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Forbes TP, Dixon RB, Muddiman DC, Degertekin FL, Fedorov AG. Characterization of charge separation in the Array of Micromachined UltraSonic Electrospray (AMUSE) ion source for mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2009; 20:1684-7. [PMID: 19525123 PMCID: PMC2769925 DOI: 10.1016/j.jasms.2009.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Revised: 05/04/2009] [Accepted: 05/08/2009] [Indexed: 05/23/2023]
Abstract
An initial investigation into the effects of charge separation in the Array of Micromachined UltraSonic Electrospray (AMUSE) ion source is reported to gain understanding of ionization mechanisms and to improve analyte ionization efficiency and operation stability. In RF-only mode, AMUSE ejects, on average, an equal number of slightly positive and slightly negative charged droplets due to random charge fluctuations, providing inefficient analyte ionization. Charge separation at the nozzle orifice is achieved by the application of an external electric field. By bringing the counter electrode close to the nozzle array, strong electric fields can be applied at relatively low DC potentials. It has been demonstrated, through a number of electrode/electrical potential configurations, that increasing charge separation leads to improvement in signal abundance, signal-to-noise ratio, and signal stability.
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Affiliation(s)
- Thomas P. Forbes
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - R. Brent Dixon
- W.M. Keck FT-ICR Mass Spectrometry Laboratory, North Carolina State University, Raleigh, North Carolina 27695
| | - David C. Muddiman
- W.M. Keck FT-ICR Mass Spectrometry Laboratory, North Carolina State University, Raleigh, North Carolina 27695
| | - F. Levent Degertekin
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Andrei G. Fedorov
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
- Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332
- Authors for Correspondence, Andrei G. Fedorov, Ph.D., G. W. Woodruff School of Mechanical Engineering, Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, Phone: 404-385-1356, Fax: 404-894-8496,
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52
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Zhou Y, Shen H, Yi T, Wen D, Pang N, Liao J, Liu H. Synergistic design of electric field and membrane in facilitating continuous adsorption for cleanup and enrichment of proteins in direct ESI-MS analysis. Anal Chem 2009; 80:8920-9. [PMID: 18954078 DOI: 10.1021/ac800816k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We designed and fabricated a novel microdevice to facilitate continuous adsorption phenomena for biological sample preparation. Using the device, we also developed an online, highly integrated, multifunctional strategy, with a promise of accepting a large volume of crude tissue extracts with the end point generation of a reliable MS identification within 20 min. Under an external electric field, charged membranes can adsorb multiple layers of proteins, which exceed the capacity limit of common resins or membranes. It enlarges sample loading and trapping efficiency, thus bypasses the tradeoff between sample capacity and downstream detection sensitivity. This integrated approach, formed by synergistic utilization among electric field, membrane, and fluidic handling at the microscale, reduces the overall complexity of crude samples in one step for direct MS analysis. The sample preparation goals, including enrichment, desalting, removal of noncharged contaminants, and initial fractionation, can be rapidly performed in a single device. The strategy facilitates reproducible MS quantification by circumventing traditional laborious and time-consuming sample preparation steps. In addition, MEPD extended the ion trap linear dynamic range from 2 to at least 4 orders of magnitude by eliminating ion suppression effect, enriching target analyte(s), and decreasing sample loss during integrated sample preparation.
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Affiliation(s)
- Yu Zhou
- Beijing National Laboratory for Molecular Sciences, Key Lab of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Inst. of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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53
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Lazar IM. Recent advances in capillary and microfluidic platforms with MS detection for the analysis of phosphoproteins. Electrophoresis 2009; 30:262-75. [PMID: 19156662 DOI: 10.1002/elps.200800427] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Reversible protein phosphorylation represents a key regulatory mechanism that triggers essential cellular signaling events. The large-scale characterization of protein phosphorylation in a cell represents, therefore, the objective of many biological studies that aim at elucidating the complex signaling pathways that are involved in the progression and/or regression of a disease. The recent implementation of novel MS detection strategies has significantly advanced the capabilities for interrogating the complex cellular phosphoproteome. Simultaneously, the current advent of miniaturized technologies has clearly demonstrated the superior performance of microfluidic instrumentation for bioanalytical and biological applications that cope with speed, sensitivity and throughput-related demands. This review aims at providing an update on the latest developments regarding the interfacing of microfluidic devices with MS detection for exploring the challenging area of phosphoproteomics.
