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Witzel MT, Veltri LM, Kostelic M, Elshamy YS, Lucas JA, Lai S, Du C, Wysocki VH, Holland LA. Protein analysis using capillary electrophoresis coupled to mass spectrometry through vibrating sharp-edge spray ionization. Electrophoresis 2024; 45:1597-1605. [PMID: 38577828 PMCID: PMC11438567 DOI: 10.1002/elps.202300298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 03/11/2024] [Accepted: 03/14/2024] [Indexed: 04/06/2024]
Abstract
Capillary electrophoresis (CE) interfaced to mass spectrometry (MS) with electrospray ionization typically incorporates acidic additives or organic solvents to assist in ionization. Vibrating sharp-edge spray ionization (VSSI) is a voltage-free method to interface CE and MS that does not require these additives, making it appealing for protein analyses. CE-VSSI nanoflow sheath separations are performed with low ionic strength aqueous solutions in the sheath to reduce suppression. Serine is also included in the sheath to reduce analyte adduction. Proteins are detected in the 2.5-10 µM range, corresponding to an injected mass range of 0.1-1.2 ng. The anionic proteins β-lactoglobulin and transferrin are resolved using an unmodified fused silica capillary because they do not exhibit nonspecific surface adsorption. Conversely, separations of cationic proteins cytochrome c, ribonuclease A, and α-chymotrypsinogen A in an unmodified capillary require acidic background electrolytes to overcome adsorption. Alternatively, a semipermanent coating comprised self-assembled lipids overcomes surface adsorption at a neutral pH. Separations with zwitterionic and hybrid cationic coatings are complete within 15 or 6 min, respectively. The dimeric form of triosephosphate isomerase was observed at a 60 µM, corresponding to a mass of 19 ng, by dropping the temperature of the MS inlet.
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Affiliation(s)
- Makenzie T Witzel
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, USA
| | - Lindsay M Veltri
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, USA
| | - Marius Kostelic
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio, USA
| | - Yousef S Elshamy
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, USA
| | - John A Lucas
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, USA
| | - Stella Lai
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio, USA
| | - Chen Du
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio, USA
| | - Vicki H Wysocki
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio, USA
| | - Lisa A Holland
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, USA
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2
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Szabó ZI, Benkő BM, Bartalis-Fábián Á, Iványi R, Varga E, Szőcs L, Tóth G. Chiral Separation of Apremilast by Capillary Electrophoresis Using Succinyl-β-Cyclodextrin-Reversal of Enantiomer Elution Order by Cationic Capillary Coating. Molecules 2023; 28:molecules28083310. [PMID: 37110544 PMCID: PMC10143784 DOI: 10.3390/molecules28083310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/03/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
A stereospecific capillary electrophoresis method was developed for the separation of the novel, antipsoriatic agent, apremilast (APR). Six anionic cyclodextrin (CD) derivatives were screened for their ability to discriminate between the uncharged enantiomers. Only succinyl-β-CD (Succ-β-CD) presented chiral interactions; however, the enantiomer migration order (EMO) was unfavorable, and the eutomer, S-APR, migrated faster. Despite the optimization of all possible parameters (pH, cyclodextrin concentration, temperature, and degree of substitution of CD), the method was unsuccessful for purity control due to the low resolution and the unfavorable enantiomer migration order. Changing the direction of electroosmotic flow (EOF) by the dynamic coating of the inner surface of the capillary with poly(diallyldimethylammonium) chloride or polybrene resulted in EMO reversal, and the developed method could be applied for the determination of R-APR as the enantiomeric purity. Thus, the application of the dynamic capillary coating offers a general opportunity for enantiomeric migration order reversal in particular cases when the chiral selector is a weak acid.
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Affiliation(s)
- Zoltán-István Szabó
- Faculy of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, Gh. Marinescu 38, 540139 Târgu Mureș, Romania
- Sz-Imfidum Ltd., nr. 504, 525401 Lunga, Romania
| | - Beáta-Mária Benkő
- University Pharmacy Department of Pharmaceutical Administration, Semmelweis University, Hőgyes E. 9, H-1085 Budapest, Hungary
| | - Ágnes Bartalis-Fábián
- Faculy of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, Gh. Marinescu 38, 540139 Târgu Mureș, Romania
| | - Róbert Iványi
- Cyclolab Ltd., Illatos út 7, H-1097 Budapest, Hungary
| | | | - Levente Szőcs
- Cyclolab Ltd., Illatos út 7, H-1097 Budapest, Hungary
| | - Gergő Tóth
- Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes E. 9, H-1085 Budapest, Hungary
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3
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van der Burg D, Wätzig H, Sänger-van de Griend CE. Method development for quantitative monitoring of monoclonal antibodies in upstream cell-culture process samples with limited sample preparation - An evaluation of various capillary coatings. Electrophoresis 2023; 44:96-106. [PMID: 36239141 PMCID: PMC10099398 DOI: 10.1002/elps.202200144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 11/11/2022]
Abstract
Monoclonal antibodies (mAbs) have become an important class of biopharmaceuticals used for the treatment of various diseases. Their quantification during the manufacturing process is important. In this work, a capillary zone electrophoresis (CZE) method was developed for the monitoring of the mAb concentration during cell-culture processes. CZE method development rules are outlined, particularly discussing various capillary coatings, such as a neutral covalent polyvinyl alcohol coating, a dynamic successive multiple ionic-polymer coating, and dynamic coatings using background electrolyte additives such as triethanolamine (T-EthA) and triethylamine. The dynamic T-EthA coating resulted in most stable electro-osmotic flows and most efficient peak shapes. The method is validated over the range 0.1-10 mg/ml, with a linear range of 0.08-1.3 mg/ml and an extended range of 1-10 mg/ml by diluting samples in the latter concentration range 10-fold in water. The intraday precision and accuracy were 2%-12% and 88%-107%, respectively, and inter-day precision and accuracy were 4%-9% and 93%-104%, respectively. The precision and accuracy of the lowest concentration level (0.08 mg/ml) were slightly worse and still well in scope for monitoring purposes. The presented method proved applicable for analysing in-process cell-culture samples from different cell-culture processes and is possibly well suited as platform method.
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Affiliation(s)
- Debbie van der Burg
- Kantisto BV, Baarn, The Netherlands.,Department of Chemistry, KTH Royal Institute of Technology, Division of Applied Physical Chemistry, Stockholm, Sweden.,Institute of Medicinal and Pharmaceutical Chemistry, Technische Universität Braunschweig, Braunschweig, Germany
| | - Hermann Wätzig
- Institute of Medicinal and Pharmaceutical Chemistry, Technische Universität Braunschweig, Braunschweig, Germany
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4
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Roca S, Dhellemmes L, Leclercq L, Cottet H. Polyelectrolyte Multilayers in Capillary Electrophoresis. Chempluschem 2022; 87:e202200028. [PMID: 35388990 DOI: 10.1002/cplu.202200028] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/19/2022] [Indexed: 02/21/2024]
Abstract
Capillary electrophoresis (CE) has been proven to be a performant analytical method to analyze both small and macro molecules. Indeed, it is capable of separating compounds of the same nature according to differences in their charge to size ratios, particularly proteins, monoclonal antibodies and peptides. However, one of the major obstacles to reach high separation efficiency remains the adsorption of solutes on the capillary wall. Among the different coating approaches used to control and minimize solute adsorption, polyelectrolyte multilayers can be applied to CE as a versatile approach. These coatings are made up of alternating layers of polycations and polyanions, and may be used in acidic, neutral or basic conditions depending on the solutes to be analyzed. This Review provides an overview of Successive Multiple Ionic-polymer Layer (SMIL) coatings used in CE, looking at how different parameters induce variations on the electro-osmotic flow (EOF), separation efficiency and coating stability, as well as their promising applications in the biopharmaceutical field.
