1
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Chen CJ, Chang CT, Lin ZR, Chiu WC, Liu JY, Ye ZC, Wang CJ, Shieh YT, Liu MY. Coupling capillary electrophoresis with mass spectrometry for the analysis of oxidized phospholipids in human high-density lipoproteins. Electrophoresis 2024; 45:333-345. [PMID: 37985935 DOI: 10.1002/elps.202300139] [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: 06/27/2023] [Revised: 10/12/2023] [Accepted: 10/13/2023] [Indexed: 11/22/2023]
Abstract
The oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (ox-PAPC) products in human high-density lipoproteins (HDLs) were investigated by low-flow capillary electrophoresis-mass spectrometry (low-flow CE-MS). To accelerate the optimization, native PAPC (n-PAPC) standard was first analyzed by a commercial CE instrument with a photodiode array detector. The optimal separation buffer contained 60% (v/v) acetonitrile, 40% (v/v) methanol, 20 mM ammonium acetate, 0.5% (v/v) formic acid, and 0.1% (v/v) water. The selected separation voltage and capillary temperature were 20 kV and 23°C. The optimal CE separation buffer was then used for the low-flow CE-MS analysis. The selected MS conditions contained heated capillary temperature (250°C), capillary voltage (10 V), and injection time (1 s). No sheath gas was used for MS. The linear range for n-PAPC was 2.5-100.0 µg/mL. The coefficient of determination (R2 ) was 0.9918. The concentration limit of detection was 1.52 µg/mL, and the concentration limit of quantitation was 4.60 µg/mL. The optimal low-flow CE-MS method showed good repeatability and sensitivity. The ox-PAPC products in human HDLs were determined based on the in vitro ox-PAPC products of n-PAPC standard. Twenty-one ox-PAPC products have been analyzed in human HDLs. Uremic patients showed significantly higher levels of 15 ox-PAPC products than healthy subjects.
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Affiliation(s)
- Chao-Jung Chen
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
- Department of Medical Research, Proteomics Core Laboratory, China Medical University Hospital, Taichung, Taiwan
| | - Chiz-Tzung Chang
- Department of Medicine, China Medical University Hospital, Taichung, Taiwan
- College of Medicine, China Medical University, Taichung, Taiwan
| | - Zhi-Ru Lin
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Wen-Chien Chiu
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Jia-Yuan Liu
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Zhi-Cheng Ye
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Chuan-Jun Wang
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Ying-Tzu Shieh
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Mine-Yine Liu
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
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2
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Bagwe K, Gould N, Johnson KR, Ivanov AR. Single-cell omic molecular profiling using capillary electrophoresis-mass spectrometry. Trends Analyt Chem 2023; 165:117117. [PMID: 37388554 PMCID: PMC10306258 DOI: 10.1016/j.trac.2023.117117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
Tissues and other cell populations are highly heterogeneous at the cellular level, owing to differences in expression and modifications of proteins, polynucleotides, metabolites, and lipids. The ability to assess this heterogeneity is crucial in understanding numerous biological phenomena, including various pathologies. Traditional analyses apply bulk-cell sampling, which masks the potentially subtle differences between cells that can be important in understanding of biological processes. These limitations due to cell heterogeneity inspired significant efforts and interest toward the analysis of smaller sample sizes, down to the level of individual cells. Among the emerging techniques, the unique capabilities of capillary electrophoresis coupled with mass spectrometry (CE-MS) made it a prominent technique for proteomics and metabolomics analysis at the single-cell level. In this review, we focus on the application of CE-MS in the proteomic and metabolomic profiling of single cells and highlight the recent advances in sample preparation, separation, MS acquisition, and data analysis.
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Affiliation(s)
- Ketki Bagwe
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
| | - Noah Gould
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
| | - Kendall R. Johnson
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
| | - Alexander R. Ivanov
- Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States
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3
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Mostafa ME, Hayes MM, Grinias JP, Bythell BJ, Edwards JL. Supercritical Fluid Nanospray Mass Spectrometry: II. Effects on Ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023. [PMID: 37097105 DOI: 10.1021/jasms.2c00372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Nanospraying supercritical fluids coupled to a mass spectrometer (nSF-MS) using a 90% supercritical fluid CO2 carrier (sCO2) has shown an enhanced desolvation compared to traditional liquid eluents. Capillaries of 25, 50, and 75 μm internal diameter (i.d.) with pulled emitter tips provided high MS detection sensitivity. Presented here is an evaluation of the effect of proton affinity, hydrophobicity, and nanoemitter tip size on the nSF-MS signal. This was done using a set of primary, secondary, tertiary, and quaternary amines with butyl, hexyl, octyl, and decyl chains as analytes. Each amine class was analyzed individually to evaluate hydrophobicity and proton affinity effects on signal intensity. The system has shown a mass sensitive detection on a linear dynamic range of 0.1-100 μM. Results indicate that hydrophobicity has a larger effect on the signal response than proton affinity. Nanospraying a mixture of all amine classes using the 75 μm emitter has shown a quaternary amine signal not suppressed by competing analytes. Competing ionization was observed for primary, secondary, and tertiary amines. The 75 and 50 μm emitters demonstrated increased signal with increasing hydrophobicity. Surprisingly, the 25 μm i.d. emitter yielded a signal decrease as the alkyl chain length increased, contrary to conventional understanding. Nanospraying the evaporative fluid in a sub-500 nm emitter likely resulted in differences in the ionization mechanism. Results suggest that 90% sCO2 with 9.99% methanol and 0.01% formic acid yielded fast desolvation, high ionization efficiency, and low matrix effect, which could benefit complex biological matrix analysis.
