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Hiraoka K, Sakai Y, Kubota H, Ninomiya S, Rankin-Turner S. An Investigation of the Non-selective Etching of Synthetic Polymers by Electrospray Droplet Impact/Secondary Ion Mass Spectrometry (EDI/SIMS). Mass Spectrom (Tokyo) 2022; 12:A0114. [DOI: 10.5702/massspectrometry.a0114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Affiliation(s)
- Kenzo Hiraoka
- Clean Energy Research Center, University of Yamanashi
| | - Yuji Sakai
- Clean Energy Research Center, University of Yamanashi
| | | | | | - Stephanie Rankin-Turner
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University
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2
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Schneider P, Verloh F, Portz A, Aoyagi S, Rohnke M, Dürr M. Direct Analysis of Ion-Induced Peptide Fragmentation in Secondary-Ion Mass Spectrometry. Anal Chem 2020; 92:15604-15610. [PMID: 33170642 DOI: 10.1021/acs.analchem.0c03765] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Primary-ion-induced fragmentation in organic molecules can strongly influence the results in secondary-ion mass spectrometry (SIMS) of organic and biomolecular samples. In order to characterize this ion-induced fragmentation, oligopeptide samples irradiated in SIMS experiments were investigated by means of desorption/ionization induced by neutral SO2 clusters (DINeC). The latter is a nondestructive desorption method for mass spectrometry of biomolecules, which gives direct access to the fragments induced in the sample. Comparison of TOF-SIMS and DINeC mass spectra revealed qualitative differences between the fragments, which remain in the sample and the fragments sputtered during ion bombardment. The fragmentation strength and its spatial distribution were found to be quantitatively different for Bi1+, Bi3+, and Ar1000+ primary ions, leading to different distributions of the degree of fragmentation in the samples as directly measured by means of DINeC depth profiles.
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Affiliation(s)
- P Schneider
- Institut für Angewandte Physik and Zentrum für Materialforschung, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
| | - F Verloh
- Institut für Angewandte Physik and Zentrum für Materialforschung, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany.,Physikalisch-Chemisches Institut and Zentrum für Materialforschung, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
| | - A Portz
- Institut für Angewandte Physik and Zentrum für Materialforschung, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
| | - S Aoyagi
- Department of Materials and Life Science, Seikei University, 3-3-1, Kichijyoji-kitamachi, Musashino-shi, Tokyo 180-8633, Japan
| | - M Rohnke
- Physikalisch-Chemisches Institut and Zentrum für Materialforschung, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
| | - M Dürr
- Institut für Angewandte Physik and Zentrum für Materialforschung, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
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Delcorte A, Delmez V, Dupont-Gillain C, Lauzin C, Jefford H, Chundak M, Poleunis C, Moshkunov K. Large cluster ions: soft local probes and tools for organic and bio surfaces. Phys Chem Chem Phys 2020; 22:17427-17447. [PMID: 32568320 DOI: 10.1039/d0cp02398a] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Ionised cluster beams have been produced and employed for thin film deposition and surface processing for half a century. In the last two decades, kiloelectronvolt cluster ions have also proved to be outstanding for surface characterisation by secondary ion mass spectrometry (SIMS), because their sputter and ion yields are enhanced in a non-linear fashion with respect to monoatomic projectiles, with a resulting step change of sensitivity for analysis and imaging. In particular, large gas cluster ion beams, or GCIB, have now become a reference in organic surface and thin film analysis using SIMS and X-ray photoelectron spectroscopy (XPS). The reason is that they induce soft molecular desorption and offer the opportunity to conduct damageless depth-profiling and 3D molecular imaging of the most sensitive organic electronics and biological samples, with a nanoscale depth resolution. In line with these recent developments, the present review focuses on rather weakly-bound, light-element cluster ions, such as noble or other gas clusters, and water or alcohol nanodroplets (excluding clusters made of metals, inorganic salts or ionic liquids) and their interaction with surfaces (essentially, but not exclusively, organic). The scope of this article encompasses three aspects. The first one is the fundamentals of large cluster impacts with surfaces, using the wealth of information provided by molecular dynamics simulations and experimental observations. The second focus is on recent applications of large cluster ion beams in surface characterisation, including mass spectrometric analysis and 2D localisation of large molecules, molecular depth-profiling and 3D molecular imaging. Finally, the perspective explores cutting edge developments, involving (i) new types of clusters with a chemistry designed to enhance performance for mass spectrometry imaging, (ii) the use of cluster fragment ion backscattering to locally retrieve physical surface properties and (iii) the fabrication of new biosurface and thin film architectures, where large cluster ion beams are used as tools to transfer biomolecules in vacuo from a target reservoir to any collector substrate.