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Affiliation(s)
- Sébastien Roca
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
| | - Laura Dhellemmes
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
| | - Laurent Leclercq
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
| | - Hervé Cottet
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
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Gstöttner C, Haselberg R, Wuhrer M, Somsen GW, Domínguez-Vega E. Assessment of Macro- and Microheterogeneity of Monoclonal Antibodies Using Capillary Zone Electrophoresis Hyphenated with Mass Spectrometry. Methods Mol Biol 2022; 2531:125-142. [PMID: 35941483 DOI: 10.1007/978-1-0716-2493-7_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This chapter focuses on the application of capillary zone electrophoresis hyphenated with mass spectrometry (CZE-MS) for the characterization of monoclonal antibodies (mAbs). mAbs are complex molecules comprising different glycoforms and many other posttranslational modifications. In addition to this inherent microheterogeneity, misassembling of antibodies can take place during production contributing to their macroheterogeneity. CZE-MS is a versatile and powerful technique which has demonstrated high potential for the assessment of both micro- and macroheterogeneity of mAbs. In this chapter, technical and practical considerations for the characterization of mAbs by CZE-MS are described. CE-MS interfacing, capillary coatings for the prevention of mAb adsorption, and sample preparation considerations are covered in detail. The assessment of the macro- and microheterogeneity is discussed and exemplified through three different approaches involving analysis of intact, enzymatically digested, and reduced antibodies. The examples also illustrate the use of two commercially available interfacing techniques (i.e., sheath liquid and sheathless) as well as different types of capillary coatings (positively charged and neutral coatings).
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Affiliation(s)
- Christoph Gstöttner
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Rob Haselberg
- Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Govert W Somsen
- Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Elena Domínguez-Vega
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands.
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6
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Suntornsuk L, Anurukvorakun O. Sensitivity enhancement in capillary electrophoresis and their applications for analyses of pharmaceutical and related biochemical substances. Electrophoresis 2021; 43:939-954. [PMID: 34902168 DOI: 10.1002/elps.202100236] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/23/2021] [Accepted: 11/30/2021] [Indexed: 11/11/2022]
Abstract
This review aims to illustrate sensitivity enhancement methods in capillary electrophoresis (CE) and their applications for pharmaceutical and related biochemical substance analyses. The first two parts of the article describe the introduction and principle of CE. The main part focuses on strategies for sensitivity improvement in CE including detector and capillary technologies and pre-concentration techniques. Applications of these techniques for pharmaceutical and biomedical substance analyses are surveyed during the years 2018-2021. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Leena Suntornsuk
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, Bangkok, 10400, Thailand
| | - Oraphan Anurukvorakun
- Department of Cosmetic Science, Phranakorn Rajabhat University, Bangkok, 10220, Thailand
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7
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Hamidli N, Andrasi M, Nagy C, Gaspar A. Analysis of intact proteins with capillary zone electrophoresis coupled to mass spectromery using uncoated and coated capillaries. J Chromatogr A 2021; 1654:462448. [PMID: 34392123 DOI: 10.1016/j.chroma.2021.462448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 07/28/2021] [Accepted: 07/28/2021] [Indexed: 10/20/2022]
Abstract
Although, in general, the application of coated capillaries is recommended for the separation of intact proteins, bare silica capillary is still the most often used capillary due to its simplicity and cheapness. In this work, the performance of bare fused silica capillary for intact protein analysis was compared to that of different (dynamically coated polybrene (PB) and permanently coated linear polyacrylamide (LPA)) coated capillaries using capillary zone electrophoresis - mass spectrometry (CZE-MS). In cases where low pH (pH=1.8) was used in bare silica capillaries, good precision (0.56-0.78 RSD% and 1.7-6.5 RSD% for migration times and peak areas, respectively), minimal adsorption and separation efficiency (N= 27 000/m - 322 000/m) similar to or even better than those obtained with the coated capillaries (created by an intricate multi-step process) was achieved. The PB and the LPA capillaries demonstrated their slightly better resolving power in terms of separating the different forms/variants of the same protein (e.g., hemoglobin subunits). Among the studied capillaries the one with LPA coating showed the most stable separations in the long term (n=25: 0.18-0.49 RSD% and 3.1-4.9 RSD% for migration times and peak areas, respectively). For the separation of a few proteins or even a larger number of proteins in biological samples (e.g., snake venom) the application of the simple and cheap bare fused silica capillary can be considered as an efficient choice.
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Affiliation(s)
- N Hamidli
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, H-4032, Debrecen, Hungary
| | - M Andrasi
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, H-4032, Debrecen, Hungary
| | - C Nagy
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, H-4032, Debrecen, Hungary
| | - A Gaspar
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem ter 1, H-4032, Debrecen, Hungary.
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8
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Novel approach for the synthesis of a neutral and covalently bound capillary coating for capillary electrophoresis-mass spectrometry made from highly polar and pH-persistent N-acryloylamido ethoxyethanol. Anal Bioanal Chem 2019; 412:561-575. [PMID: 31872272 DOI: 10.1007/s00216-019-02286-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/28/2019] [Accepted: 11/14/2019] [Indexed: 10/25/2022]
Abstract
Statically adsorbed or covalently coupled capillary coatings are of crucial importance in capillary electrophoresis-mass spectrometry for the separation of peptides and proteins. So far, published coating strategies and commercially available coated capillaries have a limited pH-stability so that the analysis at strongly acidic pH is limited, or harsh rinsing procedures for biological sample analysis cannot be applied. We here present a capillary coating based on Si-C linkages to N-acryloylamido ethoxyethanol (AAEE) with a new synthetic strategy including LiAlH4 surface reaction. We optimized the coating method with emphasis on stability and reproducibility applying harsh rinsing procedures (strong acid, strong base and organic solvent), using the electroosmotic mobility and separation efficiency of tryptic peptides as performance measure. Complete synthesis is performed in less than 2 days for up to 8 capillaries in parallel of more than 16 m total length. Intra- and inter-batch reproducibility were determined regarding electroosmotic mobility, separation efficiency and migration time precision in CE-MS separations of tryptically digested bovine serum albumin. Coating stability towards rinsing with strong acid (1 mol/L HCl), organic solvent (acetonitrile) and strong base (1 mol/L NaOH) was investigated. Outstanding performance was found for single capillaries. However, inter-capillary reproducibility is discussed critically. The new coating was successfully applied for reproducible CE-MS separation of large proteins in diluted serum, medium-sized peptides and small and highly charged polyamines in fish egg extracts using a very acidic background electrolyte containing 0.75 mol/L acetic acid and 0.25 mol/L formic acid (pH 2.2).