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Affiliation(s)
- Mahmoud Elhusseiny Mostafa
- Department of Chemistry and Biochemistry, Saint Louis University, 3501 Laclede Ave., St. Louis, Missouri 63103, United States
| | - Madisyn M Hayes
- Department of Chemistry and Biochemistry, Ohio University, 307 Chemistry Building, Athens, Ohio 45701, United States
| | - James P Grinias
- Department of Chemistry and Biochemistry, Rowan University, 201 Mullica Hill Rd., Glassboro, New Jersey 08028, United States
| | - Benjamin J Bythell
- Department of Chemistry and Biochemistry, Ohio University, 307 Chemistry Building, Athens, Ohio 45701, United States
| | - James L Edwards
- Department of Chemistry and Biochemistry, Saint Louis University, 3501 Laclede Ave., St. Louis, Missouri 63103, United States
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4
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Chang CT, Chiu WC, Lin ZR, Shieh YT, Chang IT, Hsia MH, Wang CJ, Chen CJ, Liu MY. Determination of oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine products in human very low-density lipoproteins by nonaqueous low-flow capillary electrophoresis-mass spectrometry. J Chromatogr A 2023; 1687:463694. [PMID: 36502642 DOI: 10.1016/j.chroma.2022.463694] [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: 09/16/2022] [Revised: 11/29/2022] [Accepted: 11/29/2022] [Indexed: 12/03/2022]
Abstract
A simple and fast low-flow capillary electrophoresis-mass spectrometry (low-flow CE-MS) method has been developed to analyze oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (ox-PAPC) products in human very low-density lipoproteins (VLDLs). Native PAPC standard was analyzed to optimize the low-flow CE-MS method. The optimal CE conditions included separation buffer (60% (v/v) acetonitrile, 40% (v/v) methanol, 0.1% (v/v) water, 0.5% (v/v) formic acid, 20 mM ammonium acetate), sheath liquid (60% (v/v) acetonitrile, 40% (v/v) methanol, 0.1% (v/v) water, 20 mM ammonium acetate), separation voltage (20 kV), separation capillary internal diameter (i.d.) (75 µm), separation capillary temperature (23˚C) and sample injection time (6 s). The selected MS conditions included heated capillary temperature (250°C), capillary voltage (10 V), and injection time (1 s). Sheath gas was not used in this study. The total ion chromatograms (TICs), extracted ion chromatograms (EICs) and MS spectra of native PAPC standard and its in vitro oxidation products showed good repeatability and sensitivity. To determine the ox-PAPC products in human VLDLs, the EICs and MS spectra of VLDLs were compared with the in vitro oxidation products of native PAPC standard. For native PAPC standard, the measured linear range was 2.5 - 100.0 µg/mL, and the coefficients of determination (R2) was 0.9994. The concentration limit of detection (LOD) was 0.44 µg/mL, and the concentration limit of quantitation (LOQ) was 1.34 µg/mL. A total of 21 ox-PAPC products were analyzed for the VLDLs of healthy and uremic subjects. The levels of 7 short-chain and 5 long-chain ox-PAPC products on uremic VLDLs were significantly higher than healthy VLDLs. This simple low-flow CE-MS method might be a good alternative for LC-MS for the analysis of ox-PAPC products. Furthermore, it might also help scientists to expedite the search for uremic biomarkers.
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Affiliation(s)
- Chiz-Tzung Chang
- Department of Medicine, China Medical University Hospital, Taichung, Taiwan; College of Medicine, China Medical University, Taichung, Taiwan
| | - Wen-Chien Chiu
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Zhi-Ru Lin
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Ying-Tzu Shieh
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - I-Ting Chang
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Min-Hui Hsia
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Chuan-Jun Wang
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan
| | - Chao-Jung Chen
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan; Proteomics Core Laboratory, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.
| | - Mine-Yine Liu
- Department of Chemistry, National Changhua University of Education, Changhua, Taiwan.
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5
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Han M, Smith R, Rock DA. Capillary Electrophoresis-Mass Spectrometry (CE-MS) by Sheath-Flow Nanospray Interface and Its Use in Biopharmaceutical Applications. Methods Mol Biol 2022; 2531:15-47. [PMID: 35941476 DOI: 10.1007/978-1-0716-2493-7_2] [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
Both capillary electrophoresis (CE) and mass spectrometry (MS) technologies are powerful analytical tools that have been used extensively in the characterization of biologics in the biopharmaceutical industry. The direct coupling of CE with MS is an attractive approach, in that the high separation capability of CE and the ultrasensitive detection and accurate identification performance of MS can be combined to provide a powerful system for the analysis of complex analytes. In this chapter, we discuss the detailed procedure of carrying out CE-MS analysis using a nano sheath-flow interface and its applications including intact mass analysis of monoclonal antibodies and fusion proteins, and a biotransformation study of two Fc-FGF21 molecules in a single-dose pharmacokinetic mice study. Optimization processes, including the finetuning of CE conditions and MS parameters, are illustrated in this chapter, with focuses on method robustness and assay reproducibility.
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Affiliation(s)
- Mei Han
- Pharmacokinetics and Drug Metabolism, Amgen Research, Amgen Inc., South San Francisco, CA, USA.
| | - Richard Smith
- Pharmacokinetics and Drug Metabolism, Amgen Research, Amgen Inc., South San Francisco, CA, USA
| | - Dan A Rock
- Pharmacokinetics and Drug Metabolism, Amgen Research, Amgen Inc., South San Francisco, CA, USA
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6
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Kawai T, Matsumori N, Otsuka K. Recent advances in microscale separation techniques for lipidome analysis. Analyst 2021; 146:7418-7430. [PMID: 34787600 DOI: 10.1039/d1an00967b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review paper highlights the recent research on liquid-phase microscale separation techniques for lipidome analysis over the last 10 years, mainly focusing on capillary liquid chromatography (LC) and capillary electrophoresis (CE) coupled with mass spectrometry (MS). Lipids are one of the most important classes of biomolecules which are involved in the cell membrane, energy storage, signal transduction, and so on. Since lipids include a variety of hydrophobic compounds including numerous structural isomers, lipidomes are a challenging target in bioanalytical chemistry. MS is the key technology that comprehensively identifies lipids; however, separation techniques like LC and CE are necessary prior to MS detection in order to avoid ionization suppression and resolve structural isomers. Separation techniques using μm-scale columns, such as a fused silica capillary and microfluidic device, are effective at realizing high-resolution separation. Microscale separation usually employs a nL-scale flow, which is also compatible with nanoelectrospray ionization-MS that achieves high sensitivity. Owing to such analytical advantages, microscale separation techniques like capillary/microchip LC and CE have been employed for more than 100 lipidome studies. Such techniques are still being evolved and achieving further higher resolution and wider coverage of lipidomes. Therefore, microscale separation techniques are promising as the fundamental technology in next-generation lipidome analysis.