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Affiliation(s)
- Arnaud Delcorte
- Université Catholique de Louvain, Institute of Condensed Matter and Nanoscience, 1 Place Louis Pasteur, 1348 Louvain-la-Neuve, Belgium.
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4
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Fast Atom Bombardment. Mass Spectrom (Tokyo) 2017. [DOI: 10.1007/978-3-319-54398-7_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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5
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Fujiwara Y, Saito N. Effects of a proton-conducting ionic liquid on secondary ion formation in time-of-flight secondary ion mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:239-249. [PMID: 26661991 DOI: 10.1002/rcm.7439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 10/16/2015] [Accepted: 10/25/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE A protic ionic liquid, diethylmethylammonium trifluoromethanesulfonate ([dema][TfO]), has low vapor pressure and high protonic conductivity even at room temperature. Since [dema][TfO] has a mobile proton in its salt structure, its primary beam is expected to enhance the formation of protonated molecular ions. However, mass spectrometric characteristics of [dema][TfO] are not well known. In order to develop an ionic-liquid primary beam source, it is necessary to investigate such characteristics. METHODS The first time-of-flight secondary ion mass spectrometry (TOF-SIMS) experiment using an Ar(+) primary ion beam was performed to analyze two samples: a neat [dema][TfO] sample and a mixed sample of arginine and [dema][TfO]. Beam characteristics of [dema][TfO] generated by vacuum electrospray were investigated using an apparatus for measuring transient responses of a beam current. The second TOF-SIMS experiment using a [dema][TfO] primary beam was performed to analyze three samples: arginine, a mixture of arginine and [dema][TfO], and poly(ethylene glycol) (PEG300). RESULTS The [dema][TfO] primary beam was useful in generating protonated arginine; however, it was not helpful in detecting PEG300. The results were explained by considering gas-phase basicities and proton affinities of analytes and [dema][TfO] constituents. Projectile energy per nucleon of the [dema][TfO] beam was examined; it would be necessary to reduce m/z values of ionic-liquid charged droplets. In addition, a screening method was proposed to select ionic liquids suitable for primary ion beams. CONCLUSIONS Since [dema][TfO] can act as a proton source, its primary beam can effectively generate protonated secondary ions of analytes. Consequently, proton-conducting ionic liquids such as [dema][TfO] are expected to have great potentials as primary ion beams in TOF-SIMS.
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Affiliation(s)
- Yukio Fujiwara
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2, 1-1-1 Umezono, Tsukuba-shi, Ibaraki-ken, 305-8568, Japan
| | - Naoaki Saito
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2, 1-1-1 Umezono, Tsukuba-shi, Ibaraki-ken, 305-8568, Japan
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6
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Zhang J, Franzreb K, Aksyonov SA, Williams P. Mass Spectra and Yields of Intact Charged Biomolecules Ejected by Massive Cluster Impact for Bioimaging in a Time-of-Flight Secondary Ion Microscope. Anal Chem 2015; 87:10779-84. [PMID: 26452076 DOI: 10.1021/acs.analchem.5b01802] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Impacts of massive, highly charged glycerol clusters (≳10(6) Da, ≳ ± 100 charges) have been used to eject intact charged molecules of peptides, lipids, and small proteins from pure solid samples, enabling imaging using these ion species in a time-of-flight secondary ion microscope with few-micrometer spatial resolution. Here, we report mass spectra and useful ion yields (ratio of intact charged molecules detected to molecules sputtered) for several molecular species-two peptides, bradykinin and angiotensin II; two lipids, phosphatidylcholine and sphingomyelin; Irganox 1010 (a detergent); insulin; and rhodamine B-and show that useful ion yields are high enough to enable bioimaging of peptides and lipids in biological samples with few-micrometer resolution and acceptable signals. For example, several hundred molecular ion counts should be detectable from a 3 × 3 μm(2) area of a pure lipid bilayer given appropriate instrumentation or tens of counts from a minor constituent of such a layer.