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9
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Gahoual R, Leize-Wagner E, Houzé P, François YN. Revealing the potential of capillary electrophoresis/mass spectrometry: the tipping point. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33 Suppl 1:11-19. [PMID: 30022554 DOI: 10.1002/rcm.8238] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/04/2018] [Accepted: 07/11/2018] [Indexed: 06/08/2023]
Abstract
The hyphenation of capillary electrophoresis and mass spectrometry (CE/MS) remains a minor technique compared with liquid chromatography/mass spectrometry (LC/MS), which represents nowadays the standard instrumentation, regardless of its introduction thirty years ago. However, from a theoretical point of view, CE coupling should be quite favorable especially with electrospray ionization mass spectrometry (ESI-MS). At the time, the sensitivity provided by CE/MS was often limited, due to hyphenation requirements, which at some point appeared to disqualify CE/MS from benefiting from the performance gain driving the evolution of MS instruments. However, this context has been significantly modified in a matter of a few years. The development of innovative CE/MS interfacing systems has enabled an important improvement regarding sensitivity and reinforced robustness in order to provide an instrumentation accessible to the largest scientific community. Because of the unique selectivity delivered by the electrophoretic separation, CE/MS has proved to be particularly relevant for the analysis of biological molecules. The conjunction of these aspects is motivating the interest in CE/MS analysis and shows that CE/MS is mature enough to enrich the toolbox of analytical techniques for the analysis of complex biological samples. Here we discuss the characteristics of the major types of high-sensitivity CE/ESI-MS instrumentation and emphasize the late evolution and future positioning of CE/MS analysis for the characterization of biological molecules like peptides and proteins, through some pertinent applications.
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Affiliation(s)
- Rabah Gahoual
- Unité de Technologies Biologiques et Chimiques pour la Santé (UTCBS), Paris 5-CNRS UMR8258 Inserm U1022, Faculté de Pharmacie, Université Paris Descartes, Paris, France
| | - Emmanuelle Leize-Wagner
- Laboratoire de spectrométrie de masse des interactions et des systèmes (LSMIS), Unistra-CNRS UMR7140, Université de Strasbourg, Strasbourg, France
| | - Pascal Houzé
- Unité de Technologies Biologiques et Chimiques pour la Santé (UTCBS), Paris 5-CNRS UMR8258 Inserm U1022, Faculté de Pharmacie, Université Paris Descartes, Paris, France
- Laboratoire de Biochimie, Hôpital Universitaire Necker-Enfants malades, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Yannis-Nicolas François
- Laboratoire de spectrométrie de masse des interactions et des systèmes (LSMIS), Unistra-CNRS UMR7140, Université de Strasbourg, Strasbourg, France
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10
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Yang X, Bartlett MG. Glycan analysis for protein therapeutics. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1120:29-40. [PMID: 31063953 DOI: 10.1016/j.jchromb.2019.04.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 04/10/2019] [Accepted: 04/15/2019] [Indexed: 01/07/2023]
Abstract
Glycosylation can be a critical quality attribute for protein therapeutics due to its extensive impact on product safety and efficacy. Glycan characterization is important in the process of protein drug development, from early stage candidate selection to late stage regulatory submission. It is also an indispensable part in the evaluation of biosimilarity. This review discusses the effects of glycosylation on the stability and activity of protein therapeutics, regulatory considerations corresponding to manufacturing and structural characterization of glycosylated protein therapeutics, and focuses on mass spectrometry compatible separation methods for glycan characterization of protein therapeutics. These approaches include hydrophilic interaction liquid chromatography, reversed-phase liquid chromatography, capillary electrophoresis, porous graphitic carbon liquid chromatography and two-dimensional liquid chromatography. Advances and novelties in each separation method, as well as associated challenges and limitations, are discussed at the released glycan, glycopeptide, glycoprotein subunit and intact glycoprotein levels.
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Affiliation(s)
- Xiangkun Yang
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA 30602-2352, United States of America
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA 30602-2352, United States of America.
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11
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Astefanei A, Dapic I, Camenzuli M. Different Stationary Phase Selectivities and Morphologies for Intact Protein Separations. Chromatographia 2016; 80:665-687. [PMID: 28529348 PMCID: PMC5413533 DOI: 10.1007/s10337-016-3168-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 08/17/2016] [Accepted: 09/06/2016] [Indexed: 12/18/2022]
Abstract
The central dogma of biology proposed that one gene encodes for one protein. We now know that this does not reflect reality. The human body has approximately 20,000 protein-encoding genes; each of these genes can encode more than one protein. Proteins expressed from a single gene can vary in terms of their post-translational modifications, which often regulate their function within the body. Understanding the proteins within our bodies is a key step in understanding the cause, and perhaps the solution, to disease. This is one of the application areas of proteomics, which is defined as the study of all proteins expressed within an organism at a given point in time. The human proteome is incredibly complex. The complexity of biological samples requires a combination of technologies to achieve high resolution and high sensitivity analysis. Despite the significant advances in mass spectrometry, separation techniques are still essential in this field. Liquid chromatography is an indispensable tool by which low-abundant proteins in complex samples can be enriched and separated. However, advances in chromatography are not as readily adapted in proteomics compared to advances in mass spectrometry. Biologists in this field still favour reversed-phase chromatography with fully porous particles. The purpose of this review is to highlight alternative selectivities and stationary phase morphologies that show potential for application in top-down proteomics; the study of intact proteins.
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Affiliation(s)
- A. Astefanei
- Centre for Analytical Science in Amsterdam (CASA), Van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - I. Dapic
- Centre for Analytical Science in Amsterdam (CASA), Van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - M. Camenzuli
- Centre for Analytical Science in Amsterdam (CASA), Van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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12
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A simple sheathless CE-MS interface with a sub-micrometer electrical contact fracture for sensitive analysis of peptide and protein samples. Anal Chim Acta 2016; 936:157-67. [PMID: 27566351 DOI: 10.1016/j.aca.2016.07.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/28/2016] [Accepted: 07/01/2016] [Indexed: 12/11/2022]
Abstract
Online coupling of capillary electrophoresis (CE) to electrospray ionization mass spectrometry (MS) has shown considerable potential, however, technical challenges have limited its use. In this study, we have developed a simple and sensitive sheathless CE-MS interface based on the novel concept of forming a sub-micrometer fracture directly in the capillary. The simple interface design allowed the generation of a stable ESI spray capable of ionization at low nanoliter flow-rates (45-90 nL/min) for high sensitivity MS analysis of challenging samples like those containing proteins and peptides. By analysis of a model peptide (leucine enkephalin), a limit of detection (LOD) of 0.045 pmol/μL (corresponding to 67 attomol in a sample volume of ∼15 nL) was obtained. The merit of the CE-MS approach was demonstrated by analysis of bovine serum albumin (BSA) tryptic peptides. A well-resolved separation profile was achieved and comparable sequence coverage was obtained by the CE-MS method (73%) compared to a representative UPLC-MS method (77%). The CE-MS interface was subsequently used to analyse a more complex sample of pharmaceutically relevant human proteins including insulin, tissue factor and α-synuclein. Efficient separation and protein ESI mass spectra of adequate quality could be achieved using only a small amount of sample (30 fmol). In addition, analysis of ubiquitin samples under both native and denatured conditions, indicate that the CE-MS setup can facilitate native MS applications to probe the conformational properties of proteins. Thus, the described CE-MS setup should be useful for a wide range of high-sensitivity applications in protein research.
