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Caslavska J, Thormann W. Contemporary chiral simulators for capillary zone electrophoresis. Electrophoresis 2019; 41:502-513. [PMID: 31702052 DOI: 10.1002/elps.201900363] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/25/2019] [Accepted: 11/01/2019] [Indexed: 11/09/2022]
Abstract
For separation of enantiomers in presence of a chiral selector, data obtained with the 1D dynamic simulators SIMUL5complex and GENTRANS are compared to data predicted by PeakMaster 6, a recently released generalized model of the linear theory of electromigration. Four electrophoretic systems with stereoisomers of weak bases were investigated. They deal with the estimation of input data for complexation together with the elucidation of the origin of observed system peaks, the interference of analyte and system peak migration, the change of enantiomer migration order as function of the selector concentration and the inversion of analyte migration direction in presence of a multiply negatively charged selector. For all systems, data predicted with PeakMaster 6 are in agreement with those of the dynamic simulators and simulation data compare well with experimental data that were monitored with setups featuring conductivity and/or UV absorbance detection along the capillary. SIMUL5complex and GENTRANS provide the full dynamics of any buffer and sample arrangement and require very long execution time intervals. PeakMaster 6 is restricted to conventional CZE, is based on an approximate solution of the transport equations, provides data for realistic experimental conditions within seconds and represents a practical tool for an experimentalist.
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Affiliation(s)
- Jitka Caslavska
- Clinical Pharmacology Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Wolfgang Thormann
- Clinical Pharmacology Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
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2
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Baron D, Cacho C, Petr J. Electrokinetic preconcentration of magnetite core – carboxylic shell nanoparticles by capillary electrophoresis. J Chromatogr A 2017; 1499:217-221. [DOI: 10.1016/j.chroma.2017.03.079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 12/18/2022]
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3
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Incorporation of polyamidoamine sweeping and electrokinetic supercharging for in-line DNA fragment preconcentration. J Chromatogr A 2013; 1280:112-6. [DOI: 10.1016/j.chroma.2013.01.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 12/28/2012] [Accepted: 01/08/2013] [Indexed: 11/23/2022]
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4
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Separation of ketoprofen enantiomers at nanomolar concentration levels by micellar electrokinetic chromatography with on-line electrokinetic preconcentration. OPEN CHEM 2013. [DOI: 10.2478/s11532-012-0177-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractAbstract Separation of enantiomers represents an extremely important task in the field of analytical chemistry. This paper contributes to the field of the on-line preconcentration of enantiomers by developing a novel setup based on the electrokinetic accumulation of ketoprofen enantiomers on the pH boundary followed by enantioselective mobilization by a mixture of SDS, sulfated-β-cyclodextrin (S-β-CD), and trimethyl-β-cyclodextrin (TM-β-CD). Under the best conditions, where the injection electrolyte was composed of 50 mmol L−1 borate/NaOH pH 9.5 with 60% (v/v) methanol, the background electrolyte contained 50 mmol L−1 phosphate/NaOH pH 2.5, and the mobilization electrolyte consisted of 50 mmol L−1 phosphate/NaOH pH 2.5 with 4.0% (w/v) S-β-CD, 0.5% (w/v) TM-β-CD, and 20 mmol L−1 SDS, the determination of nanomolar concentration levels of ketoprofen enantiomers was successful by using micellar electrokinetic chromatography with a common UV detection. LODs were 2.5 nmol L−1 and 3.4 nmol L−1, which represent enhancement factors of 9921 and 8529, respectively. The method was also applied to the determination of ketoprofen enantiomers in waste water samples by using simple filtration as a clean-up step. Here, the recovery of ketoprofen enantiomers was 91% at the concentration level of 5×10−9 mol L−1. Graphical abstract
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Maijó I, Borrull F, Aguilar C, Calull M. Different strategies for the preconcentration and separation of parabens by capillary electrophoresis. Electrophoresis 2013; 34:363-73. [DOI: 10.1002/elps.201200147] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 09/14/2012] [Accepted: 09/15/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Irene Maijó