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Affiliation(s)
- Jitao Zhang
- Department of Chemistry & Biochemistry, Arizona State University , PO Box 1604, Tempe, Arizona 85287-1604, United States
| | - Klaus Franzreb
- Department of Chemistry & Biochemistry, Arizona State University , PO Box 1604, Tempe, Arizona 85287-1604, United States
| | - Sergei A Aksyonov
- Department of Chemistry & Biochemistry, Arizona State University , PO Box 1604, Tempe, Arizona 85287-1604, United States
| | - Peter Williams
- Department of Chemistry & Biochemistry, Arizona State University , PO Box 1604, Tempe, Arizona 85287-1604, United States
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Takaishi R, Sakai Y, Hiraoka K, Wada H, Morita S, Nakashima T, Nonami H. Electrospray droplet impact secondary ion mass spectrometry using a vacuum electrospray source. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:1420-1426. [PMID: 26147482 DOI: 10.1002/rcm.7240] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 05/29/2015] [Accepted: 05/30/2015] [Indexed: 06/04/2023]
Abstract
RATIONALE In electrospray droplet impact (EDI) developed in our laboratory, an atmospheric pressure electrospray source has been used. To increase the ion beam intensity and reduce the evacuation load, a vacuum electrospray cluster ion source using a silica capillary was developed. METHODS A silica capillary with a tip inner diameter of 8 µm was used for vacuum electrospray using aqueous 10% methanol. To stabilize the flow rate of the liquid for nano-electrospray, a home-made constant pressure liquid pump was also developed. RESULTS By using the silica tip nano-electrospray emitter and a constant pressure pump, stable electrospray with flow rate of 22 nL/min was realized without using any heating system such as laser irradiation. Comparative study of mass spectra obtained by atmospheric pressure EDI (A-EDI) and vacuum EDI (V-EDI) was made for various samples such as thermometer molecule, peptide, polystyrene, Alq(3), NPD, C(60), indium, and SiO(2). V-EDI showed slightly milder ionization than A-EDI. CONCLUSIONS Because V-EDI gave higher target current (5-10 nA) than A-EDI (a few nA at most), V-EDI secondary ion mass spectrometry (SIMS) would be a useful technique for the surface and interface analysis.
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Affiliation(s)
- R Takaishi
- Clean Energy Research Center, University of Yamanashi, Takeda-4, Kofu, 400-8511, Japan
| | - Y Sakai
- Clean Energy Research Center, University of Yamanashi, Takeda-4, Kofu, 400-8511, Japan
| | - K Hiraoka
- Clean Energy Research Center, University of Yamanashi, Takeda-4, Kofu, 400-8511, Japan
| | - H Wada
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization (NARO), 496 Izumi, Fukuoka, 833-0041, Japan
| | - S Morita
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization (NARO), 496 Izumi, Fukuoka, 833-0041, Japan
| | - T Nakashima
- Plant Biophysics/Biochemistry Research Laboratory, Faculty of Agriculture, Ehime University, Matsuyama, 790-8566, Japan
| | - H Nonami
- Plant Biophysics/Biochemistry Research Laboratory, Faculty of Agriculture, Ehime University, Matsuyama, 790-8566, Japan
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8
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Electrospray droplet impact/secondary ion mass spectrometry (EDI/SIMS) using NaF and AgF as cationization matrices. SURF INTERFACE ANAL 2015. [DOI: 10.1002/sia.5782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Zhang J, Franzreb K, Williams P. Imaging with biomolecular ions generated by massive cluster impact in a time-of-flight secondary ion microscope. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:2211-2216. [PMID: 25178725 DOI: 10.1002/rcm.7006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 07/28/2014] [Accepted: 07/29/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Imaging mass spectrometry can allow the correlation of molecular identification and spatial organization in biological samples. A useful technique would rapidly generate, from untreated samples, images of lipids, peptides and small proteins with intracellular spatial resolution. We describe the use of massive, highly charged glycerol cluster impact to produce images using ionized, intact biomolecules, with few-micrometer lateral resolution and few-minute acquisition times. METHODS An electrospray primary ion source generating massive clusters of electrolyte-doped glycerol was coupled with a microscope-imaging time-of-flight secondary ion mass spectrometer. A continuous stream of primary cluster ions ejected secondary ions from the sample surface. The secondary ion stream was pulsed in the secondary column and either time-of-flight mass spectra or mass-selected ion images were projected onto a position-sensitive ion detector. The image acquisition times were a few minutes. RESULTS Ionized intact molecules of some common lipids, peptides and small proteins have been detected. A lateral image resolution of ~3 µm has been measured for a bradykinin ion image. CONCLUSIONS Massive cluster impact (MCI) combined with microscope-mode ion imaging allows rapid imaging using ionized intact biomolecules, with a lateral resolution acceptable for applications with biological samples.
