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Huge BJ, Kerr CM, Wanigasinghe S, Champion MM, Dovichi NJ. Optimized sample buffer for dispersed, high-resolution capillary zone electrophoretic separation of Escherichia coli B. Sci Rep 2023; 13:22269. [PMID: 38097688 PMCID: PMC10721931 DOI: 10.1038/s41598-023-49669-y] [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: 09/01/2023] [Accepted: 12/11/2023] [Indexed: 12/17/2023] Open
Abstract
Capillary zone electrophoresis (CZE) is a powerful tool for high resolution chemical separations. Applying CZE to microbial samples may facilitate a deeper understanding of bacterial physiology and behavior. However, the study of complex microbial samples has been limited by the uncontrolled hetero-aggregation of bacterial cells under an applied electric field. We tested a wide range of sample buffers and buffer additives for the optimization of bacterial CZE separations using a 20 mM Tris-HCl background electrolyte. By modifying the sample buffer, but not the background electrolyte, we retain constant separation conditions, which aids in the comparison of the sample buffer additives. We report optimized methods for automated CZE separation and simultaneous fractionation of Escherichia coli B, which is one of the two most widely used wild-type strains. A modified sample buffer containing neutral salts and the addition of glycerol produced a 20-fold increase in loading capacity and a reduction in peak width/broadening of 86% in comparison to previously reported work. In addition, the glycerol-modified sample buffer appears to reduce the persistent aggregation and adhesion to the capillary walls during electrophoretic separations of complex environmental microbiota.
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Affiliation(s)
- Bonnie Jaskowski Huge
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Caitlin M Kerr
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Sacheela Wanigasinghe
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Matthew M Champion
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.
- Berthiaume Institute for Precision Health, University of Notre Dame, Notre Dame, IN, 46556, USA.
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.
- Berthiaume Institute for Precision Health, University of Notre Dame, Notre Dame, IN, 46556, USA.
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Booth PPM, Lamb DT, Anderson JP, Furtaw MD, Kennedy RT. Capillary electrophoresis Western blot using inkjet transfer to membrane. J Chromatogr A 2022; 1679:463389. [PMID: 35933772 DOI: 10.1016/j.chroma.2022.463389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/15/2022] [Accepted: 07/29/2022] [Indexed: 10/16/2022]
Abstract
Traditional Western blots are commonly used to separate and assay proteins; however, they have limitations including a long, cumbersome process and large sample requirements. Here, we describe a system for Western blotting where capillary gel electrophoresis is used to separate sodium dodecyl sulfate-protein complexes. The capillary outlet is threaded into a piezoelectric inkjetting head that deposits the separated proteins in a quasi-continuous stream of <100 pL droplets onto a moving membrane. Through separations at 400 V/cm and protein capture on a membrane moving at 2 mm/min, we are able to detect actin with a limit of detection at 8 pM, or an estimated 5 fg injected. Separation and membrane capture of sample containing 10 proteins ranging in molecular weights from 11 - 250 kDa was achieved in 15 min. The system was demonstrated with Western blots for actin, β-tubulin, ERK1/2, and STAT3 in human A431 epidermoid carcinoma cell lysate.
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Insights from capillary electrophoresis approaches for characterization of monoclonal antibodies and antibody drug conjugates in the period 2016–2018. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1122-1123:1-17. [DOI: 10.1016/j.jchromb.2019.05.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 12/31/2022]
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Huge BJ, Champion MM, Dovichi NJ. Capillary Zone Electrophoresis with Fraction Collection for Separation, Culturing, and Identification of Bacteria from an Environmental Microbiome. Anal Chem 2019; 91:4649-4655. [PMID: 30801180 DOI: 10.1021/acs.analchem.8b05984] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Capillary zone electrophoresis (CZE) can produce high-resolution separations of biological samples, including microbial mixtures. The study of complex populations of microorganisms using CZE is limited because most detectors have limited sensitivity, are destructive, and provide limited information for microbial identification. To address these issues, we developed an integrated capillary zone electrophoresis apparatus to fractionate bacteria from complex mixtures. We deposited fractions onto nutrient agar in a Petri dish for microbial culturing, and we subjected the observed colonies to Sanger sequencing of a phylogenetic marker, the 16S rRNA gene, for microbial identification. We separated and cultured both a single bacteria species, the model Gram-negative organism Escherichia coli, and a complex environmental isolate of primary sewage effluent. Sequence analysis of the 16S rRNA genes from this mixture identified 15 ± 5 distinct bacterial species per run. This approach requires minimal manipulation of microbial populations and combines electrophoretic fractionation of bacterial cells with automated collection for accurate identification of species. This approach should be applicable to microorganisms in general and may enable discrimination of physiologically different cells in complex assemblages, such as in microbiome samples.