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13
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Leitner M, Stock LG, Traxler L, Leclercq L, Bonazza K, Friedbacher G, Cottet H, Stutz H, Ebner A. Mapping molecular adhesion sites inside SMIL coated capillaries using atomic force microscopy recognition imaging. Anal Chim Acta 2016; 930:39-48. [PMID: 27265903 DOI: 10.1016/j.aca.2016.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 04/29/2016] [Accepted: 05/01/2016] [Indexed: 10/21/2022]
Abstract
Capillary zone electrophoresis (CZE) is a powerful analytical technique for fast and efficient separation of different analytes ranging from small inorganic ions to large proteins. However electrophoretic resolution significantly depends on the coating of the inner capillary surface. High technical efforts like Successive Multiple Ionic Polymer Layer (SMIL) generation have been taken to develop stable coatings with switchable surface charges fulfilling the requirements needed for optimal separation. Although the performance can be easily proven in normalized test runs, characterization of the coating itself remains challenging. Atomic force microscopy (AFM) allows for topographical investigation of biological and analytical relevant surfaces with nanometer resolution and yields information about the surface roughness and homogeneity. Upgrading the scanning tip to a molecular biosensor by adhesive molecules (like partly inverted charged molecules) allows for performing topography and recognition imaging (TREC). As a result, simultaneously acquired sample topography and adhesion maps can be recorded. We optimized this technique for electrophoresis capillaries and investigated the charge distribution of differently composed and treated SMIL coatings. By using the positively charged protein avidin as a single molecule sensor, we compared these SMIL coatings with respect to negative charges, resulting in adhesion maps with nanometer resolution. The capability of TREC as a functional investigation technique at the nanoscale was successfully demonstrated.
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Affiliation(s)
- Michael Leitner
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria
| | - Lorenz G Stock
- Division of Chemistry and Bioanalytics, Department of Molecular Biology, University Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria; Christian Doppler Laboratory for Innovative Tools for the Characterization of Biosimilars, University Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria
| | - Lukas Traxler
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria
| | - Laurent Leclercq
- Institut des Biomolécules Max Mousseron (IBMM, UMR 5247, CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier), Place Eugène Bataillon, CC 1706, 34095 Montpellier, France
| | - Klaus Bonazza
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164, 1060 Vienna, Austria
| | - Gernot Friedbacher
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164, 1060 Vienna, Austria
| | - Hervé Cottet
- Institut des Biomolécules Max Mousseron (IBMM, UMR 5247, CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier), Place Eugène Bataillon, CC 1706, 34095 Montpellier, France
| | - Hanno Stutz
- Division of Chemistry and Bioanalytics, Department of Molecular Biology, University Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria; Christian Doppler Laboratory for Innovative Tools for the Characterization of Biosimilars, University Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria
| | - Andreas Ebner
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria.
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14
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Heemskerk AAM, Deelder AM, Mayboroda OA. CE-ESI-MS for bottom-up proteomics: Advances in separation, interfacing and applications. MASS SPECTROMETRY REVIEWS 2016; 35:259-271. [PMID: 24852088 DOI: 10.1002/mas.21432] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 03/27/2014] [Indexed: 06/03/2023]
Abstract
With the development of more sensitive hyphenation strategies for capillary electrophoresis-electrospray-mass spectrometry the technique has reemerged as technique with high separation power combined with high sensitivity in the analysis of peptides and protein digests. This review will discuss the newly developed hyphenation strategies for CE-ESI-MS and their application in bottom-up proteomics as well as the applications in the same time span, 2009 to present, using co-axial sheathliquid. Subsequently all separate aspects in the development of a CE-ESI-MS method for bottom-up proteomics shall be discussed, highlighting certain applications and discussing pros and cons of the various choices. The separation of peptides in a capillary electrophoresis system is discussed including the great potential for modeling of this migration of peptides due to the simple electrophoretic separation process. Furthermore, the technical aspects of method development are discussed, namely; background electrolyte choice, coating of the separation capillary and chosen loading method. Finally, conclusions and an outlook on future developments in the field of bottom-up proteomics by CE-ESI-MS will be provided.
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Affiliation(s)
- Anthonius A M Heemskerk
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2300, RC, Leiden, The Netherlands
| | - André M Deelder
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2300, RC, Leiden, The Netherlands
| | - Oleg A Mayboroda
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2300, RC, Leiden, The Netherlands
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15
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Self-assembled and covalently linked capillary coating of diazoresin and cyclodextrin-derived dendrimer for analysis of proteins by capillary electrophoresis. Talanta 2016; 152:76-81. [PMID: 26992496 DOI: 10.1016/j.talanta.2016.01.043] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 01/19/2016] [Accepted: 01/23/2016] [Indexed: 01/20/2023]
Abstract
Self-assembled and covalently linked capillary coatings of cyclodextrin-derived (CD) dendrimer were prepared using photosensitive diazoresin (DR) as a coupling agent. Layer by layer (LBL) self-assembled DR/CD-dendrimer coatings based on ionic bonding was fabricated first on the inner surface of capillary, and subsequently converted into covalent bonding after treatment with UV light through a unique photochemistry reaction of DR. Protein adsorption on the inner surface of capillary was suppressed by the DR/CD-dendrimer coating, and thus a baseline separation of lysozyme (Lys), myoglobin (Mb), bovine serum albumin (BSA) and ribonuclease A (RNase A) was achieved using capillary electrophoresis (CE). Compared with the bare capillary, the DR/CD-dendrimer covalently linked capillary coatings showed excellent protein separation performance with good stability and repeatability. Because of the replacement of highly toxic and moisture sensitive silane coupling agent by DR in the covalent coating preparation, this method may provide an environmentally friendly and simple way to prepare the covalently coated capillaries for CE.
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16
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Domínguez-Vega E, Haselberg R, Somsen GW. Capillary Zone Electrophoresis-Mass Spectrometry of Intact Proteins. Methods Mol Biol 2016; 1466:25-41. [PMID: 27473479 DOI: 10.1007/978-1-4939-4014-1_3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Capillary electrophoresis (CE) coupled with mass spectrometry (MS) has proven to be a powerful analytical tool for the characterization of intact proteins. It combines the high separation efficiency, short analysis time, and versatility of CE with the mass selectivity and sensitivity offered by MS detection. This chapter focuses on important practical considerations when applying CE-MS for the analysis of intact proteins. Technological aspects with respect to the use of CE-MS interfaces and application of noncovalent capillary coatings preventing protein adsorption are treated. Critical factors for successful protein analysis are discussed and four typical CE-MS systems are described demonstrating the characterization of different types of intact proteins by CE-MS. These methodologies comprise the use of sheath-liquid and sheathless CE-MS interfaces, and various types of noncovalent capillary coatings allowing efficient and reproducible protein separations. The discussion includes the analysis of lysozyme-drug conjugates and the therapeutic proteins human growth hormone, human interferon-β-1a, and human erythropoietin.
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Affiliation(s)
- Elena Domínguez-Vega
- Division of BioAnalytical Chemistry, VU University, de Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Rob Haselberg
- Division of BioAnalytical Chemistry, VU University, de Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Govert W Somsen
- Division of BioAnalytical Chemistry, VU University, de Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands.