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Affiliation(s)
- Jitao Zhang
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ, 85287-1604, USA
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Fujiwara Y, Saito N. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) using an ionic-liquid primary ion beam source. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5662] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yukio Fujiwara
- National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Central 2, 1-1-1 Umezono Tsukuba-shi Ibaraki-ken 305-8568 Japan
| | - Naoaki Saito
- National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Central 2, 1-1-1 Umezono Tsukuba-shi Ibaraki-ken 305-8568 Japan
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Takaishi R, Hiraoka K. Electrospray droplet impact/secondary ion mass spectrometry (EDI/SIMS) using mixed solvents of water/methanol and water/2-propanol as projectile droplets. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5531] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Rio Takaishi
- University of Yamanashi; Clean Energy Reserch Center; 4-3-11 Takeda Kofu Yamanashi 400-8511 Japan
| | - Kenzo Hiraoka
- University of Yamanashi; Clean Energy Reserch Center; 4-3-11 Takeda Kofu Yamanashi 400-8511 Japan
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Takaishi R, Hiraoka K. Electrospray droplet impact/secondary ion mass spectrometry (EDI/SIMS) for silver halides. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5360] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rio Takaishi
- Clean Energy Research Center; University of Yamanashi; Takeda-4 Kofu 400-8511 Japan
| | - Kenzo Hiraoka
- Clean Energy Research Center; University of Yamanashi; Takeda-4 Kofu 400-8511 Japan
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Hiraoka K, Asakawa D, Takaishi R. Estimation of useful yields for electrospray droplet impact/secondary ion mass spectrometry (EDI/SIMS). SURF INTERFACE ANAL 2012. [DOI: 10.1002/sia.5191] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Kenzo Hiraoka
- Clean Energy Research Center; University of Yamanashi; Kofu; 400-8511; Japan
| | - Daiki Asakawa
- Clean Energy Research Center; University of Yamanashi; Kofu; 400-8511; Japan
| | - Rio Takaishi
- Clean Energy Research Center; University of Yamanashi; Kofu; 400-8511; Japan
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Fujiwara Y, Saito N, Nonaka H, Ichimura S. Emission characteristics of a charged-droplet beam source using vacuum electrospray of an ionic liquid. SURF INTERFACE ANAL 2012. [DOI: 10.1002/sia.5071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Yukio Fujiwara
- National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Central 2, 1-1-1 Umezono; Tsukuba-shi; Ibaraki-ken; 305-8568; Japan
| | - Naoaki Saito
- National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Central 2, 1-1-1 Umezono; Tsukuba-shi; Ibaraki-ken; 305-8568; Japan
| | - Hidehiko Nonaka
- National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Central 2, 1-1-1 Umezono; Tsukuba-shi; Ibaraki-ken; 305-8568; Japan
| | - Shingo Ichimura
- National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Central 2, 1-1-1 Umezono; Tsukuba-shi; Ibaraki-ken; 305-8568; Japan
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15
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Asakawa D, Hiraoka K. Surface characterization and depth profiling of biological molecules by electrospray droplet impact/SIMS. SURF INTERFACE ANAL 2011. [DOI: 10.1002/sia.3821] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Daiki Asakawa
- Graduate School in Nanobioscience; Yokohama City University, 22-2 Seto; Kanazawa-ku; Yokohama; 236-0027; Japan
| | - Kenzo Hiraoka
- Clean Energy Research Center; The University of Yamanashi, Takeda 4-3-11; Kofu; 400-8511; Japan
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Fast Atom Bombardment. Mass Spectrom (Tokyo) 2011. [DOI: 10.1007/978-3-642-10711-5_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Gebhardt C, Tomsic A, Schröder H, Dürr M, Kompa K. Matrix-Free Formation of Gas-Phase Biomolecular Ions by Soft Cluster-Induced Desorption. Angew Chem Int Ed Engl 2009; 48:4162-5. [DOI: 10.1002/anie.200804431] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Gebhardt C, Tomsic A, Schröder H, Dürr M, Kompa K. Matrix-Free Formation of Gas-Phase Biomolecular Ions by Soft Cluster-Induced Desorption. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200804431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Garrison BJ, Postawa Z. Computational view of surface based organic mass spectrometry. MASS SPECTROMETRY REVIEWS 2008; 27:289-315. [PMID: 18421766 DOI: 10.1002/mas.20165] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Surface based mass spectrometric approaches fill an important niche in the mass analysis portfolio of tools. The particular niche depends on both the underlying physics and chemistry of molecule ejection as well as experimental characteristics. In this article, we use molecular dynamics computer simulations to elucidate the fundamental processes giving rise to ejection of organic molecules in atomic and cluster secondary ion mass spectrometry (SIMS), massive cluster impact (MCI) mass spectrometry, and matrix-assisted laser desorption ionization (MALDI) mass spectrometry. This review is aimed at graduate students and experimental researchers.
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Affiliation(s)
- Barbara J Garrison
- Department of Chemistry, Penn State University, 104 Chemistry Building, University Park, Pennsylvania 16802, USA.
