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Sample records for ion mass spectrometer

  1. Mini ion trap mass spectrometer

    DOEpatents

    Dietrich, D.D.; Keville, R.F.

    1995-09-19

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  2. Mini ion trap mass spectrometer

    DOEpatents

    Dietrich, Daniel D.; Keville, Robert F.

    1995-01-01

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  3. The Giotto ion mass spectrometer

    NASA Technical Reports Server (NTRS)

    Balsiger, H.; Altwegg, K.; Buehler, F.; Fischer, J.; Geiss, J.; Meier, A.; Rettenmund, U.; Rosenbauer, H.; Schwenn, R.; Neugebauer, M.

    1986-01-01

    The Giotto Ion Mass Spectrometer (IMS) consists of two sensors: one optimized for the outer and the other for the inner coma, with each obtaining complementary information in the region for which it is not optimized. The outer coma is characterized by the interaction between solar wind and comentary plasmas, the inner coma by the outflow of cometary neutrals and their ionization products. Both sensors feature mass imaging characteristics, permitting simultaneous measurements of several ion species by multidetector arrays. Resultant mass-per-charge resolution is greater than or = 20. Energy per charge, and the elevation and aximuth of incident ions are measured. Calibration and in-flight solar-wind data show that the IMS will meet its scientific goals for the Halley encounter.

  4. Microscale ion trap mass spectrometer

    DOEpatents

    Ramsey, J. Michael; Witten, William B.; Kornienko, Oleg

    2002-01-01

    An ion trap for mass spectrometric chemical analysis of ions is delineated. The ion trap includes a central electrode having an aperture; a pair of insulators, each having an aperture; a pair of end cap electrodes, each having an aperture; a first electronic signal source coupled to the central electrode; a second electronic signal source coupled to the end cap electrodes. The central electrode, insulators, and end cap electrodes are united in a sandwich construction where their respective apertures are coaxially aligned and symmetric about an axis to form a partially enclosed cavity having an effective radius r.sub.0 and an effective length 2z.sub.0, wherein r.sub.0 and/or z.sub.0 are less than 1.0 mm, and a ratio z.sub.0 /r.sub.0 is greater than 0.83.

  5. The ion mass spectrometer on Giotto

    NASA Technical Reports Server (NTRS)

    Balsiger, H.; Altwegg, K.; Buehler, F.; Fischer, J.; Geiss, J.; Benson, J.; Hemmerich, P.; Goldstein, B. E.; Goldstein, R.; Neugebauer, M.

    1987-01-01

    The design of the Giotto ion mass spectrometer (IMS) system, its calibration, and the initial flight performance are discussed. The IMS system consists of two sensors: one optimized for the outer coma, the other for the inner coma, with each sensor obtaining complementary information in the region for which it was not optimized. Both sensors feature mass-imaging characteristics, permitting simultaneous measurements of several ion species by means of multi-detector arrays, with resultant mass per charge resolution of not less than 20. In addition to mass per charge, the energy per charge and the elevation and azimuth of the incident ions were measured during the Giotto flight.

  6. Ion mobility spectrometer / mass spectrometer (IMS-MS).

    SciTech Connect

    Hunka Deborah Elaine; Austin, Daniel E.

    2005-07-01

    The use of Ion Mobility Spectrometry (IMS) in the Detection of Contraband Sandia researchers use ion mobility spectrometers for trace chemical detection and analysis in a variety of projects and applications. Products developed in recent years based on IMS-technology include explosives detection personnel portals, the Material Area Access (MAA) checkpoint of the future, an explosives detection vehicle portal, hand-held detection systems such as the Hound and Hound II (all 6400), micro-IMS sensors (1700), ordnance detection (2500), and Fourier Transform IMS technology (8700). The emphasis to date has been on explosives detection, but the detection of chemical agents has also been pursued (8100 and 6400). Combining Ion Mobility Spectrometry (IMS) with Mass Spectrometry (MS) is described. The IMS-MS combination overcomes several limitations present in simple IMS systems. Ion mobility alone is insufficient to identify an unknown chemical agent. Collision cross section, upon which mobility is based, is not sufficiently unique or predictable a priori to be able to make a confident peak assignment unless the compounds present are already identified. Molecular mass, on the other hand, is much more readily interpreted and related to compounds. For a given compound, the molecular mass can be determined using a pocket calculator (or in one's head) while a reasonable value of the cross-section might require hours of computation time. Thus a mass spectrum provides chemical specificity and identity not accessible in the mobility spectrum alone. In addition, several advanced mass spectrometric methods, such as tandem MS, have been extensively developed for the purpose of molecular identification. With an appropriate mass spectrometer connected to an ion mobility spectrometer, these advanced identification methods become available, providing greater characterization capability.