- Department of Analytical Chemistry and Organic Chemistry; Faculty of Chemistry; Rovira i Virgili University; Tarragona; Spain
| | - Francesc Borrull
- Department of Analytical Chemistry and Organic Chemistry; Faculty of Chemistry; Rovira i Virgili University; Tarragona; Spain
| | - Carme Aguilar
- Department of Analytical Chemistry and Organic Chemistry; Faculty of Chemistry; Rovira i Virgili University; Tarragona; Spain
| | - Marta Calull
- Department of Analytical Chemistry and Organic Chemistry; Faculty of Chemistry; Rovira i Virgili University; Tarragona; Spain
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6
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Oukacine F, Quirino JP, Destoumieux-Garzón D, Cottet H. Field enhanced bacterial sample stacking in isotachophoresis using wide-bore capillaries. J Chromatogr A 2012; 1268:180-4. [DOI: 10.1016/j.chroma.2012.10.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 10/08/2012] [Accepted: 10/09/2012] [Indexed: 12/12/2022]
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7
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Breadmore MC, Kwan HY, Caslavska J, Thormann W. Dynamic high-resolution computer simulation of electrophoretic enantiomer separations with neutral cyclodextrins as chiral selectors. Electrophoresis 2012; 33:958-69. [DOI: 10.1002/elps.201100472] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Michael C. Breadmore
- Australian Centre for Research on Separation Science,; School of Chemistry; University of Tasmania; Hobart; Tasmania; Australia
| | - Hiu Ying Kwan
- Department of Clinical Pharmacology and Visceral Research; University of Bern; Bern; Switzerland
| | - Jitka Caslavska
- Department of Clinical Pharmacology and Visceral Research; University of Bern; Bern; Switzerland
| | - Wolfgang Thormann
- Department of Clinical Pharmacology and Visceral Research; University of Bern; Bern; Switzerland
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8
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Online sample pre-concentration via dynamic pH junction in capillary and microchip electrophoresis. J Sep Sci 2011; 34:2800-21. [DOI: 10.1002/jssc.201100414] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Sweeping under controlled electroosmotic flow and micellar electrokinetic chromatography for on-line concentration and determination of trace phlorizin and quercitrin in urine samples. J Pharm Biomed Anal 2011; 56:330-5. [DOI: 10.1016/j.jpba.2011.05.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2011] [Revised: 04/25/2011] [Accepted: 05/15/2011] [Indexed: 11/17/2022]
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10
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Zhang Z, Du X, Li X. Sweeping with Electrokinetic Injection and Analyte Focusing by Micelle Collapse in Two-Dimensional Separation via Integration of Micellar Electrokinetic Chromatography with Capillary Zone Electrophoresis. Anal Chem 2011; 83:1291-9. [DOI: 10.1021/ac102344y] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhaoxiang Zhang
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Xiuzhen Du
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Xuemei Li
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
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Breadmore MC, Dawod M, Quirino JP. Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2008-2010). Electrophoresis 2010; 32:127-48. [PMID: 21171119 DOI: 10.1002/elps.201000412] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 09/15/2010] [Accepted: 09/16/2010] [Indexed: 01/22/2023]
Abstract
Capillary electrophoresis has been alive for over two decades now; yet, its sensitivity is still regarded as being inferior to that of more traditional methods of separation such as HPLC. As such, it is unsurprising that overcoming this issue still generates much scientific interest. This review continues to update this series of reviews, first published in Electrophoresis in 2007, with an update published in 2009 and covers material published through to June 2010. It includes developments in the fields of stacking, covering all methods from field-amplified sample stacking and large volume sample stacking, through to ITP, dynamic pH junction and sweeping. Attention is also given to on-line or in-line extraction methods that have been used for electrophoresis.
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Affiliation(s)
- Michael C Breadmore
- Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, Hobart, TAS, Australia.