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Affiliation(s)
- Takayuki Kawai
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Nobuaki Matsumori
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Koji Otsuka
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
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7
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Helena H, Ivona V, Roman Ř, František F. Current applications of capillary electrophoresis-mass spectrometry for the analysis of biologically important analytes in urine (2017 to mid-2021): A review. J Sep Sci 2021; 45:305-324. [PMID: 34538010 PMCID: PMC9292318 DOI: 10.1002/jssc.202100621] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/07/2021] [Accepted: 09/10/2021] [Indexed: 12/17/2022]
Abstract
Capillary electrophoresis coupled online with mass detection is a modern tool for analyzing wide ranges of compounds in complex samples, including urine. Capillary electrophoresis with mass spectrometry allows the separation and identification of various analytes spanning from small ions to high molecular weight protein complexes. Similarly to the much more common liquid chromatography‐mass spectrometry techniques, the capillary electrophoresis separation reduces the complexity of the mixture of analytes entering the mass spectrometer resulting in reduced ion suppression and a more straightforward interpretation of the mass spectrometry data. This review summarizes capillary electrophoresis with mass spectrometry studies published between the years 2017 and 2021, aiming at the determination of various compounds excreted in urine. The properties of the urine, including its diagnostical and analytical features and chemical composition, are also discussed including general protocols for the urine sample preparation. The mechanism of the electrophoretic separation and the instrumentation for capillary electrophoresis with mass spectrometry coupling is also included. This review shows the potential of the capillary electrophoresis with mass spectrometry technique for the analyses of different kinds of analytes in a complex biological matrix. The discussed applications are divided into two main groups (capillary electrophoresis with mass spectrometry for the determination of drugs and drugs of abuse in urine and capillary electrophoresis with mass spectrometry for the studies of urinary metabolome).
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Affiliation(s)
- Hrušková Helena
- Institute of Analytical Chemistry, Czech Academy of Sciences, Brno, Czech Republic.,Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Voráčová Ivona
- Institute of Analytical Chemistry, Czech Academy of Sciences, Brno, Czech Republic
| | - Řemínek Roman
- Institute of Analytical Chemistry, Czech Academy of Sciences, Brno, Czech Republic
| | - Foret František
- Institute of Analytical Chemistry, Czech Academy of Sciences, Brno, Czech Republic
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8
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Affiliation(s)
- Takayuki KAWAI
- RIKEN Center for Biosystems Dynamics Research
- Graduate School of Frontier Biosciences, Osaka University
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9
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Xu X. Capillary Electrophoresis-Mass Spectrometry for Cancer Metabolomics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1280:189-200. [PMID: 33791983 DOI: 10.1007/978-3-030-51652-9_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
This chapter presents the fundamentals, instrumentation, methodology, and applications of capillary electrophoresis-mass spectrometry (CE-MS) for cancer metabolomics. CE offers fast and high-resolution separation of charged analytes from a very small amount of sample. When coupled to MS, it represents a powerful analytical technique enabling identification and quantification of metabolites in biological samples. Several issues need to be addressed when combining CE with MS, especially the interface between CE and MS and the selection of a proper separation methodology, sample pretreatment, and capillary coatings. We will discuss these aspects of CE-MS and detail representative applications for cancer metabolomic analysis.
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Affiliation(s)
- Xiangdong Xu
- School of Public Health and Key Laboratory of Environment and Human Health, Hebei Medical University, Shijiazhuang, China.
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10
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Vermeire PJ, Van Schepdael A, Petersen NJ. Development of a novel sheathless CE-ESI-MS interface via a CO 2 laser ablated opening. Talanta 2020; 214:120853. [PMID: 32278416 DOI: 10.1016/j.talanta.2020.120853] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 02/13/2020] [Accepted: 02/15/2020] [Indexed: 11/18/2022]
Abstract
A new and easy to construct sheathless capillary electrophoresis electro spray ionization mass spectrometry (CE-ESI-MS) interface was developed that offers several advantages compared to traditional liquid junction interfaces. The fabrication of the device only requires a CO2 laser engraver that most groups working with microfluids have access to. It only takes a few seconds to create a CO2 laser ablated opening in the bare-fused silica capillaries and the opening can be placed as close as a few mm from the spray tip. The capillary is punctured through a silicone tube such that the opening is directly placed inside this tube, which also serves as a liquid reservoir for the make-up liquid. Electrical contact required for both CE separation and ESI is established via the liquid in this reservoir which is in contact with the electrode of an external high voltage power supply. The developed CE-ESI-MS interface is capable of analysing both small molecules and biomolecules such as peptides in physisorbed PEG polymer brush coated capillaries. Proof-of-principle of the interface was demonstrated by analysing a tryptic digest of BSA. Further, a range of drugs of abuse were also investigated. The examined small molecules (pethidine, nortriptyline, methadone, haloperidol and loperamide) have a quantification limit (LOQ) of 150 ng/mL and a detection limit (LOD) of 40 ng/mL (except for loperamide: LOD = 80 ng/mL). Finally, we used our novel CE-MS interface for the analysis of the Aβ40 peptide. This is a member of the beta-Amyloid peptide family, involved in the development of Alzheimer's disease. A LOQ of 9 μg/mL was obtained for Aβ40, corresponding to 23 fmoles in a sample volume of 11 nL.
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Affiliation(s)
- Pieter-Jan Vermeire
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49, O&N2 PB 822, 3000, Leuven, Belgium.
| | - Ann Van Schepdael
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Herestraat 49, O&N2 PB 822, 3000, Leuven, Belgium
| | - Nickolaj J Petersen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark
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11
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Zhang H, Lou C, Li J, Kang J. A gold foil covered fused silica capillary tip as a sheathless interface for coupling capillary electrophoresis-mass spectrometry. J Chromatogr A 2020; 1624:461215. [PMID: 32540065 DOI: 10.1016/j.chroma.2020.461215] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/19/2022]
Abstract
A method for the preparation of an on-column ESI emitter used as the sheathless interface for coupling capillary electrophoresis (CE) with mass spectrometry (MS) was developed. The emitter was directly fabricated at the outlet end of the separation capillary which was etched with HF solution to a symmetrical tip. The tip was covered with a small piece of gold foil which was fixed by epoxy resin glue for electrical contact. Such a prepared ESI emitter can produce a stable ESI signal over the wide range of flow rate from 50 nL/min to 800 nL/min. The performance of the CE-MS with the sheathless interface was evaluated by using the separation of four alkaloids. It was found that the strong electroosmotic flow produced by the multiple polyelectrolyte coating on the capillary is necessary for maintaining a stable MS signal. Effect of the running buffer composition, concentration and the CE separation voltages on the ESI signal strength were investigated. The absolute detection limits for the alkaloids was determined as fmol level. Moreover, the CE-MS was applied for the analyses of trypsin digestion of cytochrome C and small molecular organic anions. The emitter performed very stable with a lifetime of at least 180 h.
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Affiliation(s)
- Hanzhi Zhang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China; Shanghai Institute for Food and Drug Control, Zhangheng Road 1500, Shanghai 201203, China
| | - Chunli Lou
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China; School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Shanghai 200120, China
| | - Jing Li
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China; School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Shanghai 200120, China
| | - Jingwu Kang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China; School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Shanghai 200120, China.
