The Experts below are selected from a list of 42867 Experts worldwide ranked by ideXlab platform
Vladislav Dolník - One of the best experts on this subject based on the ideXlab platform.
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Capillary Electrophoresis of proteins 2005 2007
Electrophoresis, 2008Co-Authors: Vladislav DolníkAbstract:This review article with 239 references describes recent developments in Capillary Electrophoresis of proteins, and covers the two years since the previous review (V. Dolnik, Electrophoresis 2006, 27, 126-141) through spring 2007. It includes topics related to CE of proteins, such as sample pretreatment, wall coatings, improving separation, various forms of detection, and special electrophoretic techniques including ACE, CIEF, Capillary ITP, and CEC. The paper describes applications of CE to analysis of proteins in real-world samples including human body fluids, food and agricultural samples, protein pharmaceuticals and recombinant protein preparations.
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wall coating for Capillary Electrophoresis on microchips
Electrophoresis, 2004Co-Authors: Vladislav DolníkAbstract:This review article with 116 references describes recent developments in the preparation of wall coatings for Capillary Electrophoresis (CE) on a microchip. It deals with both dynamic and permanent coatings and concentrates on the most frequently used microchip materials including glass, poly(methyl methacrylate), poly(dimethyl siloxane), polycarbonate, and poly(ethylene terephthalate glycol). Characterization of the channel surface by measuring electroosmotic mobility and water contact angle of the surface is included as well. The utility of the microchips with coated channels is demonstrated by examples of CE separations on these chips.
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Polymer wall coatings for Capillary Electrophoresis
Electrophoresis, 2001Co-Authors: Judit Horvath, Vladislav DolníkAbstract:This review article describes the preparation of dynamic and static polymeric wall coatings for Capillary Electrophoresis. Properties of bare fused-silica surfaces and methods for the characterization of Capillary coatings are summarized. The preparation and basic properties of neutral and charged wall coatings are considered. Finally, advantages and potential applications of various coatings are discussed.
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Capillary Electrophoresis on microchip
Electrophoresis, 2000Co-Authors: Vladislav Dolník, Shaorong Liu, Stevan JovanovichAbstract:Capillary Electrophoresis and related techniques on microchips have made great strides in recent years. This review concentrates on progress in Capillary zone Electrophoresis, but also covers other Capillary techniques such as isoelectric focusing, isotachophoresis, free flow Electrophoresis, and micellar electrokinetic chromatography. The material and technologies used to prepare microchips, microchip designs, channel geometries, sample manipulation and derivatization, detection, and applications of Capillary Electrophoresis to microchips are discussed. The progress in separation of nucleic acids and proteins is particularly emphasized.
Niels H H Heegaard - One of the best experts on this subject based on the ideXlab platform.
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Capillary Electrophoresis frontal analysis principles and applications for the study of drug plasma protein binding
Electrophoresis, 2003Co-Authors: Jesper Ostergaard, Niels H H HeegaardAbstract:Capillary Electrophoresis is a well-established technique for the study of noncovalent interactions. Various approaches exist and Capillary Electrophoresis-frontal analysis provides an interesting alternative to the migration shift affinity Capillary Electrophoresis methods and conventional methods. The present work reviews the principles on which the frontal analysis method is founded. Advantages and limitations of Capillary Electrophoresis frontal analysis in comparison with both conventional and other Capillary Electrophoresis based methods for quantification of binding interactions are discussed. Investigations utilizing Capillary Electrophoresis-frontal analysis have focused on the interaction of drugs with plasma proteins. These studies, primarily addressing the binding of drugs to human serum albumin, α1-acid glycoprotein, and lipoproteins are reviewed together with some recent developments in Capillary Electrophoresis-frontal analysis methodology.