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17
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Neuberger S, Rafai A, Neusüß C. Screening of Small Intact Proteins by Capillary Electrophoresis Electrospray Ionization-Mass Spectrometry (CE-ESI-MS). Methods Mol Biol 2016; 1466:43-56. [PMID: 27473480 DOI: 10.1007/978-1-4939-4014-1_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Capillary electrophoresis (CE) has been shown to be a suitable separation technique for complex samples. Combined with electrospray ionization-mass spectrometry (ESI-MS), it is a powerful tool offering the opportunity of high selectivity and sensitivity combined with the possibility to identify and characterize intact proteins. In this protocol, we demonstrate a screening method for intact proteins based on capillary zone electrophoresis (CZE) separation coupled with online mass spectrometric detection. In order to avoid protein-wall interactions, a neutral coated capillary is used to create a universal method for proteins with both low and high electrophoretic mobilities. In addition, we show the successful validation and application of this screening method for a set of eight standard proteins and the glycoprotein erythropoietin.
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Affiliation(s)
- Sabine Neuberger
- Department of Chemistry, Aalen University, Beethovenstraβe 1, Aalen, D-73430, Germany
| | | | - Christian Neusüß
- Department of Chemistry, Aalen University, Beethovenstraβe 1, Aalen, D-73430, Germany.
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18
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Bush DR, Zang L, Belov AM, Ivanov AR, Karger BL. High Resolution CZE-MS Quantitative Characterization of Intact Biopharmaceutical Proteins: Proteoforms of Interferon-β1. Anal Chem 2015; 88:1138-46. [DOI: 10.1021/acs.analchem.5b03218] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- David R. Bush
- Barnett
Institute, Northeastern University, 360 Huntington Ave, Boston, Massachusetts 02115, United States
| | - Li Zang
- Analytical
Development Department, Biogen, Cambridge, Massachusetts 02142, United States
| | - Arseniy M. Belov
- Barnett
Institute, Northeastern University, 360 Huntington Ave, Boston, Massachusetts 02115, United States
| | - Alexander R. Ivanov
- Barnett
Institute, Northeastern University, 360 Huntington Ave, Boston, Massachusetts 02115, United States
| | - Barry L. Karger
- Barnett
Institute, Northeastern University, 360 Huntington Ave, Boston, Massachusetts 02115, United States
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19
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Domínguez-Vega E, Haselberg R, Somsen GW, de Jong GJ. Simultaneous Assessment of Protein Heterogeneity and Affinity by Capillary Electrophoresis–Mass Spectrometry. Anal Chem 2015. [DOI: 10.1021/acs.analchem.5b01701] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- E. Domínguez-Vega
- Division
of BioAnalytical Chemistry, VU University Amsterdam, de Boelelaan
1083, 1081 HV Amsterdam, The Netherlands
| | - R. Haselberg
- Division
of BioAnalytical Chemistry, VU University Amsterdam, de Boelelaan
1083, 1081 HV Amsterdam, The Netherlands
| | - G. W. Somsen
- Division
of BioAnalytical Chemistry, VU University Amsterdam, de Boelelaan
1083, 1081 HV Amsterdam, The Netherlands
| | - G. J. de Jong
- Biomolecular
Analysis, Utrecht University, P.O. Box 80082, 3508 TB Utrecht, The Netherlands
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20
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Bekri S, Leclercq L, Cottet H. Polyelectrolyte multilayer coatings for the separation of proteins by capillary electrophoresis: Influence of polyelectrolyte nature and multilayer crosslinking. J Chromatogr A 2015; 1399:80-7. [DOI: 10.1016/j.chroma.2015.04.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 04/17/2015] [Accepted: 04/20/2015] [Indexed: 10/23/2022]
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21
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Acunha T, Ibáñez C, Pascual Reguera MI, Sarò M, Navarro R, Alfonso Redondo J, Reinecke H, Gallardo A, Simó C, Cifuentes A. Potential of prodendronic polyamines with modulated segmental charge density as novel coating for fast and efficient analysis of peptides and basic proteins by CE and CE-MS. Electrophoresis 2015; 36:1564-71. [DOI: 10.1002/elps.201400576] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 03/12/2015] [Accepted: 03/12/2015] [Indexed: 01/13/2023]
Affiliation(s)
- Tanize Acunha
- Laboratory of Foodomics; Institute of Food Science Research (CIAL); CSIC; Campus de Cantoblanco Madrid Spain
- CAPES Foundation; Ministry of Education of Brazil; Brasília DF Brazil
| | - Clara Ibáñez
- Laboratory of Foodomics; Institute of Food Science Research (CIAL); CSIC; Campus de Cantoblanco Madrid Spain
| | | | - Mariagiovanna Sarò
- Dipartimento di Scienze del Farmaco e dei Prodotti per la Salute, Facoltà di Farmacia; Università degli Studi di Messina; Messina Italy
| | - Rodrigo Navarro
- Instituto de Ciencia y Tecnología de Polímeros; ICTP-CSIC; Madrid
| | | | - Helmut Reinecke
- Instituto de Ciencia y Tecnología de Polímeros; ICTP-CSIC; Madrid
| | - Alberto Gallardo
- Instituto de Ciencia y Tecnología de Polímeros; ICTP-CSIC; Madrid
| | - Carolina Simó
- Laboratory of Foodomics; Institute of Food Science Research (CIAL); CSIC; Campus de Cantoblanco Madrid Spain
| | - Alejandro Cifuentes
- Laboratory of Foodomics; Institute of Food Science Research (CIAL); CSIC; Campus de Cantoblanco Madrid Spain
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22
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Pontillo C, Filip S, Borràs DM, Mullen W, Vlahou A, Mischak H. CE-MS-based proteomics in biomarker discovery and clinical application. Proteomics Clin Appl 2015; 9:322-34. [DOI: 10.1002/prca.201400115] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 11/10/2014] [Accepted: 01/14/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Claudia Pontillo
- Department of R&D; Mosaiques Diagnostics GmbH; Hanover Germany
- Charité-Universitätsmedizin Berlin; Berlin Germany
| | - Szymon Filip
- Charité-Universitätsmedizin Berlin; Berlin Germany
- Biotechnology Division; Biomedical Research Foundation; Academy of Athens; Athens Greece
| | - Daniel M. Borràs
- Department of R&D; ServiceXS; Leiden The Netherlands
- Institut National de la Santé et de la Recherche Médicale (INSERM); Institute of Cardiovascular and Metabolic Disease; Toulouse France
- Université Toulouse III Paul-Sabatier; Toulouse France
| | - William Mullen
- Institute of Cardiovascular and Medical Sciences; University of Glasgow; Glasgow UK
| | - Antonia Vlahou
- Biotechnology Division; Biomedical Research Foundation; Academy of Athens; Athens Greece
- School of Biomedical and Healthcare Sciences; Plymouth University; Plymouth UK
| | - Harald Mischak
- Department of R&D; Mosaiques Diagnostics GmbH; Hanover Germany
- Institute of Cardiovascular and Medical Sciences; University of Glasgow; Glasgow UK
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23
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Tamizi E, Jouyban A. The potential of the capillary electrophoresis techniques for quality control of biopharmaceuticals-A review. Electrophoresis 2015; 36:831-58. [DOI: 10.1002/elps.201400343] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 11/27/2014] [Accepted: 11/27/2014] [Indexed: 12/24/2022]
Affiliation(s)
- Elnaz Tamizi
- Biotechnology Research Center; Tabriz University of Medical Sciences; Tabriz Iran
| | - Abolghasem Jouyban
- Pharmacy Faculty and Drug Applied Research Center; Tabriz University of Medical Sciences; Tabriz Iran
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24
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Han X, Wang Y, Aslanian A, Fonslow B, Graczyk B, Davis TN, Yates JR. In-line separation by capillary electrophoresis prior to analysis by top-down mass spectrometry enables sensitive characterization of protein complexes. J Proteome Res 2014; 13:6078-86. [PMID: 25382489 PMCID: PMC4262260 DOI: 10.1021/pr500971h] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
![]()
Intact
protein analysis via top-down mass spectrometry (MS) provides
a bird’s eye view over the protein complexes and complex protein
mixtures with the unique capability of characterizing protein variants,
splice isoforms, and combinatorial post-translational modifications
(PTMs). Here we applied capillary electrophoresis (CE) through a sheathless
CE–electrospray ionization interface coupled to an LTQ Velos
Orbitrap Elite mass spectrometer to analyze the Dam1 complex from Saccharomyces cerevisiae. We achieved a 100-fold
increase in sensitivity compared to a reversed-phase liquid chromatography
coupled MS analysis of recombinant Dam1 complex with a total loading
of 2.5 ng (12 amol). N-terminal processing forms of individual subunits
of the Dam1 complex were observed as well as their phosphorylation
stoichiometry upon Mps1p kinase treatment.