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LI ZY, SUN K, ZHANG XY, LIU SQ, JIANG L, REN NQ. Advance in Microfluidic Devices for Fractionation of DNA Fragments. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2016. [DOI: 10.1016/s1872-2040(16)60922-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Biacchi M, Bhajun R, Saïd N, Beck A, François YN, Leize-Wagner E. Analysis of monoclonal antibody by a novel CE-UV/MALDI-MS interface. Electrophoresis 2014; 35:2986-95. [PMID: 25070377 DOI: 10.1002/elps.201400276] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/01/2014] [Accepted: 07/08/2014] [Indexed: 12/16/2022]
Abstract
mAbs are highly complex proteins that present a wide range of microheterogeneity that requires multiple analytical methods for full structure assessment and quality control. As a consequence, the characterization of mAbs on different levels is particularly product- and time-consuming. CE-MS couplings, especially to MALDI, appear really attractive methods for the characterization of biological samples. In this work, we report the last instrumental development and performance of the first totally automated off-line CE-UV/MALDI-MS/MS. This interface is based on the removal of the original UV cell of the CE apparatus, modification of the spotting device geometry, and creation of an integrated delivery matrix system. The performance of the method was evaluated with separation of five intact proteins and a tryptic digest mixture of nine proteins. Intact protein application shows the acquisition of electropherograms with high resolution and high repeatability. In the peptide mapping approach, a total number of 154 unique identified peptides were characterized using MS/MS spectra corresponding to average sequence coverage of 64.1%. Comparison with NanoLC/MALDI-MS/MS showed complementarity at the peptide level with an increase of 42% when using CE/MALDI-MS coupling. Finally, this work represents the first analysis of intact mAb charge variants by CZE using an MS detection. Moreover, using a peptide mapping approach CE-UV/MALDI-MS/MS fragmentation allowed 100% sequence coverage of the light chain and 92% of the heavy chain, and the separation of four major glycosylated peptides and their structural characterization.
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Affiliation(s)
- Michael Biacchi
- Laboratoire de Spectrométrie de Masse des Interactions et des Systèmes (LSMIS), CNRS-UMR 7140, Université de Strasbourg, Strasbourg, France
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7
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Huge BJ, Flaherty RJ, Dada OO, Dovichi NJ. Capillary electrophoresis coupled with automated fraction collection. Talanta 2014; 130:288-93. [PMID: 25159411 DOI: 10.1016/j.talanta.2014.07.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 10/25/2022]
Abstract
A fraction collector based on a drop-on-demand ink-jet printer was developed to interface capillary zone electrophoresis with a 96 well microtiter plate. We first evaluated the performance of the collector by using capillary zone electrophoresis to analyze a 1mM solution of tetramethylrhodamine; a fluorescent microtiter plate reader was then used to detect the analyte and characterize fraction carryover between wells. Relative standard deviation in peak height was 20% and the relative standard deviation in migration time was 1%. The mean and standard deviation of the tetramethylrhodamine peak width was 5 ± 1 s and likely limited by the 4-s period between droplet deposition. We next injected a complex mixture of DNA fragments and used real-time PCR to quantify the product in a CE-SELEX experiment. The reconstructed electrophoretic peak was 27 s in duration. Finally, we repeated the experiment in the presence of a 30-µM thrombin solution under CE-SELEX conditions; fractions were collected and next-generation sequencing was used to characterize the DNA binders. Over 25,000 sequences were identified with close matches to known thrombin binding aptamers.
