Biomed Anal 2008; 48:264-77. [DOI: 10.1016/j.jpba.2007.11.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 11/16/2007] [Accepted: 11/20/2007] [Indexed: 11/28/2022]
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Rocco A, Fanali S. Capillary electrochromatography without external pressure assistance. J Chromatogr A 2008; 1191:263-7. [DOI: 10.1016/j.chroma.2007.09.059] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 09/21/2007] [Accepted: 09/25/2007] [Indexed: 10/22/2022]
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Development of capillary electrochromatography with poly(styrene-divinylbenzene-vinylbenzenesulfonic acid) monolith as the stationary phase. J Chromatogr A 2008; 1190:263-70. [PMID: 18358481 DOI: 10.1016/j.chroma.2008.02.105] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 02/17/2008] [Accepted: 02/29/2008] [Indexed: 10/22/2022]
Abstract
A new polystyrene-based monolithic stationary phase, which was prepared by single step in situ copolymerization of styrene, divinylbenzene and vinylbenzenesulfonic acid (VBSA), was developed as a separation column for capillary electrochromatography, in which VBSA was employed as the charge-bearing monomer. Polymerization time of the polystyrene-based monolith had slightly influenced the separation time of the tested analytes, but it effectively altered their separation resolutions. Furthermore, baseline separation for a wider range of acetonitrile levels of mobile phase was achieved when a monolithic column prepared by a longer polymerization time was used. This novel polystyrene-based monolithic column provided an adequate electroosmotic flow either in basic or acidic mobile phase when VBSA level was maintained at 2.6% (w/w). Finally, this proposed polystyrene-based column allowed seven tested analytes to achieve a reproducible baseline separation within 2.2 min with theoretical plate numbers higher than 164 000 plates/m.
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Dulay MT, Choi HN, Zare RN. Visible light-induced photopolymerization of an in situ macroporous sol-gel monolith. J Sep Sci 2008; 30:2979-85. [PMID: 17960846 DOI: 10.1002/jssc.200700328] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A one-step, in situ, photopolymerization of a mixture of methacryloxypropyltrimethoxysilane in the presence of an acid catalyst, water, and toluene is accomplished in a 75 microm id polyimide-coated capillary using visible light (460 nm) for a 15 min irradiation time. The mixture is a two-component photosystem comprising Irgacure 784 photosensitizer and diphenyliodonium chloride photoinitiator. The visible photopolymerized sol-gel (vis-PSG) column shows RP chromatographic behavior. The analytical potential of these columns is demonstrated with the isocratic separation of small, neutral alkyl phenyl ketones. Operational parameters, such as mobile phase composition, field strength, and column temperature were varied to assess how they affect the separation performance of the monolith.
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Affiliation(s)
- Maria T Dulay
- Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA
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Kučerová Z, Szumski M, Buszewski B, Jandera P. Alkylated poly(styrene-divinylbenzene) monolithic columns for μ-HPLC and CEC separation of phenolic acids. J Sep Sci 2007; 30:3018-26. [DOI: 10.1002/jssc.200700346] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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41
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Adalid AM, Herrero-Martínez JM, Roselló S, Maquieira A, Nuez F. Fast determination of prominent carotenoids in tomato fruits by CEC using methacrylate ester-based monolithic columns. Electrophoresis 2007; 28:4120-7. [DOI: 10.1002/elps.200600775] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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42
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Lin J, Wu X, Lin X, Xie Z. Preparation of polymethacrylate monolithic stationary phases having bonded octadecyl ligands and sulfonate groups: electrochromatographic characterization and application to the separation of polar solutes for pressurized capillary electrochromatography. J Chromatogr A 2007; 1169:220-7. [PMID: 17875313 DOI: 10.1016/j.chroma.2007.08.061] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Revised: 08/26/2007] [Accepted: 08/30/2007] [Indexed: 10/22/2022]
Abstract
In this report, the preparation of porous polymethacrylate-based monolithic columns by in situ copolymerization of octadecyl methacrylate (OMA), 3-sulfopropyl methacrylate (SPMA) and ethylene dimethacrylate (EDMA) in a binary porogenic solvent consisting of cyclohexanol/1,4-butanediol are proposed. These monoliths possess in their structures bonded octadecyl ligands and sulfonate groups and are evaluated in pressurized capillary electrochromatography (pCEC) system using small neutral and charged solutes. While the sulfonate groups are meant to generate the electroosmotic flow (EOF) necessary for transporting the mobile phase through the monolithic capillary; the octadecyl ligands are introduced to provide the nonpolar sites for chromatographic retention for neutral solutes. However, incorporating the sulfonate groups in the monoliths does not only support the EOF but also exhibit hydrophilic interaction as well as electrostatic interaction/repulsion with the monoliths in addition to electrophoretic migration with polar charged solutes (e.g., nucleotides). The monolithic stationary phases at different EOF velocities are easily prepared by altering the amount of SPMA in the polymerization solution as well as the composition of the porogenic solvent. Optimum EOF velocity, the highest efficiency and adequate chromatographic retention are obtained when 0.6% SPMA is added to the reaction mixture. Under these conditions, rapid separation and high plate counts reaching greater than 170,000 plates/m are readily obtained.