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Affiliation(s)
- Xuemei Han
- Department of Chemical Physiology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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25
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Han X, Wang Y, Aslanian A, Bern M, Lavallée-Adam M, Yates JR. Sheathless capillary electrophoresis-tandem mass spectrometry for top-down characterization of Pyrococcus furiosus proteins on a proteome scale. Anal Chem 2014; 86:11006-12. [PMID: 25346219 PMCID: PMC4238646 DOI: 10.1021/ac503439n] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
![]()
Intact protein analysis via top-down
mass spectrometry (MS) provides
the unique capability of fully characterizing protein isoforms and
combinatorial post-translational modifications (PTMs) compared to
the bottom-up MS approach. Front-end protein separation poses a challenge
for analyzing complex mixtures of intact proteins on a proteomic scale.
Here we applied capillary electrophoresis (CE) through a sheathless
capillary electrophoresis-electrospray ionization (CESI) interface
coupled to an Orbitrap Elite mass spectrometer to profile the proteome
from Pyrococcus furiosus. CESI-top-down MS analysis
of Pyrococcus furiosus cell lysate identified 134
proteins and 291 proteoforms with a total sample consumption of 270
ng in 120 min of total analysis time. Truncations and various PTMs
were detected, including acetylation, disulfide bonds, oxidation,
glycosylation, and hypusine. This is the largest scale analysis of
intact proteins by CE-top-down MS to date.
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Affiliation(s)
- Xuemei Han
- Department of Chemical Physiology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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26
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New insights in carbohydrate-deficient transferrin analysis with capillary electrophoresis–mass spectrometry. Forensic Sci Int 2014; 243:14-22. [DOI: 10.1016/j.forsciint.2014.03.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 01/21/2014] [Accepted: 03/12/2014] [Indexed: 11/21/2022]
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27
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Vitali L, Della Betta F, Costa ACO, Vaz FAS, Oliveira MAL, Pereira Vistuba J, Fávere VT, Micke GA. New multilayer coating using quaternary ammonium chitosan and κ-carrageenan in capillary electrophoresis: Application in fast analysis of betaine and methionine. Talanta 2014; 123:45-53. [DOI: 10.1016/j.talanta.2014.01.047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/17/2014] [Accepted: 01/20/2014] [Indexed: 10/25/2022]
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28
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Batz NG, Mellors JS, Alarie JP, Ramsey JM. Chemical vapor deposition of aminopropyl silanes in microfluidic channels for highly efficient microchip capillary electrophoresis-electrospray ionization-mass spectrometry. Anal Chem 2014; 86:3493-500. [PMID: 24655020 DOI: 10.1021/ac404106u] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We describe a chemical vapor deposition (CVD) method for the surface modification of glass microfluidic devices designed to perform electrophoretic separations of cationic species. The microfluidic channel surfaces were modified using aminopropyl silane reagents. Coating homogeneity was inferred by precise measurement of the separation efficiency and electroosmotic mobility for multiple microfluidic devices. Devices coated with (3-aminopropyl)di-isopropylethoxysilane (APDIPES) yielded near diffusion-limited separations and exhibited little change in electroosmotic mobility between pH 2.8 and pH 7.5. We further evaluated the temporal stability of both APDIPES and (3-aminopropyl)triethoxysilane (APTES) coatings when stored for a total of 1 week under vacuum at 4 °C or filled with pH 2.8 background electrolyte at room temperature. Measurements of electroosmotic flow (EOF) and separation efficiency during this time confirmed that both coatings were stable under both conditions. Microfluidic devices with a 23 cm long, serpentine electrophoretic separation channel and integrated nanoelectrospray ionization emitter were CVD coated with APDIPES and used for capillary electrophoresis (CE)-electrospray ionization (ESI)-mass spectrometry (MS) of peptides and proteins. Peptide separations were fast and highly efficient, yielding theoretical plate counts over 600,000 and a peak capacity of 64 in less than 90 s. Intact protein separations using these devices yielded Gaussian peak profiles with separation efficiencies between 100,000 and 400,000 theoretical plates.
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Affiliation(s)
- Nicholas G Batz
- Department of Chemistry, ‡Department of Biomedical Engineering, and §Carolina Center for Genome Sciences, University of North Carolina , Chapel Hill, North Carolina 27599, United States
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29
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Targeting hepatocyte growth factor receptor (Met) positive tumor cells using internalizing nanobody-decorated albumin nanoparticles. Biomaterials 2014; 35:601-10. [DOI: 10.1016/j.biomaterials.2013.10.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 10/01/2013] [Indexed: 01/22/2023]
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30
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Clinical applications of capillary electrophoresis coupled to mass spectrometry in biomarker discovery: Focus on bladder cancer. Proteomics Clin Appl 2013; 7:779-93. [DOI: 10.1002/prca.201300038] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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31
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Stalmach A, Albalat A, Mullen W, Mischak H. Recent advances in capillary electrophoresis coupled to mass spectrometry for clinical proteomic applications. Electrophoresis 2013; 34:1452-64. [DOI: 10.1002/elps.201200708] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/07/2013] [Accepted: 02/14/2013] [Indexed: 12/14/2022]
Affiliation(s)
- Angelique Stalmach
- Department of Proteomics and Systems Medicine; BHF Glasgow Cardiovascular Research Centre; Institute of Cardiovascular and Medical Sciences; College of Medical Veterinary and Life Sciences; University of Glasgow; Glasgow; UK
| | - Amaya Albalat
- Department of Proteomics and Systems Medicine; BHF Glasgow Cardiovascular Research Centre; Institute of Cardiovascular and Medical Sciences; College of Medical Veterinary and Life Sciences; University of Glasgow; Glasgow; UK
| | - William Mullen
- Department of Proteomics and Systems Medicine; BHF Glasgow Cardiovascular Research Centre; Institute of Cardiovascular and Medical Sciences; College of Medical Veterinary and Life Sciences; University of Glasgow; Glasgow; UK
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32
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Haselberg R, Flesch FM, Boerke A, Somsen GW. Thickness and morphology of polyelectrolyte coatings on silica surfaces before and after protein exposure studied by atomic force microscopy. Anal Chim Acta 2013; 779:90-5. [DOI: 10.1016/j.aca.2013.03.066] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 03/25/2013] [Accepted: 03/27/2013] [Indexed: 10/26/2022]
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33
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Liu JX, Zhao MZ, Deng Y, Tie C, Chen HX, Zhou YL, Zhang XX. The coating of smart pH-responsive polyelectrolyte brushes in capillary and its application in CE. Electrophoresis 2013; 34:1352-8. [PMID: 23436557 DOI: 10.1002/elps.201200518] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 01/02/2013] [Accepted: 01/10/2013] [Indexed: 11/07/2022]
Abstract
A novel pH-responsive coating technique was developed and applied to CE successfully in this paper. The coating was formed by bonding mixed opposite charge poly(acrylic acid) and poly(2-vinylpyridine) randomly onto the inner wall of a silica capillary. The coating processes were first characterized by ellipsometry and atomic force microscopy at macroscale and microscale, respectively. Measurements of EOF were implemented to confirm the coating. Direction and velocity of EOF became controllable from negative to positive, showing a perfect sigmoidal curve as the coating net charges alternated by the pH of BGE. The control of the EOF makes it possible to analyze different kinds of small molecules, peptides, and proteins successfully in the same capillary. Results showed that the stability and reproducibility for separations of fluoroquinolone standards were satisfactory for more than a hundred separations. A series of basic and acidic protein standards were separated with admirable efficiency and minimal adsorption using both polarities. The separation of tryptic BSA digest showed that the prepared capillary has immense potential in analyzing a single sample with both acidic and basic separations, which achieved the expectation in proteomics study by CE-MS.
