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Cooper-Shepherd DA, Wildgoose J, Kozlov B, Johnson WJ, Tyldesley-Worster R, Palmer ME, Hoyes JB, McCullagh M, Jones E, Tonge R, Marsden-Edwards E, Nixon P, Verenchikov A, Langridge JI. Novel Hybrid Quadrupole-Multireflecting Time-of-Flight Mass Spectrometry System. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:264-272. [PMID: 36603847 PMCID: PMC9896552 DOI: 10.1021/jasms.2c00281] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/05/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
A novel mass spectrometry system is described here comprising a quadrupole-multireflecting time-of-flight design. The new multireflecting time-of-flight analyzer has an effective path length of 48 m and employs planar, gridless ion mirrors providing fourth-order energy focusing resulting in resolving power over 200 000 fwhm and sub-ppm mass accuracy. We show how these attributes are maintained with relatively fast acquisition speeds, setting the system apart from other high resolution mass spectrometers. We have integrated this new system into both liquid chromatography-mass spectrometry and mass spectrometry imaging workflows to demonstrate how the instrument characteristics are of benefit to these applications.
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Affiliation(s)
| | - Jason Wildgoose
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - Boris Kozlov
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - William J. Johnson
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | | | - Martin E. Palmer
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - John B. Hoyes
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - Michael McCullagh
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - Emrys Jones
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - Robert Tonge
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - Emma Marsden-Edwards
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | - Peter Nixon
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
| | | | - James I. Langridge
- Waters
Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, Cheshire, U.K.SK9 4AX
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Bajo KI, Aoki J, Ishihara M, Furuya S, Nishimura M, Yoshitake M, Yurimoto H. Development of electrostatic-induced charge detector for multiturn time-of-flight mass spectrometer. JOURNAL OF MASS SPECTROMETRY : JMS 2022; 57:e4892. [PMID: 36376098 DOI: 10.1002/jms.4892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/03/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
We developed an autocorrelation function to resolve the overtaking problem in a multiturn time-of-flight mass spectrometer (TOF-MS). The function analyzes the characteristic period for one lap of each ion packet and derives a mass spectrum from a signal pulse train composed of multiturn ion packets. To detect the ion pulse train, a new nondestructive ion detector was developed and installed in the multiturn orbit of MULTUM-S II. This detector is composed of an electrostatically induced charge detector, a preamplifier, and a digitizer. The electrostatic noises are smaller than the single-ion signals owing to the accumulation of the multiturn TOF spectrum. The conventional ion detector of TOF-MS is operated after collecting the signal pulse train. The multiturn TOF spectrum was convolved with an autocorrelation function to derive the mass spectrum. The convolved mass spectrum performed a mass resolving power (MRP) of 28,200 at m/z 69 and mass accuracy of 28 ppm for the perfluorotributylamine (PFTBA) gas sample.
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Affiliation(s)
- Ken-Ichi Bajo
- Department of Earth and Planetary Sciences, Hokkaido University, Sapporo, Japan
| | - Jun Aoki
- Department of Physics, Graduate School of Science, Osaka University, Toyonaka, Japan
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
- Riken Center for Biosystems Dynamics Research, Kobe, Japan
| | - Morio Ishihara
- Department of Physics, Graduate School of Science, Osaka University, Toyonaka, Japan
| | | | | | | | - Hisayoshi Yurimoto
- Department of Earth and Planetary Sciences, Hokkaido University, Sapporo, Japan
- ISAS/JAXA, Sagamihara, Japan
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Murphy DM. The sTOF, a Favorable Geometry for a Time-of-Flight Analyzer. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:242-246. [PMID: 27830526 DOI: 10.1007/s13361-016-1518-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 09/25/2016] [Accepted: 09/27/2016] [Indexed: 06/06/2023]
Abstract
A new geometry for the flight region in a time-of-flight mass spectrometer is presented. It consists of two opposing electrostatic sectors of about 255° each and straight sections with a length appropriate to the turns. The resulting geometry folds into a compact space. The first-order aberrations for position, angle, and energy are all zero. The transverse focusing properties are also excellent. For an energetic, high-divergence ion source such as laser ablation, the sTOF has higher resolution and ion transmission than a reflectron of similar physical size. Graphical Abstract ᅟ.
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Affiliation(s)
- Daniel M Murphy
- Chemical Sciences Division, National Oceanic and Atmospheric Administration, Earth System Research Laboratory, 325 Broadway, Boulder, CO, 80305, USA.