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Affiliation(s)
- Iulia M Lazar
- Virginia Bioinformatics Institute and Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
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54
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Hoffmann P, Eschner M, Fritzsche S, Belder D. Spray Performance of Microfluidic Glass Devices with Integrated Pulled Nanoelectrospray Emitters. Anal Chem 2009; 81:7256-61. [DOI: 10.1021/ac9015038] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Peter Hoffmann
- University of Leipzig, Institute of Analytical Chemistry, Johannisallee 29, 04103 Leipzig, Germany
| | - Markus Eschner
- University of Leipzig, Institute of Analytical Chemistry, Johannisallee 29, 04103 Leipzig, Germany
| | - Stefanie Fritzsche
- University of Leipzig, Institute of Analytical Chemistry, Johannisallee 29, 04103 Leipzig, Germany
| | - Detlev Belder
- University of Leipzig, Institute of Analytical Chemistry, Johannisallee 29, 04103 Leipzig, Germany
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55
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Lee J, Soper SA, Murray KK. Microfluidics with MALDI analysis for proteomics--a review. Anal Chim Acta 2009; 649:180-90. [PMID: 19699392 DOI: 10.1016/j.aca.2009.07.037] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 07/13/2009] [Accepted: 07/15/2009] [Indexed: 01/01/2023]
Abstract
Various microfluidic devices have been developed for proteomic analyses and many of these have been designed specifically for mass spectrometry detection. In this review, we present an overview of chip fabrication, microfluidic components, and the interfacing of these devices to matrix-assisted laser desorption ionization (MALDI) mass spectrometry. These devices can be directly coupled to the mass spectrometer for on-line analysis in real-time, or samples can be analyzed on-chip or deposited onto targets for off-line readout. Several approaches for combining microfluidic devices with analytical functions such as sample cleanup, digestion, and separations with MALDI mass spectrometry are discussed.
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Affiliation(s)
- Jeonghoon Lee
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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56
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Ahmed FE. The role of capillary electrophoresis–mass spectrometry to proteome analysis and biomarker discovery. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:1963-81. [DOI: 10.1016/j.jchromb.2009.05.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2008] [Revised: 04/24/2009] [Accepted: 05/10/2009] [Indexed: 01/25/2023]
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57
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Fidalgo L, Whyte G, Ruotolo B, Benesch J, Stengel F, Abell C, Robinson C, Huck W. Coupling Microdroplet Microreactors with Mass Spectrometry: Reading the Contents of Single Droplets Online. Angew Chem Int Ed Engl 2009; 48:3665-8. [DOI: 10.1002/anie.200806103] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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58
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Fidalgo L, Whyte G, Ruotolo B, Benesch J, Stengel F, Abell C, Robinson C, Huck W. Coupling Microdroplet Microreactors with Mass Spectrometry: Reading the Contents of Single Droplets Online. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200806103] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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59
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Lee J, Soper SA, Murray KK. Microfluidic chips for mass spectrometry-based proteomics. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:579-93. [PMID: 19373851 DOI: 10.1002/jms.1585] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Microfluidic devices coupled to mass spectrometers have emerged as excellent tools for solving the complex analytical challenges associated with the field of proteomics. Current proteome identification procedures are accomplished through a series of steps that require many hours of labor-intensive work. Microfluidics can play an important role in proteomic sample preparation steps prior to mass spectral identification such as sample cleanup, digestion, and separations due to its ability to handle small sample quantities with the potential for high-throughput parallel analysis. To utilize microfluidic devices for proteomic analysis, an efficient interface between the microchip and the mass spectrometer is required. This tutorial provides an overview of the technologies and applications of microfluidic chips coupled to mass spectrometry for proteome analysis. Various approaches for combining microfluidic devices with electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) are summarized and applications of chip-based separations and digestion technologies to proteomic analysis are presented.
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Affiliation(s)
- Jeonghoon Lee
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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60
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61
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Feng X, Liu X, Luo Q, Liu BF. Mass spectrometry in systems biology: an overview. MASS SPECTROMETRY REVIEWS 2008; 27:635-660. [PMID: 18636545 DOI: 10.1002/mas.20182] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
As an emerging field, systems biology is currently the talk of the town, which challenges our philosophy in comprehending biology. Instead of the reduction approach advocated in molecular biology, systems biology aims at systems-level understanding of correlations among molecular components. Such comprehensive investigation requires massive information from the "omics" cascade demanding high-throughput screening techniques. Being one of the most versatile analytical methods, mass spectrometry has already been playing a significant role at this early stage of systems biology. In this review, we documented the advances in modern mass spectrometry technologies as well as nascent inventions. Recent applications of mass spectrometry-based techniques and methodologies in genomics, proteomics, transcriptomics and metabolomics will be further elaborated individually. Undoubtedly, more applications of mass spectrometry in systems biology can be expected in the near future.