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Affiliation(s)
- Jian Lin
- Department of Chemistry, Fuzhou University, Fuzhou 350002, China
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43
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Mistry K, Grinberg N. Separation of Peptides and Proteins by Capillary Electrochromatography. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120030601] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Kavita Mistry
- a Analytical Research , Merck & Co., Inc. , RY818‐C208, P.O. Box 2000, Rahway , New Jersey , 07065 , USA
| | - Nelu Grinberg
- a Analytical Research , Merck & Co., Inc. , RY818‐C208, P.O. Box 2000, Rahway , New Jersey , 07065 , USA
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Yang Y, Yan S, Lin Z, Zhang W, Shi Q. Separation and Determination of Major Bioactive Components in Radix Tinosporae by Gradient Pressurized Capillary Electrochromatography. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070701560546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Yun Yang
- a School of Pharmacy, Shanghai Jiaotong University , Shanghai, P. R. China
| | - Shi‐kai Yan
- a School of Pharmacy, Shanghai Jiaotong University , Shanghai, P. R. China
| | - Zhong‐ying Lin
- a School of Pharmacy, Shanghai Jiaotong University , Shanghai, P. R. China
| | - Wei‐dong Zhang
- a School of Pharmacy, Shanghai Jiaotong University , Shanghai, P. R. China
| | - Qi‐rong Shi
- b School of Pharmacy, Second Military Medical University , Shanghai, P. R. China
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45
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Wang Y, Zhang Z, Zhang L, Li F, Chen L, Wan QH. Magnetically immobilized beds for capillary electrochromatography. Anal Chem 2007; 79:5082-6. [PMID: 17539602 DOI: 10.1021/ac070288b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fritless packed beds comprised of magnetically responsive octadecylsilane bonded silica particles have been constructed for reversed-phase electrochromatography. The magnetic particles were immobilized in the capillary by applying an external magnetic field transverse to the direction of electroosmotic flow. Being subjected to the interplay of fluid dragging and magnetic forces, the initial loosely packed particle assembly was compacted into a uniform packing structure. The magnetically immobilized beds obtained were used as stationary phases for separation of neutral compounds, with retention behavior and column efficiency similar to those of slurry-packed columns. The results suggest that the magnetic attraction approach to fritless column packing may be used for construction of advanced chip-based chromatography, especially in complex architectures comprising curved and intersecting channels.
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Affiliation(s)
- Yucong Wang
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
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46
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Anspach JA, Maloney TD, Colón LA. Ultrahigh-pressure liquid chromatography using a 1-mm id column packed with 1.5-μm porous particles. J Sep Sci 2007; 30:1207-13. [PMID: 17595956 DOI: 10.1002/jssc.200600535] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The evolution of chromatography has led to the reduction in the size of the packing materials used to fabricate HPLC columns. The increase in the backpressure required has led to this technique being referred to as ultrahigh-pressure liquid chromatography (UHPLC) when the column backpressure exceeds 10000 psi (approximately 700 bar). Until recently, columns packed with sub-2-microm materials have generally fitted into two classes; either short (less than 5 cm) columns designed for use on traditional HPLC systems at pressures less than 5000 psi (350 bar), or capillary columns (inner diameters less than 100 microm). By using packing materials with diameters <2 microm to fabricate UHPLC columns, there is an increase in efficiency and a decrease in the analysis time that are directly proportional to the size of the packing material. In order to realize and exploit the increase in efficiency, however, the columns must maintain lengths typically associated with analytical columns (15-25 cm). We have packed 1 mm diameter, 150 mm in length columns with 1.5 microm packing material, and evaluated their performance in UHPLC. The pressure required to achieve optimum linear velocities in plots of plate height versus linear velocity was in the vicinity of 1104 bar (16000 psi). The 1.5 microm particle-packed column was compared with the more traditional 150 mm long analytical columns packed with 3 microm materials. This column showed an efficiency that was approximately twice that observed with the 3 microm packed column and a concomitant reduction in the analysis time, theoretically predicted.