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Affiliation(s)
- Bonnie Jaskowski Huge
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Ryan J Flaherty
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Oluwatosin O Dada
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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Zhong X, Zhang Z, Jiang S, Li L. Recent advances in coupling capillary electrophoresis-based separation techniques to ESI and MALDI-MS. Electrophoresis 2013; 35:1214-25. [PMID: 24170529 DOI: 10.1002/elps.201300451] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 10/14/2013] [Accepted: 10/15/2013] [Indexed: 01/13/2023]
Abstract
Coupling CE-based separation techniques to MS creates a powerful platform for analysis of a wide range of biomolecules from complex samples because it combines the high separation efficiency of CE and the sensitivity and selectivity of MS detection. ESI and MALDI, as the most common soft ionization techniques employed for CE and MS coupling, offer distinct advantages for biomolecular characterization. This review is focused primarily on technological advances in combining CE and chip-based CE with ESI and MALDI-MS detection in the past five years. Selected applications in the analyses of metabolites, peptides, and proteins with recently developed CE-MS platforms are also highlighted.
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Affiliation(s)
- Xuefei Zhong
- School of Pharmacy, University of Wisconsin, Madison, WI, USA
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9
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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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10
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Zeng H, Weng Y, Ikeda S, Nakagawa Y, Nakajima H, Uchiyama K. Accurate and Highly Reproducible Picoliter Injection System for Capillary Electrophoresis. Anal Chem 2012; 84:10537-42. [DOI: 10.1021/ac302353q] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Hulie Zeng
- Department of Applied Chemistry, Graduate School of
Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo 192-0397, Japan
| | - Ying Weng
- Department of Applied Chemistry, Graduate School of
Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo 192-0397, Japan
| | - Saori Ikeda
- Department of Applied Chemistry, Graduate School of
Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo 192-0397, Japan
| | - Yuri Nakagawa
- Department of Applied Chemistry, Graduate School of
Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo 192-0397, Japan
| | - Hizuru Nakajima
- Department of Applied Chemistry, Graduate School of
Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo 192-0397, Japan
| | - Katsumi Uchiyama
- Department of Applied Chemistry, Graduate School of
Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo 192-0397, Japan
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Zhang Z, Ye H, Wang J, Hui L, Li L. Pressure-assisted capillary electrophoresis coupling with matrix-assisted laser desorption/ionization-mass spectrometric imaging for quantitative analysis of complex peptide mixtures. Anal Chem 2012; 84:7684-91. [PMID: 22891936 DOI: 10.1021/ac300628s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Herein, we report a pressure-assisted capillary electrophoresis-mass spectrometric imaging (PACE-MSI) platform for peptide analysis. This new platform has addressed the sample diffusion and peak splitting problems that appeared in our previous groove design, and it enables homogeneous deposition of the CE trace for high-throughput MALDI imaging. In the coupling of CE to MSI, individual peaks (m/z) can be visualized as discrete colored image regions and extracted from the MS imaging data, thus eliminating issues with peak overlapping and reducing reliance on an ultrahigh mass resolution mass spectrometer. Through a PACE separation, 46 tryptic peptides from bovine serum albumin and 150 putative neuropeptides from the pericardial organs of a model organism blue crab Callinectes sapidus were detected from the MALDI MS imaging traces, enabling a 4- to 6-fold increase of peptide coverage as compared with direct MALDI MS analysis. For the first time, quantitation with high accuracy was obtained using PACE-MSI for both digested tryptic peptides and endogenous neuropeptides from complex biological samples in combination with isotopic formaldehyde labeling. Although MSI is typically employed in tissue imaging, we show in this report that it offers a unique tool for quantitative analysis of complex trace-level analytes with CE separation. These results demonstrate a great potential of the PACE-MSI platform for enhanced quantitative proteomics and neuropeptidomics.