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Affiliation(s)
- Xiaojun Feng
- The Key Laboratory of Biomedical Photonics of MOE, Department of Systems Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
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62
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Label-free fluorescence detection in capillary and microchip electrophoresis. Anal Bioanal Chem 2008; 393:515-25. [PMID: 18982318 DOI: 10.1007/s00216-008-2452-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 09/18/2008] [Accepted: 10/01/2008] [Indexed: 12/14/2022]
Abstract
Herein, we summarize the current status of native fluorescence detection in microchannel electrophoresis, with a strong focus on chip-based systems. Fluorescence detection is a powerful technique with unsurpassed sensitivity down to the single-molecule level. Accordingly fluorescence detection is attractive in combination with miniaturised separation techniques. A drawback is, however, the need to derivatize most analytes prior to analysis. This can often be circumvented by utilising excitation light in the UV spectral range in order to excite intrinsic fluorescence. As sensitive absorbance detection is challenging in chip-based systems, deep-UV fluorescence detection is currently one of the most general optical detection techniques in microchip electrophoresis, which is especially attractive for the detection of unlabelled proteins. This review gives an overview of research on native fluorescence detection in capillary (CE) and microchip electrophoresis (MCE) between 1998 and 2008. It discusses material aspects of native fluorescence detection and the instrumentation used, with particular focus on the detector design. Newer developments, featured techniques, and their prospects in the future are also included. In the last section, applications in bioanalysis, drug determination, and environmental analysis are reviewed with regard to limits of detection.
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63
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Winkle RF, Nagy JM, Cass AEG, Sharma S. Towards microfluidic technology-based MALDI-MS platforms for drug discovery: a review. Expert Opin Drug Discov 2008; 3:1281-92. [DOI: 10.1517/17460441.3.11.1281] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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64
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An R, Hoffman MD, Donoghue MA, Hunt AJ, Jacobson SC. Water-assisted femtosecond laser machining of electrospray nozzles on glass microfluidic devices. OPTICS EXPRESS 2008; 16:15206-15211. [PMID: 18795059 DOI: 10.1364/oe.16.015206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Using water-assisted femtosecond laser machining, we fabricated electrospray nozzles on glass coverslips and on assembled microfluidic devices. Machining the nozzles after device assembly facilitated alignment of the nozzles over the microchannels. The basic nozzle design is a through-hole in the coverslip to pass liquids and a trough machined around the through-hole to confine the electrospray and prevent liquid from wicking across the glass surface. Electrospray from the nozzles was stable with and without pressure-driven flow applied and was evaluated using mass spectra of the peptide bradykinin.
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Affiliation(s)
- Ran An
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
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65
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Mellors JS, Gorbounov V, Ramsey RS, Ramsey JM. Fully integrated glass microfluidic device for performing high-efficiency capillary electrophoresis and electrospray ionization mass spectrometry. Anal Chem 2008; 80:6881-7. [PMID: 18698800 PMCID: PMC3125599 DOI: 10.1021/ac800428w] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A microfabricated device has been developed in which electrospray ionization is performed directly from the corner of a rectangular glass microchip. The device allows highly efficient electrokinetically driven separations to be coupled directly to a mass spectrometer (MS) without the use of external pressure sources or the insertion of capillary spray tips. An electrokinetic-based hydraulic pump is integrated on the chip that directs eluting materials to the monolithically integrated spray tip. A positively charged surface coating, PolyE-323, is used to prevent surface interactions with peptides and proteins and to reverse the electroosmotic flow in the separation channel. The device has been used to perform microchip CE-MS analysis of peptides and proteins with efficiencies over 200,000 theoretical plates (1,000,000 plates/m). The sensitivity and stability of the microfabricated ESI source were found to be comparable to that of commercial pulled fused-silica capillary nanospray sources.
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Affiliation(s)
- J. S. Mellors
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapman Hall, Room 251, Chapel Hill, North Carolina 27599-3216
| | - V. Gorbounov
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapman Hall, Room 251, Chapel Hill, North Carolina 27599-3216
| | - R. S. Ramsey
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapman Hall, Room 251, Chapel Hill, North Carolina 27599-3216
| | - J. M. Ramsey
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapman Hall, Room 251, Chapel Hill, North Carolina 27599-3216
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66
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Tomás R, Klepárník K, Foret F. Multidimensional liquid phase separations for mass spectrometry. J Sep Sci 2008; 31:1964-79. [PMID: 18615817 DOI: 10.1002/jssc.200800113] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Large part of the current research in biology, medicine, and biotechnology depends on the analysis of DNA (genomics), proteins (proteomics), or metabolites (metabolomics). The advances in biotechnology also command development of adequate analytical instrumentation capable to analyze minute amounts of samples. The analysis of the content of single cells may serve as an example of ultimate analytical applications. Most of the separation techniques have been developed in the last three decades and alternative approaches are being investigated. At present, the main protocols for analyses of complex mixtures include 2-DE (IEF) followed by electrophoresis in SDS polyacrylamide gel (SDS-PAGE) and chromatographic techniques. Information-rich techniques such as MS and NMR are essential for the identification and structure analysis of the analyzed compounds. High resolution separation of the individual sample components is often a prerequisite for success. High resolution proteomic analysis in the majority of laboratories still relies on the time consuming and laborious offline methods. This review highlights some of the important aspects of 2-D separations including microfluidics.