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12
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Tie C, Liu L, Feng T, Sa R, Xia Q, Liang H, Mao Y. Differential analysis of urinary albumin for membranous nephropathy patients by online capillary isoelectric focusing - Mass spectrometry. J Proteomics 2020; 216:103676. [PMID: 32006679 DOI: 10.1016/j.jprot.2020.103676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/10/2020] [Accepted: 01/28/2020] [Indexed: 12/27/2022]
Abstract
Membranous nephropathy (MN) is one of the most common causes of primary glomerular diseases worldwide. The M-type phospholipase A2 receptor (PLA2R), an antigen expressed in more than 70% of cases of idiopathic membranous nephropathy (IMN), is a biomarker which is now used by physicians for clinical diagnosis. Despite the prevalence of PLA2R in the cases of MN, it is not always effective to use PLA2R for differentiating primary or secondary MNs. On the other hand, urinary albumin assay is one of the de facto tests for kidney function testing for several decades. In this work, urinary albumin species between primary and secondary MN patients are compared using a newly developed capillary isoelectric focusing - mass spectrometry (CIEF-MS) technology. The distinct patterns of cationic and acidic urinary albumin species, as revealed by this novel CIEF-MS technology, suggest potential applications of this differential analysis for subtyping of membranous nephropathy. Further investigation of these cationic human albumin species in urine may provide clues to the disease onset and development of MN, thus facilitating treatment. In addition, this novel workflow of using CIEF-MS for urinary protein analysis may be beneficial to the research, pathology, prognosis, and diagnosis of many other types of kidney diseases, such as chronic kidney disease, diabetic nephrology, etc.
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Affiliation(s)
- Cai Tie
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology (Beijing), Beijing 100083, PR China; School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, PR China.
| | - Lili Liu
- Department of Nephrology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing 100730, PR China
| | - Teng Feng
- CMP Scientific Corp, 760 Parkside Avenue, STE 211, Brooklyn, New York 11226, United States
| | - Rina Sa
- CMP Scientific Corp, 760 Parkside Avenue, STE 211, Brooklyn, New York 11226, United States
| | - Qiangwei Xia
- CMP Scientific Corp, 760 Parkside Avenue, STE 211, Brooklyn, New York 11226, United States; EverGauge Science and Technology, ShenZhen, PR China
| | - Handong Liang
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology (Beijing), Beijing 100083, PR China
| | - Yonghui Mao
- Department of Nephrology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing 100730, PR China.
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13
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DeLaney K, Li L. Capillary electrophoresis coupled to MALDI mass spectrometry imaging with large volume sample stacking injection for improved coverage of C. borealis neuropeptidome. Analyst 2019; 145:61-69. [PMID: 31723949 PMCID: PMC6917920 DOI: 10.1039/c9an01883b] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Neuropeptides are important signaling molecules responsible for a wide range of functions within the nervous and neuroendocrine system. However, they are difficult to study due to numerous challenges, most notably their large degree of variability and low abundance in vivo. As a result, effective separation methods with sensitive detection capabilities are necessary for profiling neuropeptides in tissue samples, particularly those of simplified model organisms such as crustaceans. In order to address these challenges, this study utilized a capillary electrophoresis (CE)-matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry imaging (MSI) platform, building upon our previous design for improved neuropeptidomic coverage. The capillary was coated with polyethylenimine (PEI) to reduce peptide adsorption and reverse the electroosmotic flow, and large volume sample stacking (LVSS) was used to load and pre-concentrate 1 μL of sample. The method demonstrated good reproducibility, with lower than 5% relative standard deviation for standards, and a limit of detection of approximately 100 pM for an allatostatin III peptide standard. The method was tested on brain and sinus gland (SG) tissue extracts and enabled detection of over 200 neuropeptides per run. When comparing the number detected in brain extracts in a direct spot, 60-second fractions, and 30-second fractions, the continuous trace collection afforded by the CE-MALDI-MSI platform yielded the largest number of detected neuropeptides. The method was compared to conventional LC-ESI-MS, and though the number of neuropeptides detected by LC-ESI-MS was slightly larger, the two methods were highly complementary, indicating the potential for the CE-MALDI-MSI method to uncover previously undetected neuropeptides in the crustacean nervous system. These results indicate the potential of CE-MALDI-MSI for routine use in neuropeptide research.
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Affiliation(s)
- Kellen DeLaney
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706-1322
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706-1322
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI 53705-2222
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14
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Schachner LF, Ives AN, McGee JP, Melani RD, Kafader JO, Compton PD, Patrie SM, Kelleher NL. Standard Proteoforms and Their Complexes for Native Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:1190-1198. [PMID: 30963455 PMCID: PMC6592724 DOI: 10.1007/s13361-019-02191-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/04/2019] [Accepted: 03/11/2019] [Indexed: 05/09/2023]
Abstract
Native mass spectrometry (nMS) is a technique growing at the interface of analytical chemistry, structural biology, and proteomics that enables the detection and partial characterization of non-covalent protein assemblies. Currently, the standardization and dissemination of nMS is hampered by technical challenges associated with instrument operation, benchmarking, and optimization over time. Here, we provide a standard operating procedure for acquiring high-quality native mass spectra of 30-300 kDa proteins using an Orbitrap mass spectrometer. By describing reproducible sample preparation, loading, ionization, and nMS analysis, we forward two proteoforms and three complexes as possible standards to advance training and longitudinal assessment of instrument performance. Spectral data for five standards can guide assessment of instrument parameters, data production, and data analysis. By introducing this set of standards and protocols, we aim to help normalize native mass spectrometry practices across labs and provide benchmarks for reproducibility and high-quality data production in the years ahead. Graphical abstract.
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Affiliation(s)
- Luis F Schachner
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - Ashley N Ives
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - John P McGee
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - Rafael D Melani
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - Jared O Kafader
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - Philip D Compton
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - Steven M Patrie
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA
| | - Neil L Kelleher
- Departments of Chemistry and Molecular Biosciences, the Chemistry of Life Processes Institute, and the Proteomics Center of Excellence, Northwestern University, 2170 Tech Dr., Silverman Hall, Evanston, IL, 60208, USA.