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12
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Sugimoto M, Hirayama A, Robert M, Abe S, Soga T, Tomita M. Prediction of metabolite identity from accurate mass, migration time prediction and isotopic pattern information in CE-TOFMS data. Electrophoresis 2010; 31:2311-8. [PMID: 20568260 DOI: 10.1002/elps.200900584] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CE-TOFMS is a powerful method for profiling charged metabolites. However, the limited availability of metabolite standards hinders the process of identifying compounds from detected features in CE-TOFMS data sets. To overcome this problem, we developed a method to identify unknown peaks based on the predicted migration time (t(m)) and accurate m/z values. We developed a predictive model using 375 standard cationic metabolites and support vector regression. The model yielded good correlations between the predicted and measured t(m) (R=0.952 and 0.905 using complete and cross-validation data sets, respectively). Using the trained model, we subsequently predicted the t(m) for 2938 metabolites available from the public databases and assigned tentative identities to noise-filtered features in human urine samples. While 38.9% of the peaks were assigned metabolite names by matching with the standard library alone, the proportion increased to 52.2%. The proposed methodology increases the value of metabolomic data sets obtained from CE-TOFMS profiling.
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Affiliation(s)
- Masahiro Sugimoto
- Institute for Advanced Biosciences, Keio University, Yamagata, Japan.
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13
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Analysis of methotrexate and its eight metabolites in cerebrospinal fluid by solid-phase extraction and triple-stacking capillary electrophoresis. Anal Bioanal Chem 2010; 398:2183-90. [DOI: 10.1007/s00216-010-4152-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Revised: 08/04/2010] [Accepted: 08/19/2010] [Indexed: 11/26/2022]
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14
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Vítková K, Petr J, Maier V, Znaleziona J, Ševčík J. Study of electromigration effects on a pH boundary during the on-line electrokinetic preconcentration by capillary electrophoresis. Electrophoresis 2010; 31:2771-7. [DOI: 10.1002/elps.200900663] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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15
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Thormann W, Breadmore MC, Caslavska J, Mosher RA. Dynamic computer simulations of electrophoresis: A versatile research and teaching tool. Electrophoresis 2010; 31:726-54. [DOI: 10.1002/elps.200900613] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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16
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Petr J, Jiang C, Sevcik J, Tesarova E, Armstrong DW. Sterility testing by CE: a comparison of online preconcentration approaches in capillaries with greater internal diameters. Electrophoresis 2010; 30:3870-6. [PMID: 19847804 DOI: 10.1002/elps.200900299] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Detection of microbial contamination is of critical importance in the medical and the food industry. Rapid tests for the absence or presence of viable microorganisms are in urgent demand. CE is a modern analytical technique that can be adapted for rapid screening of microbial contamination. However, the small dimensions of capillaries allow the introduction of only a small fraction of the sample, which can be problematic when examining large samples. In this article, we examine the possibilities of introducing larger sample volumes using capillaries with greater id together with different stacking techniques. The use of 0.32 mm id capillary and the injection of 60% of the capillary volume led to approximately 120-fold improvement of the injected sample volume over the classical injection 5% of a 0.10-mm id capillary. The setup we described opens new possibilities in sterility testing using CE.
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Affiliation(s)
- Jan Petr
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX 76019-0065, USA
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Mikus P, Maráková K. Advanced CE for chiral analysis of drugs, metabolites, and biomarkers in biological samples. Electrophoresis 2010; 30:2773-802. [PMID: 19653234 DOI: 10.1002/elps.200900173] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An analysis of recent trends indicates that CE can show real advantages over chromatographic methods in ultratrace enantioselective determination of biologically active compounds in complex biological matrices. It is due to high separation efficiency and many applicable in-capillary electromigration effects in CE (countercurrent migration, stacking effects) enhancing significantly (enantio)separability and enabling effective sample preparation (preconcentration, purification, analyte derivatization). Other possible on-line combinations of CE, such as column coupled CE-CE techniques and implementation of nonelectrophoretic techniques (extraction, membrane filtration, flow injection) into CE, offer additional approaches for highly effective sample preparation and separation. CE matured to a highly flexible and compatible technique enabling its hyphenation with powerful detection systems allowing extremely sensitive detection (e.g. LIF) and/or structural characterization of analytes (e.g. MS). Within the last decade, more as well as less conventional analytical on-line approaches have been effectively utilized in this field and their practical potentialities are demonstrated on many new application examples in this article. Here, three basic areas of (enantioselective) drug bioanalysis are highlighted and supported by a brief theoretical description of each individual approach in a compact review structure (to create integrated view on the topic), including (i) progressive enantioseparation approaches and new enantioselective agents, (ii) in-capillary sample preparation (preconcentration, purification, derivatization), and (iii) detection possibilities related to enhanced sensitivity and structural characterization.