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applications of on line weak affinity interactions in free solution Capillary Electrophoresis
Electrophoresis, 2002Co-Authors: Niels H H Heegaard, Mogens Holst Nissen, David D. Y. ChenAbstract:The impressive selectivity offered by Capillary Electrophoresis can in some cases be further increased when ligands or additives that engage in weak affinity interactions with one or more of the separated analytes are added to the Electrophoresis buffer. This on-line affinity Capillary Electrophoresis approach is feasible when the migration of complexed molecules is different from the migration of free molecules and when separation conditions are nondenaturing. In this review, we focus on applying weak interactions as tools to enhance the separation of closely related molecules, e.g., drug enantiomers and on using Capillary Electrophoresis to characterize such interactions quantitatively. We describe the equations for binding isotherms, illustrate how selectivity can be manipulated by varying the additive concentrations, and show how the methods may be used to estimate binding constants. On-line affinity Capillary Electrophoresis methods are especially valuable for enantiomeric separations and for functional characterization of the contents of biological samples that are only available in minute quantities.
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affinity Capillary Electrophoresis important application areas and some recent developments
Journal of Chromatography B: Biomedical Sciences and Applications, 1998Co-Authors: Niels H H Heegaard, Staffan Nilsson, Norberto A GuzmanAbstract:Affinity Capillary Electrophoresis (ACE) is a broad term referring to the separation by Capillary Electrophoresis of substances that participate in specific or non-specific affinity interactions during Electrophoresis. The interacting molecules can be found free in solution or can be immobilized to a solid support. Every ACE mode has advantages and disadvantages. Each can be used for a wide variety of applications. This paper focuses on applications that include purification and concentration of analytes present in diluted solutions or complex matrices, quantitation of analytes based on calibration curves, and estimation of binding constants from direct and derived binding curves based on quantitation of analytes or on analyte migration shifts. A more recent chemicoaffinity strategy in Capillary Electrophoresis/Capillary electrochromatography (CE/CEC) termed molecular imprinting ('plastic antibodies') is discussed as well. Although most ACE studies are aimed at characterizing small-molecular mass analytes such as drugs, hormones, and peptides, some efforts have been pursued to characterize larger biopolymers including proteins, such as immunoglobulins. Examples of affinity interactions that have been studied are antigen-antibody, hapten-antibody, lectin-sugar, drug-protein, and enzyme-substrate complexes using ultraviolet, laser-induced fluorescence, and mass spectrometer detectors. This paper also addresses the critical issue of background electrolyte selection and quantitation of analytes. Specific examples of bioaffinity applications are presented, and the future of ACE in the biomedical field is discussed.
Herve Cottet - One of the best experts on this subject based on the ideXlab platform.
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analysis of glycated hemoglobin a1c by Capillary Electrophoresis and Capillary isoelectric focusing
Analytical Biochemistry, 2011Co-Authors: Dusan Koval, Vaclav Kasicka, Herve CottetAbstract:Two Capillary electrophoretic methods were developed and evaluated for measurement of glycated hemoglobin A1c (HbA1c). First, a Capillary Electrophoresis analysis is performed with a sodium tetraborate buffer (pH 9.3) as background electrolyte in a neutrally coated Capillary. HbA1c is separated from HbA0 due to specific interactions of borate anions with the cis–diol pattern in the saccharide moiety of glycohemoglobin. Second, a Capillary isoelectric focusing method, which exploits a difference in pI values of HbA0 and HbA1c, is performed with Servalyt pH 6–8 or alternatively with Biolyte pH 6–8 carrier ampholytes spiked with a narrow pH cut of pH 7.2 prepared by preparative fractionation of Servalyt pH 4–9 carrier ampholytes. Both methods reflect recent developments in the methodology of Capillary Electrophoresis. They allow quantifying HbA1c in generic Capillary Electrophoresis analyzer with specificity that is consistent with previously reported electrophoretic assays in slab gels and capillaries.
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nonaqueous and aqueous Capillary Electrophoresis of synthetic polymers
Journal of Chromatography A, 2005Co-Authors: Herve Cottet, Carolina Simo, Willy Vayaboury, Alejandro CifuentesAbstract:In this work, the use of Capillary Electrophoresis (CE) to analyze synthetic polymers is reviewed including works published till February 2004. The revised works have been classified depending on the CE mode (e.g., free solution Capillary Electrophoresis, Capillary gel Electrophoresis, etc.) and type of buffer (i.e., nonaqueous, aqueous and hydro-organic background electrolytes) employed to separate synthetic macromolecules. Advantages and drawbacks of these different separation procedures for polymer analysis are discussed. Also, physicochemical studies of complex polymer systems by CE are reviewed, including drug release studies, synthetic polyampholytes, dendrimers, fullerenes, carbon nanotubes and associative copolymers.