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Affiliation(s)
- Roman Tomás
- Institute of Analytical Chemistry, Brno, Czech Republic
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67
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Lee J, Musyimi HK, Soper SA, Murray KK. Development of an automated digestion and droplet deposition microfluidic chip for MALDI-TOF MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2008; 19:964-972. [PMID: 18479934 DOI: 10.1016/j.jasms.2008.03.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Revised: 03/26/2008] [Accepted: 03/26/2008] [Indexed: 05/26/2023]
Abstract
An automated proteolytic digestion bioreactor and droplet deposition system was constructed with a plastic microfluidic device for off-line interfacing to matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The microfluidic chips were fabricated in poly(methyl methacrylate) (PMMA), using a micromilling machine and incorporated a bioreactor, which was 100 microm wide, 100 microm deep, and possessed a 4 cm effective channel length (400 nL volume). The chip was operated by pressure-driven flow and mounted on a robotic fraction collector system. The PMMA bioreactor contained surface immobilized trypsin, which was covalently attached to the UV-modified PMMA surface using coupling reagents N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) and hydroxysulfosuccinimide (sulfo-NHS). The digested peptides were mixed with a MALDI matrix on-chip and deposited as discrete spots on MALDI targets. The bioreactor provided efficient digestion of a test protein, cytochrome c, at a flow rate of 1 microL/min, producing a reaction time of approximately 24 s to give adequate sequence coverage for protein identification. Other proteins were also evaluated using this solid-phase bioreactor. The efficiency of digestion was evaluated by monitoring the sequence coverage, which was 64%, 35%, 58%, and 47% for cytochrome c, bovine serum albumin (BSA), myoglobin, and phosphorylase b, respectively.
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Affiliation(s)
- Jeonghoon Lee
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70802, USA
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68
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Freire SLS, Yang H, Wheeler AR. A practical interface for microfluidics and nanoelectrospray mass spectrometry. Electrophoresis 2008; 29:1836-43. [DOI: 10.1002/elps.200700661] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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69
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Mohammed S, Kraiczek K, Pinkse MWH, Lemeer S, Benschop JJ, Heck AJR. Chip-Based Enrichment and NanoLC−MS/MS Analysis of Phosphopeptides from Whole Lysates. J Proteome Res 2008; 7:1565-71. [DOI: 10.1021/pr700635a] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Shabaz Mohammed
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands, and Agilent Technologies R&D and Marketing GmbH & Company KG, Hewlett-Packard-Strasse 8, 76337 Waldbronn, Germany
| | - Karsten Kraiczek
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands, and Agilent Technologies R&D and Marketing GmbH & Company KG, Hewlett-Packard-Strasse 8, 76337 Waldbronn, Germany
| | - Martijn W. H. Pinkse
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands, and Agilent Technologies R&D and Marketing GmbH & Company KG, Hewlett-Packard-Strasse 8, 76337 Waldbronn, Germany
| | - Simone Lemeer
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands, and Agilent Technologies R&D and Marketing GmbH & Company KG, Hewlett-Packard-Strasse 8, 76337 Waldbronn, Germany
| | - Joris J. Benschop
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands, and Agilent Technologies R&D and Marketing GmbH & Company KG, Hewlett-Packard-Strasse 8, 76337 Waldbronn, Germany
| | - Albert J. R. Heck
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands, and Agilent Technologies R&D and Marketing GmbH & Company KG, Hewlett-Packard-Strasse 8, 76337 Waldbronn, Germany
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70
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On the use of different mass spectrometric techniques for characterization of sequence variability in genomic DNA. Anal Bioanal Chem 2008; 391:135-49. [DOI: 10.1007/s00216-008-1929-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 01/25/2008] [Accepted: 01/31/2008] [Indexed: 10/22/2022]
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71
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18 Coupling CE and microchip-based devices with mass spectrometry. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0149-6395(07)00018-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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72
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Sikanen T, Tuomikoski S, Ketola RA, Kostiainen R, Franssila S, Kotiaho T. Fully Microfabricated and Integrated SU-8-Based Capillary Electrophoresis-Electrospray Ionization Microchips for Mass Spectrometry. Anal Chem 2007; 79:9135-44. [DOI: 10.1021/ac071531+] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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73
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Dawoud AA, Sarvaiya HA, Lazar IM. Microfluidic platform with mass spectrometry detection for the analysis of phosphoproteins. Electrophoresis 2007; 28:4645-60. [DOI: 10.1002/elps.200700355] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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74
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Koster S, Verpoorte E. A decade of microfluidic analysis coupled with electrospray mass spectrometry: an overview. LAB ON A CHIP 2007; 7:1394-1412. [PMID: 17960264 DOI: 10.1039/b709706a] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This review presents a thorough overview covering the period 1997-2006 of microfluidic chips coupled to mass spectrometry through an electrospray interface. The different types of fabrication processes and materials used to fabricate these chips throughout this period are discussed. Three 'eras' of interfaces are clearly distinguished. The earliest approach involves spraying from the edge of a chip, while later devices either incorporate a standard fused-silica emitter inserted into the device or fully integrated emitters formed during chip fabrication. A summary of microfluidic-electrospray devices for performing separations and sample pretreatment steps before sample introduction into the mass spectrometer is also presented.