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Affiliation(s)
- Zichuan Zhang
- School of Pharmacy, University of Wisconsin, Madison, 53705, United States
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Chen F, Lin Z, Zheng Y, Zeng H, Nakajima H, Uchiyama K, Lin JM. Development of an automatic multi-channel ink-jet ejection chemiluminescence system and its application to the determination of horseradish peroxidase. Anal Chim Acta 2012; 739:77-82. [DOI: 10.1016/j.aca.2012.06.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 06/03/2012] [Accepted: 06/12/2012] [Indexed: 10/28/2022]
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13
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Zhu X, Zheng Q, Yang H, Cai J, Huang L, Duan Y, Xu Z, Cen P. Recent advances in inkjet dispensing technologies: applications in drug discovery. Expert Opin Drug Discov 2012; 7:761-70. [DOI: 10.1517/17460441.2012.697892] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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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: 64] [Impact Index Per Article: 5.3] [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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15
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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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Wang J, Ye H, Zhang Z, Xiang F, Girdaukas G, Li L. Advancing matrix-assisted laser desorption/ionization-mass spectrometric imaging for capillary electrophoresis analysis of peptides. Anal Chem 2011; 83:3462-9. [PMID: 21417482 DOI: 10.1021/ac200708f] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this work, the utilization of matrix-assisted laser desorption/ionization-mass spectrometric imaging (MALDI-MSI) for capillary electrophoresis (CE) analysis of peptides based on a simple and robust off-line interface has been investigated. The interface involves sliding the CE capillary distal end within a machined groove on a MALDI sample plate, which is precoated with a thin layer of matrix for continuous sample deposition. MALDI-MSI by time of flight (TOF)/TOF along the CE track enables high-resolution and high-sensitivity detection of peptides, allowing the reconstruction of a CE electropherogram while providing accurate mass measurements and structural identification of molecules. Neuropeptide standards and their H/D isotopic formaldehyde-labeled derivatives were analyzed using this new platform. Normalized intensity ratios of individual ions extracted from the CE trace were compared to MALDI-MS direct analysis and the theoretical ratios. The CE-MALDI-MSI results show potential for sensitive and quantitative analysis of peptide mixtures spanning a wide dynamic range.
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Affiliation(s)
- Junhua Wang
- School of Pharmacy, University of Wisconsin-Madison, 53705, United States
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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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Wang J, Zhang Y, Xiang F, Zhang Z, Li L. Combining capillary electrophoresis matrix-assisted laser desorption/ionization mass spectrometry and stable isotopic labeling techniques for comparative crustacean peptidomics. J Chromatogr A 2010; 1217:4463-70. [PMID: 20334868 PMCID: PMC2882495 DOI: 10.1016/j.chroma.2010.02.084] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 02/23/2010] [Accepted: 02/26/2010] [Indexed: 11/27/2022]
Abstract
Herein we describe a sensitive and straightforward off-line capillary electrophoresis (CE) matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) interface in conjunction with stable isotopic labeling (SIL) technique for comparative neuropeptidomic analysis in crustacean model organisms. Two SIL schemes, including a binary H/D formaldehyde labeling technique and novel, laboratory-developed multiplexed dimethylated leucine-based isobaric tagging reagents, have been evaluated in these proof-of-concept experiments. We employ these isotopic labeling techniques in conjunction with CE-MALDI-MS for quantitative peptidomic analyses of the pericardial organs isolated from two crustacean species, the European green crab Carcinus maenas and the blue crab Callinectes sapidus. Isotopically labeled peptide pairs are found to co-migrate in CE fractions and quantitative changes in relative abundances of peptide pairs are obtained by comparing peak intensities of respective peptide pairs. Several neuropeptide families exhibit changes in response to salinity stress, suggesting potential physiological functions of these signaling peptides.
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Affiliation(s)
- Junhua Wang
- School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53705-2222, USA.
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Peš O, Preisler J. Off-line coupling of microcolumn separations to desorption mass spectrometry. J Chromatogr A 2010; 1217:3966-77. [DOI: 10.1016/j.chroma.2010.02.058] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 02/22/2010] [Accepted: 02/24/2010] [Indexed: 01/13/2023]
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