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Halford E, Winter B, Mills MD, Thompson SP, Parr V, John JJ, Nomerotski A, Vallance C, Turchetta R, Brouard M. Modifications to a commercially available linear mass spectrometer for mass-resolved microscopy with the pixel imaging mass spectrometry (PImMS) camera. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:1649-1657. [PMID: 24975244 DOI: 10.1002/rcm.6940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 03/27/2014] [Accepted: 05/02/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Imaging mass spectrometry is a powerful analytical technique capable of accessing a large volume of spatially resolved, chemical data from two-dimensional samples. Probing the entire surface of a sample simultaneously requires a detector with high spatial and temporal resolutions, and the ability to observe events relating to different mass-to-charge ratios. METHODS A commercially available time-of-flight mass spectrometer, designed for matrix-assisted laser desorption/ionization (MALDI) analysis, was combined with the novel pixel imaging mass spectrometry (PImMS) camera in order to perform multi-mass, microscope-mode imaging experiments. A number of minor modifications were made to the spectrometer hardware and ion optics so that spatial imaging was achieved for a number of small molecules. RESULTS It was shown that a peak width of Δm50 % < 1 m/z unit across the range 200 ≤ m/z ≤ 800 can be obtained while also achieving an optimum spatial resolution of 25 µm. It was further shown that these data were obtained simultaneously for all analytes present without the need to scan the experimental parameters. CONCLUSIONS This work demonstrates the capability of multi-mass, microscope-mode imaging to reduce the acquisition time of spatially distributed analytes such as multi-arrays or biological tissue sections. It also shows that such an instrument can be commissioned by effecting relatively minor modifications to a conventional commercial machine.
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Affiliation(s)
- E Halford
- The Department of Chemistry, University of Oxford, The Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford, OX1 3QZ, UK
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Satoh T, Kubo A, Hazama H, Awazu K, Toyoda M. Separation of Isobaric Compounds Using a Spiral Orbit Type Time-of-Flight Mass Spectrometer, MALDI-SpiralTOF. Mass Spectrom (Tokyo) 2014; 3:S0027. [PMID: 26819897 DOI: 10.5702/massspectrometry.s0027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 12/10/2013] [Indexed: 11/23/2022] Open
Abstract
The development of a MALDI-TOF mass spectrometer that utilizes spiral ion trajectory, SpiralTOF, is reported. The total flight path length was 17 m, which is five times longer than that in commonly used reflectron ion optical system. The SpiralTOF reduced the dependence of the mass resolving power on the mass of the analyte, while improving the accuracy of the mass measurements. Furthermore, SpiralTOF has two advantages that can be exploited for the separation of minor abundant isobaric components in mass spectra. One is the reduction in chemical background due to the post source decay (PSD), which is achieved through PSD ion elimination by electrostatic sectors contained within the SpiralTOF. The other is that the stabilities of peak positions are improved during mass spectrum accumulation. The peak drift caused by the fine structure of matrix crystals and the small irregularities on the sample surface can be reduced by extending the flight path. In this study, these advantages are demonstrated via the analysis of a block copolymer and mass spectrometry imaging (MSI) of lipids.
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Affiliation(s)
| | | | - Hisanao Hazama
- Medical Beam Physics Lab., School of Engineering, Osaka University
| | - Kunio Awazu
- Medical Beam Physics Lab., School of Engineering, Osaka University
| | - Michisato Toyoda
- Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University
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Satoh T, Kubo A, Shimma S, Toyoda M. Mass Spectrometry Imaging and Structural Analysis of Lipids Directly on Tissue Specimens by Using a Spiral Orbit Type Tandem Time-of-Flight Mass Spectrometer, SpiralTOF-TOF. Mass Spectrom (Tokyo) 2012; 1:A0013. [PMID: 24349914 DOI: 10.5702/massspectrometry.a0013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 10/23/2012] [Indexed: 01/12/2023] Open
Abstract
In this paper, we report the use of mass spectrometry imaging and structural analysis of lipids directly on a tissue specimen, carried out by means of matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry, using a combination of spiral orbit-type and reflectron-type time-of-flight mass spectrometers. The most intense peak observed in the mass spectrum from a brain tissue specimen was confirmed as phosphatidylcholine (34 : 1) [M+K](+), using tandem mass spectrometry. The charge remote fragmentation channels, which are characteristically observed using high-energy collision-induced dissociation, contributed significantly to this confirmation. Accurate mass analysis was further facilitated by mass correction using the confirmed peak. In mass spectrometry imaging, the high resolving power of our system could separate doublet peak of less than 0.1 u difference, which would otherwise be problematic when using a low-resolution reflectron type time-of-flight mass spectrometer. Two compounds, observed at m/z 848.56 and 848.65, were found to be located in complementary positions on a brain tissue specimen. These results demonstrate the importance of a high-performance tandem time-of-flight mass spectrometer for mass spectrometry imaging and analysis of observed compounds, to allow distinction between biological molecules.