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Affiliation(s)
- Sander Koster
- Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713AV Groningen, The Netherlands.
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75
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Hampton CY, Forbes TP, Varady MJ, Meacham JM, Fedorov AG, Degertekin FL, Fernández FM. Analytical performance of a venturi-assisted array of micromachined ultrasonic electrosprays coupled to ion trap mass spectrometry for the analysis of peptides and proteins. Anal Chem 2007; 79:8154-61. [PMID: 17914864 PMCID: PMC2543123 DOI: 10.1021/ac071297n] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The analytical characterization of a novel ion source for mass spectrometry named array of micromachined ultrasonic electrosprays (AMUSE) is presented here. This is a fundamentally different type of ion generation device, consisting of three major components: (1) a piezoelectric transducer that creates ultrasonic waves at one of the resonant frequencies of the sample-filled device, (2) an array of pyramidally shaped nozzles micromachined on a silicon wafer, and (3) a spacer which prevents contact between the array and transducer ensuring the transfer of acoustic energy to the sample. A high-pressure gradient generated at the apexes of the nozzle pyramids forces the periodic ejection of multiple droplet streams from the device. With this device, the processes of droplet formation and droplet charging are separated; hence, the limitations of conventional electrospray-type ion sources, including the need for high charging potentials and the addition of organic solvent to decrease surface tension, can be avoided. In this work, a Venturi device is coupled with AMUSE in order to increase desolvation, droplet focusing, and signal stability. Results show that ionization of model peptides and small tuning molecules is possible with dc charging potentials of 100 Vdc or less. Ionization in rf-only mode (without dc biasing) was also possible. It was observed that, when combined with AMUSE, the Venturi device provides a 10-fold gain in signal-to-noise ratio for 90% aqueous sample solutions. Further reduction in the diameter of the orifices of the micromachined arrays led to an additional signal gain of at least 3 orders of magnitude, a 2-10-fold gain in the signal-to-noise ratio and an improvement in signal stability from 47% to 8.5% RSD. The effectiveness of this device for the soft ionization of model proteins in aqueous media, such as cytochrome c, was also examined, yielding spectra with an average charge state of 8.8 when analyzed with a 100 Vdc charging potential. Ionization of model proteins was also possible in rf-only mode.
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Affiliation(s)
- Christina Y. Hampton
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Thomas P. Forbes
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Mark J. Varady
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - J. Mark Meacham
- Biochemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, MD 20899
| | - Andrei G. Fedorov
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332
| | - F. Levent Degertekin
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Facundo M. Fernández
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332
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76
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Jo K, Heien ML, Thompson LB, Zhong M, Nuzzo RG, Sweedler JV. Mass spectrometric imaging of peptide release from neuronal cells within microfluidic devices. LAB ON A CHIP 2007; 7:1454-60. [PMID: 17960271 DOI: 10.1039/b706940e] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Microfluidic devices are well suited for manipulating and measuring mass limited samples. Here we adapt a microfluidic device containing functionalized surfaces to chemically stimulate a small number of neurons (down to a single neuron), collect the release of neuropeptides, and characterize them using mass spectrometry. As only a small fraction of the peptides present in a neuron are released with physiologically relevant stimulations, the amount of material available for measurement is small, thereby requiring minimal sample loss and high-sensitivity detection. Although a number of detection schemes are used with microfluidic devices, mass spectrometric detection is used here because of its high information content, allowing the characterization of the released peptide complement. Rather than using an on-line approach, off-line analysis is used; after collection of the peptides onto a surface, mass spectrometric imaging interrogates that surface to determine the peptides released from the cell. The overall utility of this scheme is demonstrated using several device formats with measurement of neuropeptides released from Aplysia californica bag cell neurons.