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15
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Chen CH, Feng H, Guo R, Li P, Laserna AKC, Ji Y, Ng BH, Li SFY, Khan SH, Paulus A, Chen SM, Karger AE, Wenz M, Ferrer DL, Huhmer AF, Krupke A. Intact NIST monoclonal antibody characterization—Proteoforms, glycoforms—Using CE-MS and CE-LIF. ACTA ACUST UNITED AC 2018. [DOI: 10.1080/23312009.2018.1480455] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Chien-Hsun Chen
- Thermo Fisher Scientific, Chromatography and Mass Spectrometry, 355 River Oaks Parkway, San Jose, CA 95134, USA
- Thermo Fisher Scientific, Life Science Solutions, 180 Oyster Point Parkway, South San Francisco, CA 94080, USA
| | - Huatao Feng
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Rui Guo
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Pingjing Li
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Anna Karen C. Laserna
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Ya Ji
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Bao Hui Ng
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Sam Fong Yau Li
- Department of Chemistry, National University of Singapore, Science Drive 3, Singapore S117543, Singapore
| | - Shaheer H. Khan
- Thermo Fisher Scientific, Life Science Solutions, 180 Oyster Point Parkway, South San Francisco, CA 94080, USA
| | - Aran Paulus
- Thermo Fisher Scientific, Chromatography and Mass Spectrometry, 355 River Oaks Parkway, San Jose, CA 95134, USA
| | - Shiaw-Min Chen
- Thermo Fisher Scientific, Life Science Solutions, 180 Oyster Point Parkway, South San Francisco, CA 94080, USA
| | - Achim E. Karger
- Thermo Fisher Scientific, Life Science Solutions, 180 Oyster Point Parkway, South San Francisco, CA 94080, USA
| | - Michael Wenz
- Thermo Fisher Scientific, Life Science Solutions, 180 Oyster Point Parkway, South San Francisco, CA 94080, USA
| | - Daniel Lopez Ferrer
- Thermo Fisher Scientific, Chromatography and Mass Spectrometry, 355 River Oaks Parkway, San Jose, CA 95134, USA
| | - Andreas F. Huhmer
- Thermo Fisher Scientific, Chromatography and Mass Spectrometry, 355 River Oaks Parkway, San Jose, CA 95134, USA
| | - Andreas Krupke
- Thermo Fisher Scientific, Life Science Solutions, 180 Oyster Point Parkway, South San Francisco, CA 94080, USA
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16
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KAWAI T. Recent Studies on Online Sample Preconcentration Methods inCapillary Electrophoresis Coupled with Mass Spectrometry. CHROMATOGRAPHY 2017. [DOI: 10.15583/jpchrom.2017.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Takayuki KAWAI
- Quantitative Biology Center, RIKEN
- Japan Science and Technology Agency, PRESTO
- Graduate School of Frontier Biosciences, Osaka University
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17
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Gamat SN, Fotouhi L, Talebpour Z. The application of electrochemical detection in capillary electrophoresis. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2016. [DOI: 10.1007/s13738-016-1023-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Yin Y, Li G, Guan Y, Huang G. Sheathless interface to match flow rate of capillary electrophoresis with electrospray mass spectrometry using regular-sized capillary. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30 Suppl 1:68-72. [PMID: 27539418 DOI: 10.1002/rcm.7621] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
RATIONALE The flow rate match has been a great challenge when coupling capillary electrophoresis (CE) with electrospray ionization mass spectrometry (ESI-MS). Conventional CE-ESI-MS interfaces used liquid sheath flow, narrowed capillary or additional pressure to meet this requirement; sacrifice of either capillary inner diameter (i.d.) or separation efficiency is often inevitable. Thus, a regular-sized capillary-based sheathless interface would be attractive for flow rate match in CE-MS. METHODS The regular-sized capillary-based CE-MS interface was achieved by coupling CE with induced electrospray ionization (iESI) which was stimulated by the fact that the iESI could both achieve flow rate down to 0.2 μL/min and retain ionization efficiency. The CE-iESI-MS interface was completed with an intact separation capillary, outside the outlet end of which a metal electrode was attached for the application of alternating current (ac) high voltage (HV). RESULTS The feasibility of this CE-iESI-MS interface was demonstrated through the stable total ion chromatograms obtained by continuous CE infusion of tripropylamine with regular-sized capillaries. Tripropylamine and atenolol were separated and detected successfully in phosphate buffer solution (PBS) by CE-iESI-MS using a 50 or 75 μm i.d. capillary. Furthermore, this new interface showed a better signal-to-noise (S/N) of 3 to 7 times enhancement compared with another sheathless CE-ESI-MS interface that using one high voltage for both separation and electrospray when analyzing the mixture of tripropylamine and proline in NH4 OAc buffer. In addition, the reproducibility of this interface gave satisfactory results with relative standard deviation (RSD) in retention time in the range between 1% and 3%. CONCLUSIONS The novel sheathless CE-MS interface introduced here could match conventional electroosmotic flow (EOF) with electrospray which could also preserve the separation efficiency and sensitivity of CE-MS. This newly developed CE-iESI-MS interface was also demonstrated to be effective for different buffers, PBS and NH4 OAc, without any additives such as methanol and acetic acid. Hence, we believe that this sheathless CE-MS interface could be operated with other nonvolatile and volatile buffers. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Yue Yin
- Department of Chemistry, School of Chemistry and Materials Science, University of Science and Technology of China (USTC), Hefei, 230026, China
| | - Gongyu Li
- Department of Chemistry, School of Chemistry and Materials Science, University of Science and Technology of China (USTC), Hefei, 230026, China
| | - Yafeng Guan
- Department of Instrumentation and Analytical Chemistry, Key Laboratory of Separation Science for Analytical Chemistry of CAS, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Guangming Huang
- Department of Chemistry, School of Chemistry and Materials Science, University of Science and Technology of China (USTC), Hefei, 230026, China
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19
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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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20
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Han M, Rock BM, Pearson JT, Rock DA. Intact mass analysis of monoclonal antibodies by capillary electrophoresis—Mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1011:24-32. [DOI: 10.1016/j.jchromb.2015.12.045] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 12/17/2015] [Accepted: 12/20/2015] [Indexed: 12/23/2022]
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21
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Ibáñez C, Simó C, García-Cañas V, Cifuentes A, Castro-Puyana M. Metabolomics, peptidomics and proteomics applications of capillary electrophoresis-mass spectrometry in Foodomics: A review. Anal Chim Acta 2013; 802:1-13. [DOI: 10.1016/j.aca.2013.07.042] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 06/20/2013] [Accepted: 07/17/2013] [Indexed: 01/05/2023]
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22
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Automated method for analysis of tryptophan and tyrosine metabolites using capillary electrophoresis with native fluorescence detection. Anal Bioanal Chem 2013; 405:2451-9. [PMID: 23307134 DOI: 10.1007/s00216-012-6685-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 11/28/2012] [Accepted: 12/20/2012] [Indexed: 02/04/2023]
Abstract
Capillary electrophoresis (CE) with laser-induced native fluorescence (LINF) detection offers the ability to characterize low levels of selected analyte classes, depending on the excitation and emission wavelengths used. Here a new automated CE-LINF system that provides deep ultraviolet (DUV) excitation (224 nm) and variable emission wavelength detection was evaluated for the analysis of small molecule tryptophan- and tyrosine-related metabolites. The optimized instrument design includes several features that increase throughput, lower instrument cost and maintenance, and decrease complexity when compared with earlier systems using DUV excitation. Sensitivity is enhanced by using an ellipsoid detection cell to increase the fluorescence collection efficiency. The limits of detection ranged from 4 to 30 nmol/L for serotonin and tyrosine, respectively. The system demonstrated excellent linearity over several orders of magnitude of concentration and intraday precision from 1-11 % relative standard deviation (RSD). The instrument's performance was validated via tryptophan and serotonin characterization using tissue extracts from the mammalian brain stem, with RSDs of less than 10 % for both metabolites. The flexibility and sensitivity offered by DUV laser excitation and tunable emission enables a broad range of small-volume measurements.