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MORI K, HIRAOKA K. Internal Energy Transfer to Secondary Ions in Electrospray Droplet Impact/Secondary Ion Mass Spectrometry. ACTA ACUST UNITED AC 2008. [DOI: 10.5702/massspec.56.33] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
Imaging mass spectrometry combines the chemical specificity and parallel detection of mass spectrometry with microscopic imaging capabilities. The ability to simultaneously obtain images from all analytes detected, from atomic to macromolecular ions, allows the analyst to probe the chemical organization of a sample and to correlate this with physical features. The sensitivity of the ionization step, sample preparation, the spatial resolution, and the speed of the technique are all important parameters that affect the type of information obtained. Recently, significant progress has been made in each of these steps for both secondary ion mass spectrometry (SIMS) and matrix-assisted laser desorption/ionization (MALDI) imaging of biological samples. Examples demonstrating localization of proteins in tumors, a reduction of lamellar phospholipids in the region binding two single celled organisms, and sub-cellular distributions of several biomolecules have all contributed to an increasing upsurge in interest in imaging mass spectrometry. Here we review many of the instrumental developments and methodological approaches responsible for this increased interest, compare and contrast the information provided by SIMS and MALDI imaging, and discuss future possibilities.
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Affiliation(s)
- Liam A McDonnell
- FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands
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Asakawa D, Fujimaki S, Hashimoto Y, Mori K, Hiraoka K. Study on ion formation in electrospray droplet impact secondary ion mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:1579-86. [PMID: 17428014 DOI: 10.1002/rcm.3004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A new type of cluster secondary ion mass spectrometry (SIMS), named electrospray droplet impact (EDI), has been developed in our laboratory. In general, rather strong negative ions as well as positive ions can be generated by EDI compared with conventional SIMS. In this work, various aspects of ion formation in EDI are investigated. The Brønsted bases (proton acceptor) and acids (proton donor) mixed in the analyte samples enhanced the signal intensities of deprotonated molecules (negative ions) and protonated molecules (positive ions), respectively, for analytes. This suggests the occurrence of heterogeneous proton transfer reactions (i.e. M + M' --> [M+H](+) + [M'-H](-)) in the shockwave-heated selvedge of the colliding interface between the water droplet and the solid sample deposited on the metal substrate. EDI-SIMS shows a remarkable tolerance to the large excess of salts present in samples. The mechanism for desorption/ionization in EDI is much simpler than those for MALDI and SIMS because only very thin sample layers take part in the shockwave-heated selvedge and complicated higher-order reactions are largely suppressed.
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Affiliation(s)
- Daiki Asakawa
- Clean Energy Research Center, University of Yamanashi, Kofu, Japan
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Venter A, Sojka PE, Cooks RG. Droplet Dynamics and Ionization Mechanisms in Desorption Electrospray Ionization Mass Spectrometry. Anal Chem 2006; 78:8549-55. [PMID: 17165852 DOI: 10.1021/ac0615807] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A droplet pickup and other mechanisms have been suggested for the ionization of biomolecules like peptides and proteins by desorption electrospray ionization. To verify this hypothesis phase Doppler particle analysis was used to study the sizes and velocities of droplets involved in DESI. It was found that impacting droplets typically have velocities of 120 m/s and average diameters of 2-4 microm. Small differences in sprayer construction influence the operating conditions at which droplets of these dimensions are produced. Under these conditions, the kinetic energy per impacting water molecule is less than 0.6 meV and sputtering through momentum transfer during collisions or ionization by other electronic processes is unlikely. Droplets arrive at the surface with velocities well below the speed of sound in common materials, thereby excluding the possibility of ionization by shockwave formation. Some droplets appear to roll along the surface, increasing contact time and presumably the amount of material that is taken up into droplets during conditions typical of the DESI experiment.
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Affiliation(s)
- Andre Venter
- Chemistry Department, Purdue University, West Lafayette, Indiana 47907, USA
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Hiraoka K, Mori K, Asakawa D. Fundamental aspects of electrospray droplet impact/SIMS. JOURNAL OF MASS SPECTROMETRY : JMS 2006; 41:894-902. [PMID: 16770831 DOI: 10.1002/jms.1048] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
A new ionization method, electrospray droplet impact ionization (EDI), has been developed for matrix-free secondary-ion mass spectrometry (SIMS). The charged droplets formed by electrospraying 1 M acetic acid aqueous solution are sampled through an orifice with a diameter of 400 microm into the first vacuum chamber, transported into a quadrupole ion guide, and accelerated by 10 kV after exiting the ion guide. The droplets impact on a dry solid sample (no matrix used) deposited on a stainless steel substrate. The secondary ions formed by the impact are transported to a second quadrupole ion guide and mass-analyzed by an orthogonal time-of-flight mass spectrometer (TOF-MS). Ten pmol of gramicidin S could be detected with the presence of as much as 10 nmol of NaCl. The ion signal for arginine disappeared with decrease in the substrate temperature below 150 K owing to the formation of ice film over the sample surface. While 10 fmol of gramicidin S could be detected for 30 min, the ionization/desorption efficiency for EDI becomes smaller with an increase in the molecular weight (MW) of a biological sample. The largest protein samples detected to date are cytochrome c and lysozyme. The high sensitivity for EDI is due to the fact that samples only a few monolayers thick are subject to desorption/ionization by EDI, with little fragmentation. A coherent phonon excitation may be the main mechanism for the desorption/ionization of the solid sample.