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Affiliation(s)
- Jing-Xin Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry, Peking University, Beijing, PR China
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34
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Haselberg R, de Jong GJ, Somsen GW. Low-Flow Sheathless Capillary Electrophoresis–Mass Spectrometry for Sensitive Glycoform Profiling of Intact Pharmaceutical Proteins. Anal Chem 2013; 85:2289-96. [DOI: 10.1021/ac303158f] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Rob Haselberg
- Biomolecular Analysis, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Gerhardus J. de Jong
- Biomolecular Analysis, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Govert W. Somsen
- Biomolecular Analysis, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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35
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Yu B, Cui W, Cong H, Jiao M, Liu P, Yang S. A novel diazoresin/polyethylene glycol covalent capillary coating for analysis of proteins by capillary electrophoresis. RSC Adv 2013. [DOI: 10.1039/c3ra23328f] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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36
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Haselberg R, de Jong GJ, Somsen GW. CE-MS for the analysis of intact proteins 2010-2012. Electrophoresis 2012; 34:99-112. [DOI: 10.1002/elps.201200439] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 10/08/2012] [Accepted: 10/09/2012] [Indexed: 12/18/2022]
Affiliation(s)
- Rob Haselberg
- Biomolecular Analysis; Utrecht University; CG Utrecht; The Netherlands
| | | | - Govert W. Somsen
- Biomolecular Analysis; Utrecht University; CG Utrecht; The Netherlands
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37
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Bonvin G, Schappler J, Rudaz S. Capillary electrophoresis–electrospray ionization-mass spectrometry interfaces: Fundamental concepts and technical developments. J Chromatogr A 2012; 1267:17-31. [DOI: 10.1016/j.chroma.2012.07.019] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 07/04/2012] [Accepted: 07/06/2012] [Indexed: 01/24/2023]
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Wang C, Lee CS, Smith RD, Tang K. Ultrasensitive sample quantitation via selected reaction monitoring using CITP/CZE-ESI-triple quadrupole MS. Anal Chem 2012; 84:10395-403. [PMID: 23140208 DOI: 10.1021/ac302616m] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We demonstrate the direct coupling of transient capillary isotachophoresis/capillary zone electrophoresis (CITP/CZE) with a high-sensitivity triple quadrupole mass spectrometer operating in selected reaction monitoring (SRM) mode for sample quantitation. The capability of CITP/CZE for in situ sample enrichment and separation has been shown to significantly improve the analytical figures of merit. A linear dynamic range spanning 4 orders of magnitude was observed. An average signal-to-noise ratio (S/N) of 49.6 was observed for 50 amol of targeted peptide in the presence of a complex and much more abundant bovine serum albumin (BSA) digest. Correlation of variation (CV) of <10% for peak area was measured from triplicate sample analyses at 50 pM peptide concentration, showing good reproducibility of this online CITP/CZE-SRM mass spectrometry (MS) platform, and with limit of quantitation (LOQ) demonstrated to be well below 50 pM.
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Affiliation(s)
- Chenchen Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, 20742, United States
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Pioch M, Bunz SC, Neusüss C. Capillary electrophoresis/mass spectrometry relevant to pharmaceutical and biotechnological applications. Electrophoresis 2012; 33:1517-30. [PMID: 22736352 DOI: 10.1002/elps.201200030] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Advanced analytical techniques play a crucial role in the pharmaceutical and biotechnological field. In this context, capillary electrophoresis/mass spectrometry (CE/MS) has attracted attention due to efficient and selective separation in combination with powerful detection allowing identification and detailed characterization. Method developments and applications of CE/MS have been focused on questions not easily accessible by liquid chromatography/mass spectrometry (LC/MS) as the analysis of intact proteins, carbohydrates, and various small molecules, including peptides. Here, recent approaches and applications of CE/MS relevant to (bio)pharmaceuticals are reviewed and discussed to show actual developments and future prospects. Based on other reviews on related subjects covering large parts of previous works, the paper is focused on general ideas and contributions of the last 2 years; for the analysis of glycans, the period is extended back to 2006.
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Affiliation(s)
- Markus Pioch
- Chemistry Department, Aalen University, Aalen, Germany
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Zhao SS, Zhong X, Tie C, Chen DD. Capillary electrophoresis-mass spectrometry for analysis of complex samples. Proteomics 2012; 12:2991-3012. [DOI: 10.1002/pmic.201200221] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/10/2012] [Accepted: 07/18/2012] [Indexed: 12/20/2022]
Affiliation(s)
- Shuai Sherry Zhao
- Department of Chemistry; University of British Columbia; Vancouver BC Canada
| | - Xuefei Zhong
- Department of Chemistry; University of British Columbia; Vancouver BC Canada
| | - Cai Tie
- Department of Chemistry; University of British Columbia; Vancouver BC Canada
| | - David D.Y. Chen
- Department of Chemistry; University of British Columbia; Vancouver BC Canada
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Yu B, Liu P, Cong H, Tang J, Zhang L. Novel covalently coated diazoresin/polyvinyl alcohol capillary column for the analysis of proteins by capillary electrophoresis. Electrophoresis 2012; 33:3066-72. [PMID: 22996666 DOI: 10.1002/elps.201200245] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 07/16/2012] [Accepted: 07/17/2012] [Indexed: 12/28/2022]
Abstract
A novel method for the preparation of covalently linked capillary coatings of PVA was demonstrated using photosensitive diazoresin (DR) as coupling agents. Layer-by-layer self-assembly film of DR and PVA based on hydrogen bonding was first fabricated on the inner wall of capillary, then the hydrogen bonding was converted into covalent bonding after treatment with UV light through the unique photochemistry reaction of DR. The covalently bonded coatings suppressed basic protein adsorption on the inner surface of capillary, and thus a baseline separation of lysozyme, cytochrome c and BSA was achieved using CE. Compared with bare capillary or noncovalently bonded DR/PVA coatings, the covalently linked DR/PVA capillary coatings not only improved the CE separation performance for proteins, but also exhibited good stability and repeatability. Due to the replacement of highly toxic and moisture-sensitive silane coupling agent by DR in the covalent coating preparation, this method may provide a green and easy way to make the covalently coated capillaries for CE.