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23
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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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24
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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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25
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Sun L, Zhu G, Li Y, Wojcik R, Yang P, Dovichi NJ. CZE-ESI-MS/MS system for analysis of subnanogram amounts of tryptic digests of a cellular homogenate. Proteomics 2012; 12:3013-9. [PMID: 22888077 DOI: 10.1002/pmic.201200100] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 06/14/2012] [Accepted: 06/18/2012] [Indexed: 12/15/2022]
Abstract
We report the performance of capillary zone electrophoresis coupled with an electrokinetically pumped electrospray interface and an Orbitrap-Velos mass spectrometer for high sensitivity protein analysis. We first investigated the system for quantitation of the tryptic digest of BSA. The system produced outstanding linearity with respect to peak height, number of peptide IDs, and spectral counts across the range of 12 nM to 750 nM (60 amol to 3.5 fmol) of BSA injected. One peptide produced a detection limit of 0.3 nM (1.5 amol) injected. We also analyzed 700 pg of a tryptic digest prepared from a RAW264.7 cell lysate; ten proteins were identified in triplicate analyses after filtering the data with peptide confidence value as high. This sample size corresponds to the protein content of approximately ten eukaryotic cells.
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Affiliation(s)
- Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
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26
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Ramautar R, Heemskerk AAM, Hensbergen PJ, Deelder AM, Busnel JM, Mayboroda OA. CE-MS for proteomics: Advances in interface development and application. J Proteomics 2012; 75:3814-28. [PMID: 22609513 DOI: 10.1016/j.jprot.2012.04.050] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 04/23/2012] [Accepted: 04/30/2012] [Indexed: 12/25/2022]
Abstract
Capillary electrophoresis-mass spectrometry (CE-MS) has emerged as a powerful technique for the analysis of proteins and peptides. Over the past few years, significant progress has been made in the development of novel and more effective interfaces for hyphenating CE to MS. This review provides an overview of these new interfacing techniques for coupling CE to MS, covering the scientific literature from January 2007 to December 2011. The potential of these new CE-MS interfacing techniques is demonstrated within the field of (clinical) proteomics, more specifically "bottom-up" proteomics, by showing examples of the analysis of various biological samples. The relevant papers on CE-MS for proteomics are comprehensively summarized in tables, including, e.g. information on sample type and pretreatment, interfacing and MS detection mode. Finally, general conclusions and future perspectives are provided.
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Affiliation(s)
- Rawi Ramautar
- Biomolecular Mass Spectrometry Unit, Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands.
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Zhao SS, Zhong X, Chen DD. Atmospheric pressure ion lens extends the stable operational region of an electrospray ion source for capillary electrophoresis-mass spectrometry. Electrophoresis 2012; 33:1322-30. [DOI: 10.1002/elps.201100572] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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28
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Bonvin G, Veuthey JL, Rudaz S, Schappler J. Evaluation of a sheathless nanospray interface based on a porous tip sprayer for CE-ESI-MS coupling. Electrophoresis 2012; 33:552-62. [DOI: 10.1002/elps.201100461] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Mishur RJ, Rea SL. Applications of mass spectrometry to metabolomics and metabonomics: detection of biomarkers of aging and of age-related diseases. MASS SPECTROMETRY REVIEWS 2012; 31:70-95. [PMID: 21538458 DOI: 10.1002/mas.20338] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 03/29/2011] [Accepted: 03/29/2011] [Indexed: 05/20/2023]
Abstract
Every 5 years or so new technologies, or new combinations of old ones, seemingly burst onto the science scene and are then sought after until they reach the point of becoming commonplace. Advances in mass spectrometry instrumentation, coupled with the establishment of standardized chemical fragmentation libraries, increased computing power, novel data-analysis algorithms, new scientific applications, and commercial prospects have made mass spectrometry-based metabolomics the latest sought-after technology. This methodology affords the ability to dynamically catalogue and quantify, in parallel, femtomole quantities of cellular metabolites. The study of aging, and the diseases that accompany it, has accelerated significantly in the last decade. Mutant genes that alter the rate of aging have been found that increase lifespan by up to 10-fold in some model organisms, and substantial progress has been made in understanding fundamental alterations that occur at both the mRNA and protein level in tissues of aging organisms. The application of metabolomics to aging research is still relatively new, but has already added significant insight into the aging process. In this review we summarize these findings. We have targeted our manuscript to two audiences: mass spectrometrists interested in applying their technical knowledge to unanswered questions in the aging field, and gerontologists interested in expanding their knowledge of both mass spectrometry and the most recent advances in aging-related metabolomics.
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Affiliation(s)
- Robert J Mishur
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78245, USA.
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Hommerson P, Khan AM, de Jong GJ, Somsen GW. Ionization techniques in capillary electrophoresis-mass spectrometry: principles, design, and application. MASS SPECTROMETRY REVIEWS 2011; 30:1096-1120. [PMID: 21462232 DOI: 10.1002/mas.20313] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 06/03/2010] [Indexed: 05/30/2023]
Abstract
A major step forward in the development and application of capillary electrophoresis (CE) was its coupling to ESI-MS, first reported in 1987. More than two decades later, ESI has remained the principal ionization technique in CE-MS, but a number of other ionization techniques have also been implemented. In this review the state-of-the-art in the employment of soft ionization techniques for CE-MS is presented. First the fundamentals and general challenges of hyphenating conventional CE and microchip electrophoresis with MS are outlined. After elaborating on the characteristics and role of ESI, emphasis is put on alternative ionization techniques including sonic spray ionization (SSI), thermospray ionization (TSI), atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI), matrix-assisted laser desorption ionization (MALDI) and continuous-flow fast atom bombardment (CF-FAB). The principle of each ionization technique is outlined and the experimental set-ups of the CE-MS couplings are described. The strengths and limitations of each ionization technique with respect to CE-MS are discussed and the applicability of the various systems is illustrated by a number of typical examples.