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Affiliation(s)
| | | | - Shuichi Shimma
- Division of Integrative Omics and Bioinformatics, National Cancer Center Research Institute
| | - Michisato Toyoda
- Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University
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Shimma S, Miki S, Toyoda M. Polychlorinated biphenyls (PCBs) analysis using a miniaturized high-resolution time-of-flight mass spectrometer “MULTUM-S II”. ACTA ACUST UNITED AC 2012; 14:1664-70. [DOI: 10.1039/c2em30112a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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SATO T, TERAMOTO K, SATOH T, UEDA Y. Ethylene Oxide-Propylene Oxide block Copolymer Analysis by MALDI Spiral-TOF/TOF. KOBUNSHI RONBUNSHU 2012. [DOI: 10.1295/koron.69.406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Toyoda M. Development of multi-turn time-of-flight mass spectrometers and their applications. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2010; 16:397-406. [PMID: 20530824 DOI: 10.1255/ejms.1076] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The mass resolution of a time-of-flight (ToF) mass spectrometer is directly proportional to its total flight path length. We have developed multi-turn ToF mass spectrometers, where ions are stored in a fixed orbit within electrostatic sectors and allowed to propagate the said orbit numerous times. With each successive orbit, the flight path is correspondingly increasing. The first multi-turn ToF mass spectrometer, the MULTUM Linear plus, was developed for cometary exploration. The spectrometer consists of four cylindrical electrostatic sectors and 28 electrostatic quadrupole lenses. The size of the analyzer is 40 cm square. Mass resolution is demonstrated to increase according to the number of ion cycles. A mass resolution of greater than 350,000 was achieved after 501.5 cycles. Another multi-turn ToF mass spectrometer, the MULTUM II, which consists of only four toroidal electrostatic sectors, was also developed in an effort to reduce the number of quadrupole lenses. We are developing various types of mass spectrometer based on the MULTUM II technology, a ToF/ToF mass spectrometer "MULTUM- TOF/TOF", a stigmatic imaging mass spectrometer "MULTUM-IMG" and miniature mass spectrometers of high mass resolving power, the "MULTUM-S" series.
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Affiliation(s)
- Michisato Toyoda
- Department of Physics, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
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Nishiguchi M, Ueno Y, Toyoda M, Setou M. Design of a new multi-turn ion optical system 'IRIS' for a time-of-flight mass spectrometer. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:594-604. [PMID: 19034931 DOI: 10.1002/jms.1531] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A new multi-turn ion optical system 'IRIS' has been designed for use with a high-performance time-of-flight (TOF) mass spectrometer, which satisfies the new design concepts of time focusing and phase space stability. It has an elliptical flight path composed of four toroidal electric sectors, with a flight path length for one lap of 0.974 m. Dimensions and voltages of sector electrodes have been optimized to satisfy theoretical requirements by simulations using surface charge method. Generally, multi-turn instruments require an injection and ejection system to inject and eject ions. On the basis of this ion optical study, we have designed an injection and ejection ion optical system, which achieves time focusing for the total system. Furthermore, we have designed novel field-adjusting electrodes (FAEs) for the perforated sectors in the injection and ejection systems, which accurately correct the electric potential around the perforated sector's hole. We have also used simulations to evaluate mass resolving power and ion transmissions for various lap numbers or flight path lengths. Through these we have confirmed that mass resolving powers of over 100,000 can be achieved with reasonable ion transmissions for a given set of initial conditions. Usually a multi-turn TOF mass spectrometer with a closed optic axis has mass range limitations from overtaking ions. To solve this problem, a TOF segmentation method is proposed that identifies all peaks in a TOF spectrum, including those from overtaking ions.
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Affiliation(s)
- Masaru Nishiguchi
- Production/Design Technology Center, Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto 604-8511, Japan.
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Shimma S, Nagao H, Giannakopulos AE, Hayakawa S, Awazu K, Toyoda M. High-energy collision-induced dissociation of phosphopeptides using a multi-turn tandem time-of-flight mass spectrometer 'MULTUM-TOF/TOF'. JOURNAL OF MASS SPECTROMETRY : JMS 2008; 43:535-537. [PMID: 18069747 DOI: 10.1002/jms.1352] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
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Toyoda M, Giannakopulos AE, Colburn AW, Derrick PJ. High-energy collision induced dissociation fragmentation pathways of peptides, probed using a multiturn tandem time-of-flight mass spectrometer "MULTUM-TOF/TOF". THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:074101. [PMID: 17672775 DOI: 10.1063/1.2751403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A new multiturn tandem time-of-flight (TOF) mass spectrometer "MULTUM-TOF/TOF" has been designed and constructed. It consists of a matrix-assisted laser desorption/ionization ion source, a multiturn TOF mass spectrometer, a collision cell, and a quadratic-field ion mirror. The multiturn TOF mass spectrometer can overcome the problem of precursor ion selection in TOF, due to insufficient time separation between two adjacent TOF peaks, by increasing the number of cycles. As a result, the total TOF increases with the increase in resolving power. The quadratic-field ion mirror allows temporal focusing for fragment ions with different kinetic energies. Product ion spectra from monoisotopically selected precursor ions of angiotensin I, substance P, and bradykinin have been obtained. The fragment ions observed are mainly the result of high-energy collision induced dissociation.