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Affiliation(s)
- Kyubong Jo
- Department of Chemistry and the Beckman Institute, University of Illinois at Urbana-Champaign, 405 N. Mathew Avenue, Urbana, Illinois 61801, USA
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77
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Höltzel A, Tallarek U. Ionic conductance of nanopores in microscale analysis systems: where microfluidics meets nanofluidics. J Sep Sci 2007; 30:1398-419. [PMID: 17623420 DOI: 10.1002/jssc.200600427] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In this tutorial review we illustrate the origin and dependence on various system parameters of the ionic conductance that exists in discrete nanochannels as well as in nanoporous separation and preconcentration units contained as hybrid configurations, membranes, packed beds, or monoliths in microscale liquid phase analysis systems. A particular complexity arises as external electrical fields are superimposed on internal chemical and electrical potential gradients for tailoring molecular transport. It is demonstrated that the variety of geometries in which the microfluidic/nanofluidic interfaces are realized share common, fundamental features of coupled mass and charge transport, but that phenomena behind the key steps in a particular application can be significantly tuned, depending on the morphology of a material. Thus, the understanding of morphology-related transport in internal and external electrical potential gradients is critical to the performance of a device. This addresses a variety of geometries (slits, channels, filters, membranes, random or regular networks of pores, etc.) and applications, e. g., the gating, sensing, preconcentration, and separation in multifunctional miniaturized devices. Inherently coupled mass and charge transport through ion-permselective (charge-selective) microfluidic/nanofluidic interfaces is analyzed with a stepwise-added complexity and discussed with respect to the morphology of the charge-selective spatial domains. Within this scenario, the electrostatics and electrokinetics in microfluidic and nanofluidic channels, as well as the electrohydrodynamics evolving at microfluidic/nanofluidic interfaces, where microfluidics meets nanofluidics, define the platform of central phenomena.
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Affiliation(s)
- Alexandra Höltzel
- Institut für Verfahrenstechnik, Otto-von-Guericke-Universität, Magdeburg, Germany
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78
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Forbes TP, Degertekin FL, Fedorov AG. Multiplexed operation of a micromachined ultrasonic droplet ejector array. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:104101. [PMID: 17979436 DOI: 10.1063/1.2785156] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A dual-sample ultrasonic droplet ejector array is developed for use as a soft-ionization ion source for multiplexed mass spectrometry (MS). Such a multiplexed ion source aims to reduce MS analysis time for multiple analyte streams, as well as allow for the synchronized ejection of the sample(s) and an internal standard for quantitative results and mass calibration. Multiplexing is achieved at the device level by division of the fluid reservoir and separating the active electrodes of the piezoelectric transducer for isolated application of ultrasonic wave energy to each domain. The transducer is mechanically shaped to further reduce the acoustical crosstalk between the domains. Device design is performed using finite-element analysis simulations and supported by experimental characterization. Isolated ejection of approximately 5 microm diameter water droplets from individual domains in the micromachined droplet ejector array at around 1 MHz frequency is demonstrated by experiments. The proof-of-concept demonstration using a dual-sample device also shows potential for multiplexing with larger numbers of analytes.
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Affiliation(s)
- Thomas P Forbes
- G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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79
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Hardouin J, Joubert-Caron R, Caron M. HPLC-chip-mass spectrometry for protein signature identifications. J Sep Sci 2007; 30:1482-7. [PMID: 17623429 DOI: 10.1002/jssc.200600444] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This work investigates the use of an HPLC-chip microfluidic device interfaced to an IT mass spectrometer to search for biomarker signatures. To that end, the identification of autoantigens is chosen as a model. It not only constitutes a proof of concept model but also the growing interest in autoantibodies and autoantigens as new markers of diseases provides a practical application at the same time. The peptides are separated by the HPLC-chip system allowing suitable resolution and reproducibility. The determination of two parameters that characterize a peptide sequence during LC-MS/MS analyses, retention time (RT) and m/z ratio, improves the identification of a number of peptides derived from protein digests. These findings illustrate that accurate RT measurement obtained in a microfluidic device is useful to obtain mass/retention time (MRT) pairs for a given peptide, which can contribute to the definition of biomarker signatures.
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Affiliation(s)
- Julie Hardouin
- Laboratory of Protein Biochemistry and Proteomics, UMR CNRS 7033, UFR SMBH, Paris13 University, Bobigny, France.
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80
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Smith JC, Lambert JP, Elisma F, Figeys D. Proteomics in 2005/2006: developments, applications and challenges. Anal Chem 2007; 79:4325-43. [PMID: 17477510 DOI: 10.1021/ac070741j] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jeffrey C Smith
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ontario, Canada K1H 8M5
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81
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Zamfir AD. Recent advances in sheathless interfacing of capillary electrophoresis and electrospray ionization mass spectrometry. J Chromatogr A 2007; 1159:2-13. [PMID: 17428492 DOI: 10.1016/j.chroma.2007.03.115] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2006] [Revised: 03/20/2007] [Accepted: 03/29/2007] [Indexed: 01/13/2023]
Abstract
On line sheathless capillary electrophoresis (CE)-electrospray ionization (ESI) mass spectrometry is developing as a powerful method in bioanalytics as it provides high resolution, sensitivity, relatively short analysis times, and amenability to a wide class of compounds. However, unlike the popular nano liquid chromatography (nano LC) or sheath-flow CE/ESI-MS, the sheathless coupling lacks standardized designs and protocols. For this reason, sheathless CE/ESI is a subject of conceptual and technical upgrading more than any other liquid-based separation method hyphenated to MS. Here, recent innovations in sheathless CE/ESI-MS interfacing are gathered in a survey covering the 2005/2006 period. In the first part of the review, the current concepts and methods for in-laboratory production of sturdy designs based on either conductive emitters or electrodeless interfaces are described. The second part is dedicated to microchip CE platforms with externally connected emitters for sheathless coupling to ESI-MS and advanced microfluidic devices integrating CE and sheathless electrospray in a single chip substrate. The advantages, limitations and feasibility for certain applications of all these systems as well as the perspectives for their performance improvement are concurrently assessed.