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MESH Headings
- Electrophoresis, Capillary/instrumentation
- Electrophoresis, Capillary/methods
- Equipment Design/instrumentation
- Equipment Design/methods
- Pharmaceutical Preparations/analysis
- Pharmaceutical Preparations/chemistry
- Proteins/analysis
- Proteins/chemistry
- Spectrometry, Mass, Electrospray Ionization/instrumentation
- Spectrometry, Mass, Electrospray Ionization/methods
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/instrumentation
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
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Affiliation(s)
- Paul Hommerson
- Department of Biomedical Analysis, Utrecht University, PO Box 80082, 3508 TB Utrecht, The Netherlands.
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31
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Zhong X, Maxwell EJ, Chen DD. Mass Transport in a Micro Flow-Through Vial of a Junction-at-the-Tip Capillary Electrophoresis-Mass Spectrometry Interface. Anal Chem 2011; 83:4916-23. [DOI: 10.1021/ac200636y] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xuefei Zhong
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
| | - E. Jane Maxwell
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
| | - David D.Y. Chen
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
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Wojcik R, Dada OO, Sadilek M, Dovichi NJ. Simplified capillary electrophoresis nanospray sheath-flow interface for high efficiency and sensitive peptide analysis. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:2554-60. [PMID: 20740530 DOI: 10.1002/rcm.4672] [Citation(s) in RCA: 161] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We report a simple nanospray sheath-flow interface for capillary electrophoresis. This interface relies on electrokinetic flow to drive both the separation and the electrospray; no mechanical pump is used for the sheath flow. This system was interfaced with an LCQ mass spectrometer. The best results were observed with a 2-microm diameter emitter tip and a 1-mm spacing between the separation capillary tip and the emitter tip. Under these conditions, mass detection limits (3sigma) of 100 amol were obtained for insulin receptor fragment 1142-1153. The separation efficiency exceeded 200,000 plates for this compound. The relative standard deviation generated during continual infusion of a 50 microM solution of angiotensin II was 2% for the total ion count and 3% for the extracted ion count over a 40-min period. Finally, the interface was also demonstrated for negative ion mode.
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Affiliation(s)
- Roza Wojcik
- Department of Chemistry, University of Washington, Seattle, WA 98195-1700, USA
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Maxwell EJ, Zhong X, Zhang H, van Zeijl N, Chen DDY. Decoupling CE and ESI for a more robust interface with MS. Electrophoresis 2010; 31:1130-1137. [DOI: 10.1002/elps.200900517] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Klepárník K, Otevřel M. Analyte transport in liquid junction nano-electrospray interface between capillary electrophoresis and mass spectrometry. Electrophoresis 2010; 31:879-85. [DOI: 10.1002/elps.200900544] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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35
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Shi LH, Jin YX, Moon DC, Kim SK, Park SR. A sheathless CE/ESI-MS interface with an ionophore membrane-packed electro-conduction channel. Electrophoresis 2009; 30:1661-9. [DOI: 10.1002/elps.200800664] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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36
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Li FA, Huang JL, Her GR. Chip-CE/MS using a flat low-sheath-flow interface. Electrophoresis 2008; 29:4938-43. [DOI: 10.1002/elps.200800271] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Maxwell EJ, Chen DD. Twenty years of interface development for capillary electrophoresis–electrospray ionization–mass spectrometry. Anal Chim Acta 2008; 627:25-33. [DOI: 10.1016/j.aca.2008.06.034] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Revised: 06/13/2008] [Accepted: 06/19/2008] [Indexed: 11/15/2022]
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Gaspar A, Englmann M, Fekete A, Harir M, Schmitt-Kopplin P. Trends in CE-MS 2005–2006. Electrophoresis 2008; 29:66-79. [DOI: 10.1002/elps.200700721] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
Over the past decade, chemical cytometry performed by capillary electrophoresis (CE) has become increasingly valuable as a bioanalytical tool to quantify analytes from single cells. However, extensive use of CE-based chemical cytometry has been hindered by the relatively low throughput for the analysis of single adherent cells. In order to overcome the low throughput of CE-based analysis of adherent cells and increase its utility in evaluating cellular attributes, new higher throughput methods are needed. Integration of a coaxial buffer exchange system with CE-based chemical cytometry increased the rate of serial analyses of cells. In the designed system, fluid flow through a tube coaxial to the separation capillary was used to supply electrophoretic buffer to the capillary. This sheath or coaxial fluid was turned off between analysis of cells and on during cell sampling and electrophoresis. Thus, living cells were not exposed to the nonphysiologic electrophoretic buffer prior to lysis. Key parameters of the system such as the relative capillary-sheath positions, buffer flow velocities, and the cell chamber design were optimized. To demonstrate the utility of the system, rat basophilic leukemic cells loaded with Oregon green and fluorescein were serially lysed and loaded into a capillary. Separation of the contents of 20 cells at a rate of 0.5 cells/min was demonstrated.
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Affiliation(s)
- Paul J Marc
- Department of Biomedical Engineering, University of California, Irvine, California 92697, USA
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Li J, Richards JC. Application of capillary electrophoresis mass spectrometry to the characterization of bacterial lipopolysaccharides. MASS SPECTROMETRY REVIEWS 2007; 26:35-50. [PMID: 16967446 DOI: 10.1002/mas.20105] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Capillary electrophoresis (CE) is a high-resolution technique for the separation of complex biological mixtures and has been widely applied to biological analyses. The coupling of capillary electrophoresis with mass spectrometry (MS) provides a powerful approach for rapid identification of target analytes present at trace levels in biological matrices, and for structural characterization of complex biomolecules. Here we review the analytical potential of combined capillary electrophoresis electrospray mass spectrometry (CE-MS) for the analysis of bacterial lipopolysaccharides (LPS). This hyphened methodology facilitates the determination of closely related LPS glycoform and isoform families by exploiting differences in their unique molecular conformations and ionic charge distributions by electrophoretic separation. On-line CE-MS also provides an additional avenue to improve detection limits, which has been successfully applied to directly probe oligosaccharide LPS glycoform populations of bacteria isolated from infected animal models without the need for further passage.
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Affiliation(s)
- Jianjun Li
- Institute for Biological Sciences, National Research Council, Ottawa, ON, Canada K1A 0R6.