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Affiliation(s)
- Peter Mikus
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic.
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Abstract
Sample stacking techniques remain an important tool for enhancement of the selectivity and sensitivity of analyses in contemporary CZE. This contribution reviews new knowledge on this topic published since 2006. It is organized according to the operational principles used, which include concentration adjustment, application of a pH step, MEKC and sweeping, and transient ITP. Techniques combining several of these principles and comparative studies are also included.
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Affiliation(s)
- Zdena Malá
- Institute of Analytical Chemistry of the ASCR, Brno, Czech Republic
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20
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Electrokinetic and hydrodynamic injection: making the right choice for capillary electrophoresis. Bioanalysis 2009; 1:889-94. [DOI: 10.4155/bio.09.73] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Dr Michael Breadmore is an Australian Research Council Queen Elizabeth II fellow with interests in the development of miniaturised analytical systems for the improved ana lysis of drugs and metabolites in biological fluids. He is based at the Australian Center for Research on Separation Science (ACROSS) at the University of Tasmania, Australia. He has spent the last 10 years developing novel electrophoresis methods for a range of applications with a particular interest in new ways to enhance the sensitivity. CE is a powerful liquid-phase separation technique that is an attractive alternative to HPLC because of its small sample requirements, high resolving power and excellent mass detection limits. While there are many similarities between the two techniques, there are also many differences, some obvious, some subtle. One of the often overlooked differences is the way sample is injected. In HPLC, injection is a very minor component of the method and the choice is predominantly restricted to the choice of solvent and the injection volume. But in CE, it is vastly more complex, and development of an appropriate injection strategy should be given consideration during any method development. While the choice between hydrodynamic or electrokinetic injection may not initially be given any thought, selection of the right approach for the right application can lead to significant improvements in performance, particularly with regard to achieving the lowest detection limits possible. The question is how to decide the best way to inject for each application?
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Thormann W, Caslavska J, Breadmore MC, Mosher RA. Dynamic computer simulations of electrophoresis: Three decades of active research. Electrophoresis 2009; 30 Suppl 1:S16-26. [DOI: 10.1002/elps.200900058] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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22
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Zhang Z, Zhang M, Zhang S. Online preconcentration and two‐dimensional separation of cationic compoundsviahyphenation of capillary zone electrophoresis with cyclodextrin‐modified micellar electrokinetic capillary chromatography. Electrophoresis 2009; 30:1958-66. [DOI: 10.1002/elps.200800571] [Citation(s) in RCA: 22] [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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23
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Breadmore MC, Quirino JP, Thormann W. High-resolution computer simulations of EKC. Electrophoresis 2009; 30:570-8. [DOI: 10.1002/elps.200800671] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Hruška V, Gaš B, Vigh G. Simulation of desalting that occurs during isoelectric trapping separations. Electrophoresis 2009; 30:433-43. [DOI: 10.1002/elps.200800372] [Citation(s) in RCA: 12] [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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Breadmore MC, Thabano JRE, Dawod M, Kazarian AA, Quirino JP, Guijt RM. Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2006-2008). Electrophoresis 2009; 30:230-48. [DOI: 10.1002/elps.200800435] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Recent applications of capillary electrophoresis–mass spectrometry (CE–MS): CE performing functions beyond separation. Anal Chim Acta 2008; 627:3-24. [DOI: 10.1016/j.aca.2008.04.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Revised: 04/02/2008] [Accepted: 04/08/2008] [Indexed: 11/18/2022]