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Affiliation(s)
- Kenzo Hiraoka
- Clean Energy Research Center, University of Yamanashi, Takeda-4, Kofu 400-8510, Japan.
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Mori K, Asakawa D, Sunner J, Hiraoka K. Electrospray droplet impact/secondary ion mass spectrometry: cluster ion formation. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:2596-602. [PMID: 16878342 DOI: 10.1002/rcm.2633] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The electrospray droplets that are sampled through an orifice into the vacuum chamber are accelerated by 10 kV and impact on the stainless steel substrate. The mass and the kinetic energy of electrospray droplets are roughly estimated to be a few 10(6) u and approximately 10(6) eV, respectively. The molecular ion M(+.) and the protonated molecule [M+H](+) are observed as secondary ions for chrysene and coronene deposited on the metal substrate (no matrix used). The ionization may take place in the shock wave generated by the high-momentum coherent collision between the droplet projectile and the solid sample. Cluster ions of H(+)(H(2)O)(n) and CF(3)COO(-)(H(2)O)(n), with n up to approximately 150, were observed as secondary ions formed by the electrospray droplet impact ionization (EDI) for 10(-2) M trifluoroacetic acid (TFA) aqueous solution. This indicates that the charged droplets that collide with the metal substrate with the kinetic energy of approximately 10(6) eV do not vaporize completely but are disintegrated into many tiny microdroplets. The ion signal intensity anomalies (i.e. magic numbers) were observed for the cluster ions of H(3)O(+)(H(2)O)(n) and CF(3)COO(-)(H(2)O)(n) for 10(-2) M TFA aqueous solution and of Cs(+)(H(2)O)(n), I(-)(H(2)O)(n), Cs(+)(CsI)(n), and I(-)(CsI)(n) for 10(-2) M CsI aqueous solution.
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Affiliation(s)
- Kunihiko Mori
- Clean Energy Research Center, University of Yamanashi, Takeda-4, Kofu 400-8511, Japan
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Furuya H, Fujimaki S, Kambara S, Suzuki S, Hashimoto Y, Okazaki S, Wada A, Beech IB, Sunner J, Hiraoka K. Ion/molecule reactions in the orifice-skimmer region of an atmospheric pressure Penning ionization mass spectrometer. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:2433-42. [PMID: 16059883 DOI: 10.1002/rcm.2085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Atmospheric pressure Penning ionization mass spectra of methanol were measured as functions of Ar or He gas pressure in the first vacuum chamber, the position of the skimmer, and the voltage applied between the orifice and the skimmer. When the orifice and the skimmer were coaxial with a distance of 4 mm, the distribution of CH3OH2+(CH3OH)n clusters was only weakly dependent on both Ar pressure (in the range of 19-220 Pa) and orifice-skimmer voltage (in the range of 1-45 V). The ion/molecule reaction CH3OH2+ + CH3OH --> CH3+(CH3OH) + H2O was observed in the free jet expansion, especially at high orifice-skimmer voltage values. When the orifice and the skimmer were off-centered and the distance between them was increased to 18 mm, the formation of large CH3OH2+(CH3OH)n clusters, as well as their dissociation, were seen. The endothermic proton transfer reaction, CH3+(CH3OH) + CH3OH --> CH3OH2+ + CH3OCH3, occurred at high orifice-skimmer voltage. The collision-induced dissociation of cluster ions by He gas in the first vacuum chamber was much more efficient than by Ar. These results demonstrated that the mass spectra are highly dependent on skimmer position and on orifice-skimmer voltage and that ions observed by mass spectrometry do not necessarily reflect the abundance of ions produced in the atmospheric pressure ion source.
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Affiliation(s)
- Hiroko Furuya
- Clean Energy Research Center, University of Yamanashi, Takeda-4, Kofu 400-8511, Japan
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Delcorte A, Garrison BJ. Kiloelectronvolt Argon-Induced Molecular Desorption from a Bulk Polystyrene Solid. J Phys Chem B 2004. [DOI: 10.1021/jp0402131] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Fast Atom Bombardment. Mass Spectrom (Tokyo) 2004. [DOI: 10.1007/3-540-36756-x_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Aksyonov SA, Williams P. Impact desolvation of electrosprayed microdroplets--a new ionization method for mass spectrometry of large biomolecules. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:2001-2006. [PMID: 11675666 DOI: 10.1002/rcm.470] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Impact desolvation of electrosprayed microdroplets (IDEM) is a new method for producing gas-phase ions of large biomolecules. Analytes are dissolved in an electrolyte solution which is electrosprayed in vacuum, producing highly charged micron and sub-micron sized droplets (microdroplets). These microdroplets are accelerated through potential differences approximately 5 - 10 kV to velocities of several km/s and allowed to impact a target surface. The energetic impacts vaporize the droplets and release desolvated gas-phase ions of the analyte molecules. Oligonucleotides (2- to 12-mer) and peptides (bradykinin, neurotensin) yield singly and doubly charged molecular ions with no detectable fragmentation. Because the extent of multiple charging is significantly less than in atmospheric pressure electrospray ionization, and the method produces ions largely free of adducts from solutions of high ionic strength, IDEM has some promise as a method for coupling to liquid chromatographic techniques and for mixture analysis. Ions are produced in vacuum at a flat equipotential surface, potentially allowing efficient ion extraction.