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Affiliation(s)
- Bing Yu
- College of Chemical and Environmental Engineering, Qingdao University, Qingdao, P. R. China.
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42
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Kašička V. Recent developments in CE and CEC of peptides (2009-2011). Electrophoresis 2011; 33:48-73. [DOI: 10.1002/elps.201100419] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Revised: 09/19/2011] [Accepted: 09/20/2011] [Indexed: 12/12/2022]
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Haselberg R, Harmsen S, Dolman MEM, de Jong GJ, Kok RJ, Somsen GW. Characterization of drug-lysozyme conjugates by sheathless capillary electrophoresis-time-of-flight mass spectrometry. Anal Chim Acta 2011; 698:77-83. [PMID: 21645662 DOI: 10.1016/j.aca.2011.04.050] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 04/22/2011] [Accepted: 04/25/2011] [Indexed: 12/27/2022]
Abstract
Drug-protein conjugates have been widely used for the cell-specific targeting of drugs to cells that can bind and internalize the proteinaceous carrier. For renal drug targeting, lysozyme (LZM) can be used as an effective carrier that accumulates in proximal tubular cells. We used capillary electrophoresis-time-of-flight mass spectrometry (CE-TOF-MS) for the characterization of different drug-LZM conjugates. A recently developed prototype porous tip sprayer was employed for sheathless electrospray ionization (ESI) CE-MS interfacing. In order to prevent adsorption of LZM conjugates to the capillary wall, a positively charged polyethylenimine capillary coating was used in combination with a low-pH background electrolyte. Drug-LZM products had been prepared by first coupling BOC-l-methionine hydroxysuccinimide ester (BOCmet) to lysine residues of LZM followed by conjugation with the kinase inhibitors LY364947, erlotinib, or Y27632 via a platinum(II)-based linker. CE-TOF-MS of each preparation showed narrow symmetrical peaks for the various reaction products demonstrating that drug-LZM conjugates remained stable during the CE analysis and subsequent ESI. Components observed in the drug-LZM products were assigned based on their relative migration times and on molecular mass as obtained by TOF-MS. The TOF-MS data obtained for the individual components revealed that the preparations contained LZM carrying one or two drug molecules, next to unmodified and BOCmet-modified LZM. Based on relative peak areas (assuming an equimolar response for each component) a quantitative conjugate profile could be derived for every preparation leading to drug loading values of 0.4-0.6 mol drug per mole protein.
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Affiliation(s)
- R Haselberg
- Biomolecular Analysis, Utrecht Institute of Pharmaceutical Sciences, Utrecht University, The Netherlands.
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Haselberg R, Brinks V, Hawe A, de Jong GJ, Somsen GW. Capillary electrophoresis-mass spectrometry using noncovalently coated capillaries for the analysis of biopharmaceuticals. Anal Bioanal Chem 2011; 400:295-303. [PMID: 21318246 PMCID: PMC3062027 DOI: 10.1007/s00216-011-4738-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 12/24/2010] [Accepted: 01/27/2011] [Indexed: 10/29/2022]
Abstract
In this work, the usefulness of capillary electrophoresis-electrospray ionization time-of-flight-mass spectrometry for the analysis of biopharmaceuticals was studied. Noncovalently bound capillary coatings consisting of Polybrene-poly(vinyl sulfonic acid) or Polybrene-dextran sulfate-Polybrene were used to minimize protein and peptide adsorption, and achieve good separation efficiencies. The potential of the capillary electrophoresis-mass spectrometry (CE-MS) system to characterize degradation products was investigated by analyzing samples of the drugs, recombinant human growth hormone (rhGH) and oxytocin, which had been subjected to prolonged storage, heat exposure, and/or different pH values. Modifications could be assigned based on accurate masses as obtained with time-of-flight-mass spectrometry (TOF-MS) and migration times with respect to the parent compound. For heat-exposed rhGH, oxidations, sulfonate formation, and deamidations were observed. Oxytocin showed strong deamidation (up to 40%) upon heat exposure at low pH, whereas at medium and high pH, mainly dimer (>10%) and trisulfide formation (6-7%) occurred. Recombinant human interferon-β-1a (rhIFN-β) was used to evaluate the capability of the CE-MS method to assess glycan heterogeneity of pharmaceutical proteins. Analysis of this N-glycosylated protein revealed a cluster of resolved peaks which appeared to be caused by at least ten glycoforms differing merely in sialic acid and hexose N-acetylhexosamine composition. Based on the relative peak area (assuming an equimolar response per glycoform), a quantitative profile could be derived with the disialytated biantennary glycoform as most abundant (52%). Such a profile may be useful for in-process and quality control of rhIFN-β batches. It is concluded that the separation power provided by combined capillary electrophoresis and TOF-MS allows discrimination of highly related protein species.
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Affiliation(s)
- R Haselberg
- Department of Biomedical Analysis, Utrecht University, PO Box 80082, 3508 TB Utrecht, The Netherlands.
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Haselberg R, de Jong GJ, Somsen GW. Capillary electrophoresis-mass spectrometry for the analysis of intact proteins 2007-2010. Electrophoresis 2010; 32:66-82. [PMID: 21171114 DOI: 10.1002/elps.201000364] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 09/07/2010] [Accepted: 09/08/2010] [Indexed: 12/29/2022]
Abstract
CE coupled to MS has proven to be a powerful analytical tool for the characterization of intact proteins, as it combines the high separation efficiency of CE with the selectivity of MS. This review provides an overview of the development and application of CE-MS methods within the field of intact protein analysis as published between January 2007 and June 2010. Ongoing technological developments with respect to CE-MS interfacing, capillary coatings for CE-MS, coupling of CIEF with MS and chip-based CE-MS are treated. Furthermore, CE-MS of intact proteins involving ESI, MALDI and ICP ionization is outlined and overviews of the use of the various CE-MS methods are provided by tables. Representative examples illustrate the applicability of CE-MS for the characterization of proteins, including glycoproteins, biopharmaceuticals, protein-ligand complexes, biomarkers and dietary proteins. It is concluded that CE-MS is a valuable technique with high potential for intact protein analysis, providing useful information on protein identity and purity, including modifications and degradation products.
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Affiliation(s)
- Rob Haselberg
- Department of Biomedical Analysis, Utrecht University, TB Utrecht, The Netherlands.
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Haselberg R, Ratnayake CK, de Jong GJ, Somsen GW. Performance of a sheathless porous tip sprayer for capillary electrophoresis–electrospray ionization-mass spectrometry of intact proteins. J Chromatogr A 2010; 1217:7605-11. [DOI: 10.1016/j.chroma.2010.10.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 08/26/2010] [Accepted: 10/04/2010] [Indexed: 11/29/2022]
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