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Kazarian AA, Hilder EF, Breadmore MC. Utilisation of pH stacking in conjunction with a highly absorbing chromophore, 5-aminofluorescein, to improve the sensitivity of capillary electrophoresis for carbohydrate analysis. J Chromatogr A 2008; 1200:84-91. [PMID: 18468613 DOI: 10.1016/j.chroma.2008.04.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Revised: 04/09/2008] [Accepted: 04/11/2008] [Indexed: 11/30/2022]
Abstract
This study explores the use of pH stacking in conjunction with 5-aminofluorescein as a derivatization agent for the sensitive analysis of simple sugars such as glucose, lactose and maltotriose by capillary electrophoresis (CE). The derivatization agent was selected on the basis of its extremely high molar absorptivity, its compatibility with a 488nm light-emitting diode (LED) and the fact that it has two ionizable groups making it compatible with on-line stacking using a dynamic pH junction. The influence of both acetic and formic acids at concentrations of 0.19, 0.019 and 0.0019molL(-1) were investigated with regard to both derivatization efficiency and the ability to stack using a dynamic pH junction. Superior sensitivity and resolution was obtained in formic acid over acetic acid. Substantially lower peaks were obtained with 0.19molL(-1) formic acid when compared to 0.019 and 0.0019molL(-1) concentrations, which was confirmed by computer simulation studies to be due to the inadequate movement of the pH boundary for stacking. Further simulation studies combined with experimental data showed the separation with the best resolution and greatest sensitivity when the carbohydrates were derivatized with the 0.095molL(-1) formic acid. Utilisation of stacking via dynamic pH junction mode in conjunction with LED detection enabled efficiencies of 150,000 plates and detection limits in the order of 8.5x10(-8)molL(-1) for simple sugars such as glucose, lactose and maltotriose hydrate. The current system also demonstrates a 515 times improvement in sensitivity when compared to using a normal deuterium lamp, and 16 times improvement over other systems using LEDs.
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Affiliation(s)
- Artaches A Kazarian
- Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia
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Breadmore MC, Quirino JP. 100 000-Fold Concentration of Anions in Capillary Zone Electrophoresis Using Electroosmotic Flow Controlled Counterflow Isotachophoretic Stacking under Field Amplified Conditions. Anal Chem 2008; 80:6373-81. [DOI: 10.1021/ac8007835] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael C. Breadmore
- Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, G.P.O. Box 252-75, Hobart, Tasmania 7001, Australia
| | - Joselito P. Quirino
- Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, G.P.O. Box 252-75, Hobart, Tasmania 7001, Australia
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Petr J, Vítková K, Ranc V, Znaleziona J, Maier V, Knob R, Sevcík J. Determination of some phenolic acids in Majorana hortensis by capillary electrophoresis with online electrokinetic preconcentration. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:3940-3944. [PMID: 18473473 DOI: 10.1021/jf8000179] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
An online accumulation/mobilization preconcentration technique based on a dynamic pH junction technique and electrokinetic injection was employed for analysis of phenolic acids (sinapic, ferulic, coumarinic, caffeic, syringic, vanillic, and 4-hydroxybenzoic acid) in extracts from Majorana hortensis leaves. Samples were extracted by pressurized solvent extraction with acetone at 150 degrees C and 15 MPa. The capillary electrophoretic method employed 50 mmol.L (-1) sodium borate, pH 9.5, as the sample electrolyte, 50 mmol.L (-1) sodium phosphate, pH 2.5, as the background electrolyte, and 50 mmol.L (-1) sodium phosphate, pH 2.5, with 60 mmol.L (-1) sodium dodecyl sulfate as the mobilization electrolyte. The method allowed 720-fold to 5560-fold preconcentration of the phenolic acids during 30 min of electrokinetic accumulation with detection limits from 0.38 to 4.22 ng.mL (-1).
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Affiliation(s)
- Jan Petr
- Department of Analytical Chemistry, Faculty of Science, Palacky University in Olomouc, Trida Svobody 8, Olomouc, Czech Republic.
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Breadmore MC. Unlimited-volume stacking of ions in capillary electrophoresis. Part 1: Stationary isotachophoretic stacking of anions. Electrophoresis 2008; 29:1082-91. [DOI: 10.1002/elps.200700728] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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Ptolemy AS, Britz-McKibbin P. New advances in on-line sample preconcentration by capillary electrophoresis using dynamic pH junction. Analyst 2008; 133:1643-8. [DOI: 10.1039/b808236g] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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