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Affiliation(s)
- S A Aksyonov
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-1604, USA
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Delcorte A, Garrison BJ. High Yield Events of Molecular Emission Induced by Kiloelectronvolt Particle Bombardment. J Phys Chem B 2000. [DOI: 10.1021/jp001374h] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wittmaack K, Szymczak W, Hoheisel G, Tuszynski W. Time-of-flight secondary ion mass spectrometry of matrix-diluted oligo- and polypeptides bombarded with slow and fast projectiles: positive and negative matrix and analyte ion yields, background signals, and sample aging. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2000; 11:553-563. [PMID: 10833029 DOI: 10.1016/s1044-0305(00)00110-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Human angiotensin II, chain B of bovine insulin, and porcine insulin were determined by time-of-flight secondary ion mass spectrometry under impact of approximately 25 keV Xe+ and SF5+ ion beams and approximately 100 MeV 252Cf fission fragments. Matrix-embedded samples, dissolved in a large surplus of alpha-cyano-4-hydroxycinnamic acid, were prepared by nebulizer spray deposition, neat samples by the droplet technique. It is shown that the status of the sample can be assessed by evaluating the matrix-specific features of the mass spectra. The beneficial effect of matrix isolation was small for angiotensin but large for the insulin samples, which did not show parent peaks from neat material. Negative ion yields under SF5+ impact were up to a factor of 50 higher than with Xe+. For positive secondary ions, the enhancement was much smaller. The mass spectra produced by slow ion beams or fast fission fragments were qualitatively similar. Quantitative differences include the following: with fast projectiles the yields were about 10-30 times higher than with slow ions, but similar for negative ion emission under SF5+ bombardment; the analyte-to-matrix yield ratios were higher with slow ions and up to 250 times higher than the molar analyte concentration; for analyte ions the peak-to-background ratios were higher using slow projectiles; the fraction of carbon-rich collisionally formed molecular ions was much higher with fast projectiles. Sample aging in vacuum for up to five weeks strongly reduced the yield of protonated analyte molecules ejected by slow ion impact, but not of deprotonated species. Hence protonation seems to correlate with sample "wetness" or the presence of volatile proton-donating additives.
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Affiliation(s)
- K Wittmaack
- GSF-National Research Center for Environment and Health, Institute of Radiation Protection, Neuherberg, Germany.
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Cheng HP. Cluster-surface collisions: Characteristics of Xe55- and C20–Si[111] surface bombardment. J Chem Phys 1999. [DOI: 10.1063/1.480085] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Qi L, Sinnott SB. Polymerization via Cluster−Solid Surface Impacts: Molecular Dynamics Simulations. J Phys Chem B 1997. [DOI: 10.1021/jp971340i] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lifeng Qi
- Department of Chemical and Materials Engineering, The University of Kentucky, Lexington, Kentucky, 40506-0046
| | - Susan B. Sinnott
- Department of Chemical and Materials Engineering, The University of Kentucky, Lexington, Kentucky, 40506-0046
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Abstract
Ion/ion proton transfer reactions are shown to be an effective means to facilitate the resolution of ions in electrospray mass spectrometry that differ in mass and charge but are similar in mass-to-charge ratio. Examples are shown in which a minor contaminant protein in a ribonuclease B solution is clearly apparent after ion/ion proton transfer but not in the conventional electrospray mass spectrum. A further example involving a mixture of bovine serum albumin and bovine transferrin also showed the identification of previously unnoticed "contaminant" polymer. The latter mixture also illustrated important issues in the use of the quadrupole ion trap as a reaction vessel and mass analyzer for high mass-to-charge ratio ions. The results suggest that the use of ion trap operating parameters specifically tailored for storage, ejection, detection, and mass-to-charge analysis of high mass-to-charge ratio ions can have attractive analytical figures of merit for determining mixtures of relatively high-mass proteins and, by extension, other types of high-mass biopolymers.