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Affiliation(s)
- Jason A Anspach
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260-3000, USA
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47
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Guerrouache M, Carbonnier B, Vidal-Madjar C, Millot MC. In situ functionalization of N-acryloxysuccinimide-based monolith for reversed-phase electrochromatography. J Chromatogr A 2007; 1149:368-76. [PMID: 17416383 DOI: 10.1016/j.chroma.2007.03.039] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 02/23/2007] [Accepted: 03/05/2007] [Indexed: 11/22/2022]
Abstract
Capillary electrochromatography (CEC) monolithic columns were prepared following a two-step synthetic pathway based on (i) UV-induced in situ radical polymerization of N-acryloxysuccinimide (NAS) and ethylene dimethacrylate (EDMA) and (ii) in situ functionalization of the NAS-containing monolithic matrix with various alkylamines. The first synthetic step was performed using toluene as a porogenic solvent. The successful grafting of the alkylamines onto the reactive matrix was confirmed on the basis of qualitative analysis of Raman spectra recorded before and after the chemical modification step. All the electrochromatographic results indicate a strong dependence of the retention, efficiency and selectivity of the monolithic columns on small variations of mobile phase composition and nature of the grafted aliphatic selector in agreement with the typical reversed-phase behaviour. Van Deemter plots for a series of alkylbenzene homologues injected on a column bearing hexyl-segments as side chains are also presented.
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Affiliation(s)
- Mohamed Guerrouache
- Laboratoire de Recherche sur les Polymères, CNRS-Université Paris 12, 2 rue Henri Dunant, 94320 Thiais, France
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Debowski JK. SELECTED APPLICATIONS OF CAPILLARY ELECTROCHROMATOGRAPHY IN THE PHARMACEUTICAL INDUSTRY: TO BUY OR NOT TO BUY? J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120013988] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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49
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Okamoto Y, Ikawa Y, Kitagawa F, Otsuka K. Preparation of fritless capillary using avidin immobilized magnetic particles for electrochromatographic chiral separation. J Chromatogr A 2007; 1143:264-9. [PMID: 17240386 DOI: 10.1016/j.chroma.2007.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 12/26/2006] [Accepted: 01/02/2007] [Indexed: 10/23/2022]
Abstract
In capillary electrochromatography (CEC), magnetic particles (MPs) were packed in a fused silica capillary by using the magnetic field to be retained without frits. For a chiral CEC separation, avidin was immobilized onto the surface of the MPs (AVI-MPs) as a stationary phase by using the physical adsorption technique. The injected AVI-MPs into the capillary were stably captured with the magnet (surface magnetic flux density, 250 mT) under the separation voltage of 10 kV (190 V/cm). By employing the fritless AVI-MPs packed capillary, the chiral separation of ketoprofen was successfully attained with the packing length of only 5 cm. Effects of the modification condition of avidin, pH of background solution, and the packing length on the enantioseparation were also investigated. Under the optimal condition, furthermore, the repeatability for the retention time of ketoprofen was better than 1.5% in the relative standard deviation and the capillary-to-capillary reproducibility was also acceptable in the prepared fritless capillaries.
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Affiliation(s)
- Yukihiro Okamoto
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
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Eeltink S, Svec F. Recent advances in the control of morphology and surface chemistry of porous polymer-based monolithic stationary phases and their application in CEC. Electrophoresis 2007; 28:137-47. [PMID: 17149783 DOI: 10.1002/elps.200600573] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This review focuses on developments in the field of polymer-based monolithic columns for CEC published in the literature since the beginning of the year 2005. The possibility of in-situ preparation as well as easy control over their porous properties and surface chemistries clearly make monolithic separation media an attractive alternative to capillary columns packed with particles. Different variables such as polymerization conditions, morphology, and surface chemistry are shown to directly affect performance of monolithic capillary columns in terms of efficiency, analysis time, and retention.
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Affiliation(s)
- Sebastiaan Eeltink
- Department of Chemistry, University of California, Berkeley, CA 94720-1460, USA
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