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Affiliation(s)
- Alina D Zamfir
- Department of Chemistry and Biology, University of Arad, Revolutiei Blvd. 1, RO-310139 Arad, Romania.
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82
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:407-418. [PMID: 17326037 DOI: 10.1002/jms.1072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
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83
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Scriba GKE. Nonaqueous capillary electrophoresis-mass spectrometry. J Chromatogr A 2007; 1159:28-41. [PMID: 17316665 DOI: 10.1016/j.chroma.2007.02.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 01/30/2007] [Accepted: 02/05/2007] [Indexed: 11/27/2022]
Abstract
Nonaqueous background electrolytes broaden the application of capillary electrophoresis displaying altered separation selectivity and interactions between analytes and buffer additives compared to aqueous background electrolytes. In addition, nonaqueous capillary electrophoresis (NACE) appears to be ideally suited for online coupling with mass spectrometry due to the high volatility and low surface tension of many organic solvents. Despite these advantages and an increasing use of nonaqueous background electrolytes in CE, coupling of NACE to mass spectrometry has not yet been applied very often to date. The present review summarizes the applications of online NACE-MS with regard to the analysis of drugs, stereoisomers, peptides, alkaloids, polymers and others. A brief discussion of solvent effects in NACE and pH of nonaqueous background electrolyte systems is also presented.
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Affiliation(s)
- Gerhard K E Scriba
- Friedrich-Schiller-University Jena, School of Pharmacy, Philosophenweg 14, 07743 Jena, Germany.
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84
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Foret F, Kusý P. Microdevices in mass spectrometry. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2007; 13:41-4. [PMID: 17878537 DOI: 10.1255/ejms.834] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Miniaturization of laboratory instrumentation is becoming critical in achieving the speed and throughput required by the current revolutionary progress in biology. This mini review critically summarizes the present status of microfluidic devices designed for use in mass spectrometry.
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Affiliation(s)
- F Foret
- Institute of Analytical Chemistry, Veverí 97, 60200 Brno, Czech Republic
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85
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Benavente F, Vescina MC, Hernández E, Sanz-Nebot V, Barbosa J, Guzman NA. Lowering the concentration limits of detection by on-line solid-phase extraction–capillary electrophoresis–electrospray mass spectrometry. J Chromatogr A 2007; 1140:205-12. [PMID: 17174962 DOI: 10.1016/j.chroma.2006.11.092] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Revised: 11/23/2006] [Accepted: 11/29/2006] [Indexed: 01/22/2023]
Abstract
The use of solid-phase extraction coupled on-line to capillary electrophoresis using electrospray mass spectrometry detection (SPE-CE-ESI-MS) is described for the analysis of peptides in dilute solutions. A SPE microcartridge or analyte concentrator containing C(18) derivatized silica particles as the extraction sorbent was easily constructed near the inlet of the separation capillary using commercially available materials. The reversed-phase sorbent selectively retained the target peptides, enabling large volumes of the sample to be introduced (>100muL). The captured analytes were eluted in a small volume of an appropriate solution (20-50nL). This resulted in sample clean-up and concentration enhancement, with minimum sample handling. As the SPE-CE conditions were compatible with on-line ESI-MS detection, the potential for identifying and characterizing the preconcentrated analytes by SPE-CE-ESI-MS using a sheath-flow CE-ESI-MS interface is also shown. Using separation electrolytes containing N-[carbamoylmethyl]-2-aminoethanesulfonic acid (ACES) at pH 7.4, an elution plug of 80:20 (v/v) (25mM of formic acid in MeCN):H(2)O and a sheath liquid of 20mM of acetic acid in 50:50 (v/v) methanol:H(2)O the concentration limits of detection for the analyzed peptides in the positive ion mode were lowered to nanogram per milliliter levels. The systematic optimization of the operational parameters involved in the development of the SPE-CE method is described in detail, in order to promote robust and quantitative SPE-CE-ESI-MS analysis and facilitate the widespread use of the technique.