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Affiliation(s)
- Michisato Toyoda
- Department of Physics, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
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SHIMMA S, NAGAO H, TOYODA M. Charge-Remote Fragmentation of Phospholipids in a Multi-Turn Tandem Time-of-Flight Mass Spectrometer"MULTUM-TOF/TOF". ACTA ACUST UNITED AC 2007. [DOI: 10.5702/massspec.55.343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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TOYODA M, NISHIGUCHI M. Simulation of Beam Profile of Multi-Turn Time-of-Flight Mass Spectrometers. ACTA ACUST UNITED AC 2007. [DOI: 10.5702/massspec.55.17] [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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ICHIHARA T, UCHIDA S, ISHIHARA M, KATAKUSE I, TOYODA M. Construction of a Palmtop Size Multi-Turn Time-of-Flight Mass Spectrometer "MULTUM-S". ACTA ACUST UNITED AC 2007. [DOI: 10.5702/massspec.55.363] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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SATOH T, TSUNO H, IWANAGA M, KAMMEI Y. A New Spiral Time-of-Flight Mass Spectrometer for High Mass Analysis. ACTA ACUST UNITED AC 2006. [DOI: 10.5702/massspec.54.11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Satoh T, Tsuno H, Iwanaga M, Kammei Y. The design and characteristic features of a new time-of-flight mass spectrometer with a spiral ion trajectory. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2005; 16:1969-75. [PMID: 16246577 DOI: 10.1016/j.jasms.2005.08.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Revised: 08/15/2005] [Accepted: 08/16/2005] [Indexed: 05/05/2023]
Abstract
A new time-of-flight (TOF) mass spectrometer with a corkscrew ion trajectory was designed and constructed. The spiral trajectory was realized by using four toroidal electrostatic sectors. Each had fifteen-stories made of sixteen Matsuda plates piled up inside a cylindrical electrostatic sector. The ions passed the four toroidal electrostatic sectors sequentially and revolved along a figure-eight-shaped orbit on a certain projection plane. During the multiple revolutions, each ion trajectory was shifted by 50 mm per cycle on a direction perpendicular to the projection plane, thus generating a spiral trajectory. The flight path length of one cycle was 1.308 m so that the maximum flight path length became approximately 20 m. The mass resolution, mass accuracy, and ion transmission were tested by utilizing an orthogonally coupled electron ionization source. A mass resolution of 35,000 (FWHM) for m/z greater than 300 was achieved. Even in a lower mass region, mass resolutions of more than 20,000 (FWHM) were confirmed with a doublet of (12)C(5)(1)H(5)(14)N(+) and (13)C(12)C(5)(1)H(6)(+). The mass accuracy was also improved such that it was better than 1 ppm with only one internal standard peak. An ion transmission of approximately of 100% was observed for 15 cycles.
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Toyoda M, Okumura D, Ishihara M, Katakuse I. Multi-turn time-of-flight mass spectrometers with electrostatic sectors. JOURNAL OF MASS SPECTROMETRY : JMS 2003; 38:1125-1142. [PMID: 14648820 DOI: 10.1002/jms.546] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The mass resolution of a time-of-flight (TOF) mass spectrometer is directly proportional to its total flight pathlength. Multi-turn or multi-passage ion optical geometries are necessary to obtain fight distances of sufficient length within reasonable size limitations. We have investigated ion optics for a multi-turn TOF mass spectrometer with electrostatic sectors. The concept of 'perfect' focusing conditions is introduced. Furthermore, a new type of multi-turn TOF mass spectrometer, the MULTUM Linear plus, was developed. It consists of four cylindrical electric sectors and 28 electric quadrupole lenses. It has a vacuum chamber 60 x 70 x 20 cm in size. Mass resolution is demonstrated to increase according to the number of ion cycles. A mass resolution of 350 000 (m/z = 28, FWHM) was achieved after 501.5 cycles. The MULTUM Linear plus analyzer is not simple, however; 28 electric quadrupole lenses are used. In order to reduce the number of ion optical parts, an improved multi-turn TOF mass spectrometer, the MULTUM II, consisting of only four toroidal electric sectors, was also developed. The possibility of tandem mass spectrometric applications using multi-turn TOF mass spectrometers is also discussed.
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Affiliation(s)
- Michisato Toyoda
- Department of Physics, Graduate School of Science, Osaka University, 1-16 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
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