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Affiliation(s)
- J L Stephenson
- Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, Tennessee 37831-6365, USA
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Herron WJ, Goeringer DE, McLuckey SA. Product ion charge state determination via ion/ion proton transfer reactions. Anal Chem 1996; 68:257-62. [PMID: 9027235 DOI: 10.1021/ac950895b] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Proton transfer from protonated pyridine to product anions derived from quadrupole ion trap collisional activation of the triply charged anion of the oligonucleotide 5'-d(AAAA)-3' and the 6- charge state of oxidized bovine insulin A-chain is shown to be a rapid and effective way to determine product charge states. The reactions are carried out in a quadrupole ion trap as part of a procedure involving three stages of mass analysis. It is demonstrated that the reactions can be driven at rates sufficiently high to convert 30-80% of the initial product anion population to second generation products in 50-200 ms. The use of ion/ion reactions enjoys significant advantages over the use of ion/molecule proton transfer chemistry. For example, ion/ion reactions are more universal than ion/molecule reactions due to their greater exothermicity, and ion/ion reactions allow for precise control over the timing of introduction and ejection of each reactant. Despite the high exothermicity of the reactions, no significant fragmentation of product ions derived from high-mass multiply charged anions is observed.
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Affiliation(s)
- W J Herron
- Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, Tennessee 37831-6365, USA
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Stephenson JL, McLuckey SA. Ion/Ion Reactions in the Gas Phase: Proton Transfer Reactions Involving Multiply-Charged Proteins. J Am Chem Soc 1996. [DOI: 10.1021/ja9611755] [Citation(s) in RCA: 169] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hendell E, Even U. Cluster–surface interaction at high kinetic energy. I. Electron emission. J Chem Phys 1995. [DOI: 10.1063/1.470015] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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McMahon JM, Dookeran NN, Todd PJ. Organic ion imaging beyond the limit of static secondary ion mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 1995; 6:1047-58. [PMID: 24214051 DOI: 10.1016/1044-0305(95)00526-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/1995] [Revised: 06/16/1995] [Accepted: 06/20/1995] [Indexed: 05/22/2023]
Abstract
Secondary ion mass spectra and images were obtained from spikes of choline chloride, acetylcholine chloride, and methylphenylpyridinium iodide deposited onto specimens of porcine brain tissue. Samples were subsequently subjected to a dose of 10-keV Cs(+) sufficient to suppress secondary ion emission characteristic of the targeted analytes. Following ablation of the samples by massive glycerol clusters generated by electrohydrodynamic emission, secondary ion mass spectra and images could be obtained that reflected the identity and location of the spiked analytes. The absolute intensity of secondary ion emission that followed ablation was found to be between 30 and 100% of the intensity obtained prior to exposure to the high dose of Cs'. Not all chemical noise is removed by ablation, however, so that the signal-to-noise ratios after ablation correspond to between 10 and 85% of their values observed under conditions of low primary ion dose.
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Affiliation(s)
- J M McMahon
- Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
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Cornett DS, Lee TD, Mahoney JF. Matrix-free desorption of biomolecules using massive cluster impact. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1994; 8:996-1000. [PMID: 7696706 DOI: 10.1002/rcm.1290081218] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Massive-cluster impact (MCI) ionization was found to be capable of producing high secondary-ion yields from biological samples without the use of a liquid matrix. Dry samples of molecules as large as cytochrome c were observed to be efficiently desorbed without significant fragmentation by the MCI beam of glycerol clusters. In addition, signals from protonated molecules retained a significant proportion of their initial intensity even after several minutes exposure to the primary beam. It was determined that these remarkable phenomena are not the result of the build-up of a layer of glycerol caused by the cluster bombardment.
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Affiliation(s)
- D S Cornett
- Division of Immunology, Beckman Research Institute of the City of Hope, Duarte, California 91010
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Schek I, Raz T, Levine RD, Jortner J. Cluster impact chemistry. High‐energy collisions of I2ArN clusters with a Pt surface. J Chem Phys 1994. [DOI: 10.1063/1.468055] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mahoney JF, Cornett DS, Lee TD. Formation of multiply charged ions from large molecules using massive-cluster impact. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1994; 8:403-406. [PMID: 8025336 DOI: 10.1002/rcm.1290080513] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Massive-cluster impact is demonstrated to be an effective ionization technique for the mass analysis of proteins as large as 17 kDa. The design of the cluster source permits coupling to both magnetic-sector and quadrupole mass spectrometers. Mass spectra are characterized by the almost total absence of chemical background and a predominance of multiply charged ions formed from 100% glycerol matrix. The number of charge states produced by the technique is observed to range from +3 to +9 for chicken egg lysozyme (14,310 Da). The lower m/z values provided by higher charge states increase the effective mass range of analyses performed with conventional ionization by fast-atom bombardment or liquid secondary ion mass spectrometry.
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Affiliation(s)
- J F Mahoney
- Phrasor Scientific Inc., Duarte, California 91010
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