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Affiliation(s)
- Fernando Benavente
- Department of Analytical Chemistry, University of Barcelona, Diagonal 647, 08028 Barcelona, Spain.
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86
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Nissilä T, Sainiemi L, Sikanen T, Kotiaho T, Franssila S, Kostiainen R, Ketola RA. Silicon micropillar array electrospray chip for drug and biomolecule analysis. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:3677-3682. [PMID: 17957810 DOI: 10.1002/rcm.3266] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have developed a lidless micropillar array electrospray ionization chip (microPESI) combined with mass spectrometry (MS) for analysis of drugs and biomolecules. The microPESI chip, made of silicon, contains a sample introduction spot for a liquid sample, an array of micropillars (diameter, height, and distance between pillars in the range of 15-200, 20-40, and 2-80 microm, respectively), and a sharpened tip for direct electrospray formation. The microchips were fabricated using deep reactive ion etching (DRIE) which results in accurate dimensional control. The chip, providing a reliable open-channel filling structure based on capillary forces and a electrospray emitter tip for ionization, allows an easy operation and reliable, non-clogging liquid transfer. The microPESI chip can be used for a fast analysis using single sampling or for continuous infusion measurements using a syringe pump for sample introduction. The microPESI-MS shows high sensitivity, with limit of detection 30 pmol/L (60 amol or 28 fg) for verapamil measured with tandem mass spectrometry (MS/MS) and using a sample volume of 2.5 microL. The system shows also good quantitative linearity (r2 > 0.99) with linear dynamic range of at least six orders of magnitude and good ion current stability (standard deviation <5%) in 1-h continuous flow measurement. The microPESI-MS is shown to be a very potential method for direct analysis of drugs and biomolecules.
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Affiliation(s)
- Teemu Nissilä
- Division of Pharmaceutical Chemistry, P.O. Box 56, FI-00014 University of Helsinki, Finland
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87
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Abstract
Recent advances of microfluidics systems suitable for multiplexed MS analysis are reviewed with respect to fabrication technologies and applications.
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88
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Grym J, Otevrel M, Foret F. Aerodynamic mass spectrometry interfacing of microdevices without electrospray tips. LAB ON A CHIP 2006; 6:1306-14. [PMID: 17102844 DOI: 10.1039/b605599k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A new concept for electrospray coupling of microfluidic devices with mass spectrometry was developed. The sampling orifice of the time-of-flight mass spectrometer was modified with an external adapter assisting in formation and transport of the electrosprayed plume from the multichannel polycarbonate microdevice. The compact disk sized microdevice was designed with radial channels extending to the circumference of the disk. The electrospray exit ports were formed by the channel openings on the surface of the disk rim. No additional tips at the channel exits were used. Electrospray was initiated directly from the channel openings by applying high voltage between sample wells and the entrance of the external adapter. The formation of the spatially unstable droplet at the electrospray openings was eliminated by air suction provided by a pump connected to the external adapter. Compared with the air intake through the original mass spectrometer sampling orifice, more than an order of magnitude higher flow rate was achieved for efficient transport of the electrospray plume into the mass spectrometer. Additional experiments with electric potentials applied between the entrance sections of the external adapter and the mass spectrometer indicated that the air flow was the dominant transport mechanism. Basic properties of the system were tested using mathematical modeling and characterized using ESI/TOF-MS measurements of peptide and protein samples.
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Affiliation(s)
- Jakub Grym
- Institute of Analytical Chemistry, Veveri 97, 61142 Brno, Czech Republic
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89
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Hardouin J, Duchateau M, Joubert-Caron R, Caron M. Usefulness of an integrated microfluidic device (HPLC-Chip-MS) to enhance confidence in protein identification by proteomics. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:3236-44. [PMID: 17016832 DOI: 10.1002/rcm.2725] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Nanoflow liquid chromatography/mass spectrometry (nanoLC/MS) has become a current tool in proteomics applications increasingly used in the search for new biomarkers. A new integrated microfluidic device (HPLC-Chip), coupled to ion trap mass spectrometry (ITMS), appears as an innovative and robust tool for improving the identifications commonly performed by nanoLC/MS/MS. We tested this device for the identification of proteins obtained from two-dimensional gel electrophoresis or chromatography. The chip allows the measurement of reproducible retention times that, in association with m/z ratios, was found useful for identifying peptide sequences without ambiguity. A sensitivity increase of a factor of at least 5-fold is obtained compared to the results obtained previously in our laboratory by conventional nanoLC/MS/MS on the same ion trap. We conclude that this recently available microfluidic device can be a valuable tool during biomarker discovery programs, particularly identifying low-abundance proteins.
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Affiliation(s)
- Julie Hardouin
- Laboratory of Protein Biochemistry and Proteomics, UMR CNRS 7033 (BioMoCeTi), UFR SMBH, Paris13 University, 93017 Bobigny cedex, France.
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