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Mao X, Chu IK, Lin B. A sheath-flow nanoelectrospray interface of microchip electrophoresis MS for glycoprotein and glycopeptide analysis. Electrophoresis 2006; 27:5059-67. [PMID: 17117389 DOI: 10.1002/elps.200600349] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Microchip was coupled with MS through a stable, sensitive, and controllable sheath-flow nanoelectrospray (nES) interface for glycoprotein and glycopeptide analysis. The nano-ESI (nESI) was made with a delivery capillary, a commercial nES capillary, and a stainless steel (SS) tube which were connected together through a tee unit. High voltage for nES was applied on the SS tube and the commercial nES capillary was used as nES emitter. The delivery capillary was attached to the microchannel for delivering liquid from microchip to the nESI source. The flow rate of sheath liquid was optimized to be 100-200 nL/min which largely reduced the sample dilution. The detection limit of peptides on this microchip/MS platform was at femtomole level. Glycoprotein and glycopeptides were also successfully analyzed on the platform. All the glycoforms and glycopeptides of ribonuclease B (RNase B) were identified with this method. Some structures of the glycopeptides from RNase B were further characterized with MS/MS on the microchip, coupled with a quadrupole IT-MS.
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Affiliation(s)
- Xiuli Mao
- Dalian Institute of Chemical Physics, Chinese Academy of Scienes, Dalian, PR China
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42
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Lapainis T, Scanlan C, Rubakhin SS, Sweedler JV. A multichannel native fluorescence detection system for capillary electrophoretic analysis of neurotransmitters in single neurons. Anal Bioanal Chem 2006; 387:97-105. [PMID: 17047942 DOI: 10.1007/s00216-006-0775-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Revised: 08/08/2006] [Accepted: 08/10/2006] [Indexed: 10/24/2022]
Abstract
A laser-induced native fluorescence detection system optimized for analysis of indolamines and catecholamines by capillary electrophoresis is described. A hollow-cathode metal vapor laser emitting at 224 nm is used for fluorescence excitation, and the emitted fluorescence is spectrally distributed by a series of dichroic beam-splitters into three wavelength channels: 250-310 nm, 310-400 nm, and >400 nm. A separate photomultiplier tube is used for detection of the fluorescence in each of the three wavelength ranges. The instrument provides more information than a single-channel system, without the complexity associated with a spectrograph/charge-coupled device-based detector. With this instrument, analytes can be separated and identified not only on the basis of their electrophoretic migration time but also on the basis of their multichannel signature, which consists of the ratios of relative fluorescence intensities detected in each wavelength channel. The 224-nm excitation channel resulted in a detection limit of 40 nmol L-1 for dopamine. The utility of this instrument for single-cell analysis was demonstrated by the detection and identification of the neurotransmitters in serotonergic LPeD1 and dopaminergic RPeD1 neurons, isolated from the central nervous system of the well-established neurobiological model Lymnaea stagnalis. Not only can this system detect neurotransmitters in these individual neurons with S/N>50, but analyte identity is confirmed on the basis of spectral characteristics.
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Affiliation(s)
- T Lapainis
- Department of Chemistry and the Beckman Institute, University of Illinois, 600 S. Matthews Ave., Box 63-5, Urbana, IL 61801, USA
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43
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Smyth WF. Recent applications of capillary electrophoresis-electrospray ionisation-mass spectrometry in drug analysis. Electrophoresis 2006; 27:2051-62. [PMID: 16637016 DOI: 10.1002/elps.200500524] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This review considers applications in 2004-2005 of capillary electrophoresis-electrospray ionisation-mass spectrometry (CE-ESI-MS) to the detection and determination of small molecular mass drug molecules, taken from the Web of Knowledge database. The molecules of small molecular mass less than 1000 Da are chosen according to selected structural classes in which they give ESI signals primarily as [M + H](+) ions. These structural classes are drugs with amine-containing side chains, drugs with N-containing saturated ring structures, 1,4-benzodiazepines, other heterocyclic hypnotics, steroids, bioactive compounds containing phenolic groups, and miscellaneous molecules. Details are given on the fragmentations, where available, that these ionic species exhibit in-source and in ion-trap, triple quadrupole and time-of flight mass spectrometers. The review then gives a critical evaluation of these recent CE-ESI-MS analytical methods for the detection and determination of these small molecular mass drug molecules. Analytical information on, for example, sample concentration techniques, CE separation conditions, recoveries from biological media and limits of detection are provided.
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Affiliation(s)
- W Franklin Smyth
- School of Biomedical Sciences, University of Ulster, Coleraine, UK.
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Klampfl CW. Recent advances in the application of capillary electrophoresis with mass spectrometric detection. Electrophoresis 2006; 27:3-34. [PMID: 16315165 DOI: 10.1002/elps.200500523] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This review gives an overview of applications of CE coupled to MS detection published in the literature of the last three years. The works discussed in this paper comprise a wide range of different fields of application. These include important sections such as the analysis of biomolecules, the analysis of pharmaceuticals and their metabolites in different matrices, environmental analysis, and also investigations on the composition of technical products.
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Affiliation(s)
- Christian W Klampfl
- Institute of Analytical Chemistry, Johannes Kepler University Linz, Linz, Austria.
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2005; 40:973-84. [PMID: 16034836 DOI: 10.1002/jms.808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
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Liu CC, Alary JF, Vollmerhaus P, Kadkhodayan M. Design, optimisation, and evaluation of a sheath flow interface for automated capillary electrophoresis-electrospray-mass spectrometry. Electrophoresis 2005; 26:1366-75. [PMID: 15761922 DOI: 10.1002/elps.200410133] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A sheath-flow capillary electrophoresis-mass spectrometry (CE-MS) system utilizing a fully integrated large-bore stainless-steel emitter electrode tapered at the end for micro-ionspray operation has been developed and evaluated. A separation capillary with an outer diameter of up to 360 microm was inserted into the electrode thus forming a void volume of less than 15 nL between the capillary end and the electrospray ionisation (ESI) tip. The sheath liquid, usually methanol-water (80:20) with 0.1% formic acid for positive ion mode or methanol for negative ion mode, was delivered at 0.5-1.0 microL/min. Unlike previously reported CE-MS interfaces, the CE-MS probe was incorporated directly onto an Applied Biosystems/MDS SCIEX orthogonal-spray Turbo "V" ion source for ease of use and automatic operation. This integration enables fast and facile coupling and replacement of the separation capillary without interrupting the ion source configuration, and the sheath liquid supply. The reusable electrospray electrode was precisely fabricated and aligned with the length of the nebulizing gas tube for improved reproducibility. Automation was achieved through software control of both CE and tandem MS (MS/MS) for unattended batch sample analysis. The system was evaluated for attomole- to low femtomole-level profiling of model peptides and protein mixtures, bisphosphates, as well as antiviral nucleosidic drugs in cellular extracts.
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