Tomoyoshi Soga - One of the best experts on this subject based on the ideXlab platform.
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metabolome analysis by Capillary Electrophoresis mass spectrometry
Journal of Chromatography A, 2007Co-Authors: Maria Rowena N Monton, Tomoyoshi SogaAbstract:Capillary Electrophoresis (CE)-mass spectrometry (MS), as an analytical platform, has made significant contributions in advancing metabolomics research, if still limited up to this time. This review, covering reports published between 1998 and 2006, describes how CE-MS has been used thus far in this field, with the majority of the works dealing with targeted metabolite analyses and only a small fraction using it in the comprehensive context. It also discusses how some of the key features of CE-MS were exploited in selected metabolomic applications.
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simultaneous determination of the main metabolites in rice leaves using Capillary Electrophoresis mass spectrometry and Capillary Electrophoresis diode array detection
Plant Journal, 2004Co-Authors: Shigeru Sato, Tomoyoshi Soga, Takaaki Nishioka, Masaru TomitaAbstract:The study of the metabolomics of primary metabolites using conventional chemical analyses requires a high-throughput method. Chemical derivatizations are a prerequisite for gas-chromatographic separation, and a large sample quantity is needed for liquid-chromatographic separation and nuclear magnetic resonance detection systems. Recently, we have developed a Capillary Electrophoresis-mass spectrometry (CE-MS) technology that can simultaneously quantify a large number of primary metabolites, using only a small quantity of samples, and without any chemical derivatizations. Parallel use of a Capillary Electrophoresis-diode array detector (CE-DAD) system further enables almost all water-soluble intracellular metabolites to be analyzed. We demonstrate, with rice leaves, a simple and rapid method of sample preparation for CE analysis; using this method, we have successfully measured the levels of 88 main metabolites involved in glycolysis, the tricarboxylic acid cycle, the pentose phosphate pathway, photorespiration, and amino acid biosynthesis.
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quantitative metabolome analysis using Capillary Electrophoresis mass spectrometry
Journal of Proteome Research, 2003Co-Authors: Tomoyoshi Soga, Yoshiaki Ohashi, Yuki Ueno, Hisako Naraoka, Masaru Tomita, Takaaki NishiokaAbstract:A new approach for the comprehensive and quantitative analysis of charged metabolites by Capillary Electrophoresis mass spectrometry (CE−MS) is proposed. Metabolites are first separated by CE based...
Frank A Gomez - One of the best experts on this subject based on the ideXlab platform.
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recent advances in affinity Capillary Electrophoresis 2007
Journal of Pharmaceutical Sciences, 2009Co-Authors: Xiaojun Liu, Froseen Dahdouh, Marisol Salgado, Frank A GomezAbstract:Papers detailing the use of affinity Capillary Electrophoresis (ACE) in examining binding parameters between biological species are summarized in this review. The works cited in this review were published during 2007 and were drawn from the major chemical and biochemical journals and especially the major analytical chemistry literature.
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chemometric experimental design based optimization techniques in Capillary Electrophoresis a critical review of modern applications
Analytical and Bioanalytical Chemistry, 2008Co-Authors: Ruthy Montes, Grady Hanrahan, Frank A GomezAbstract:A critical review of recent developments in the use of chemometric experimental design based optimization techniques in Capillary Electrophoresis applications is presented. Current advances have led to enhanced separation capabilities of a wide range of analytes in such areas as biological, environmental, food technology, pharmaceutical, and medical analysis. Significant developments in design, detection methodology and applications from the last 5 years (2002-2007) are reported. Furthermore, future perspectives in the use of chemometric methodology in Capillary Electrophoresis are considered.