  7. Ion Mobility Spectrometer / Mass Spectrometer (IMS-MS).

    SciTech Connect

    Hunka, Deborah E; Austin, Daniel

    2005-10-01

    The use of Ion Mobility Spectrometry (IMS)in the Detection of Contraband Sandia researchers use ion mobility spectrometers for trace chemical detection and analysis in a variety of projects and applications. Products developed in recent years based on IMS-technology include explosives detection personnel portals, the Material Area Access (MAA) checkpoint of the future, an explosives detection vehicle portal, hand-held detection systems such as the Hound and Hound II (all 6400), micro-IMS sensors (1700), ordnance detection (2500), and Fourier Transform IMS technology (8700). The emphasis to date has been on explosives detection, but the detection of chemical agents has also been pursued (8100 and 6400).Combining Ion Mobility Spectrometry (IMS) with Mass Spectrometry (MS)The IMS-MS combination overcomes several limitations present in simple IMS systems. Ion mobility alone is insufficient to identify an unknown chemical agent. Collision cross section, upon which mobility is based, is not sufficiently unique or predictable a priori to be able to make a confident peak assignment unless the compounds present are already identified. Molecular mass, on the other hand, is much more readily interpreted and related to compounds. For a given compound, the molecular mass can be determined using a pocket calculator (or in one's head) while a reasonable value of the cross-section might require hours of computation time. Thus a mass spectrum provides chemical specificity and identity not accessible in the mobility spectrum alone. In addition, several advanced mass spectrometric methods, such as tandem MS, have been extensively developed for the purpose of molecular identification. With an appropriate mass spectrometer connected to an ion mobility spectrometer, these advanced identification methods become available, providing greater characterization capability.3 AcronymsIMSion mobility spectrometryMAAMaterial Access AreaMSmass spectrometryoaTOForthogonal acceleration time

  8. AFE ion mass spectrometer design study

    NASA Technical Reports Server (NTRS)

    Wright, Willie

    1989-01-01

    This final technical report covers the activities engaged in by the University of Texas at Dallas, Center for Space Sciences in conjunction with the NASA Langley Research Center, Systems Engineering Division in design studies directed towards defining a suitable ion mass spectrometer to determine the plasma parameter around the Aeroassisted Flight Experiment vehicle during passage through the earth's upper atmosphere. Additional studies relate to the use of a Langmuir probe to measure windward ion/electron concentrations and temperatures. Selected instrument inlet subsystems were tested in the NASA Ames Arc-Jet Facility.

  9. Proton Transfer Reaction Ion Trap Mass Spectrometer

    SciTech Connect

    Prazeller, Peter; Palmer, Peter T.; Boscaini, Elena; Jobson, B Tom T.; Alexander, M. Lizabeth

    2003-06-11

    Proton transfer reaction mass spectrometry is a relatively new field that has attracted a great deal of interest in the last few years. This technique uses H₃Oþ as a chemical ionization (CI) reagent to measure volatile organic compounds (VOCs) in the parts per billion by volume (ppbv) to parts per trillion by volume (pptv) range. Mass spectra acquired with a proton transfer reaction mass spectrometer (PTR-MS) are simple because proton transfer chemical ionization is ‘soft’ and results in little or no fragmentation. Unfortunately, peak identification can still be difficult due to isobaric interferences. A possible solution to this problem is to couple the PTR drift tube to an ion trap mass spectrometer (ITMS). The use of an ITMS is appealing because of its ability to perform MS/MS and possibly distinguish between isomers and other isobars. Additionally, the ITMS duty cycle is much higher than that of a linear quadrupole so faster data acquisition rates are possible that will allow for detection of multiple compounds. Here we present the first results from a proton transfer reaction ion trap mass spectrometer (PTR-ITMS). The aim of this study was to investigate ion injection and storage efficiency of a simple prototype instrument in order to estimate possible detection limits of a second-generation instrument. Using this prototype a detection limit of 100 ppbv was demonstrated. Modifications are suggested that will enable further reduction in detection limits to the low-ppbv to high-pptv range. Furthermore, the applicability of MS/MS in differentiating between isobaric species was determined. MS/MS spectra of the isobaric compounds methyl vinyl ketone (MVK) and methacrolein (MACR) are presented and show fragments of different mass making differentiation possible, even when a mixture of both species is present in the same sample. However, MS/MS spectra of acetone and propanal produce fragments with the same molecular masses but with different intensity ratios

  10. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2016-11-15

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  11. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  12. Proton Transfer Reaction Ion Trap Mass Spectrometer

    SciTech Connect

    Prazeller, Peter; Palmer, Peter T.; Boscaini, Elena; Jobson, B Tom; Alexander, M. Lizabeth

    2003-07-07

    Proton Transfer Reaction Mass Spectrometry (PTR-MS) is a relatively new field that has attracted a great deal of interest in the last several years. This technique uses H3O+ as a chemical ionization (CI) agent for measuring volatile organic compounds (VOCs) in the parts per billion by volume (ppbv) - parts per trillion by volume (pptv) range. PTR-MS mass spectra are simple because the ionization method of proton transfer is “soft”, resulting in little or no fragmentation. Unfortunately, the simplicity of the mass spectra can cause problems in peak identification due to isobaric interferences. A possible solution to this problem is to couple the PTR drift tube to an ion trap mass spectrometer (ITMS). ITMS is appealing because of the ability to perform MS/MS and possibly distinguish between isomers and other isobars. Additionally, the ITMS duty cycle is much higher than that of a linear quadrupole so faster data acquisition rates can be realized for detection of multiple compounds. We present here the first results from a Proton Transfer Reaction Ion Trap Mass Spectrometer (PTR-ITMS). The aim of this study was to investigate ion injection and storage efficiency of a simple prototype interface in order to estimate possible detection limits of a second generation instrument. Using this prototype a detection limit of 100 ppbv was demonstrated for the PTR-ITMS. Modifications are suggested that will enable further reduction in detection limits to the low ppbv to pptv range. Furthermore the applicability of MS/MS to differentiate between isobaric species was determined. MS/MS spectra of the isobaric compounds methyl vinyl ketone (MVK) and methacrolein (MACR) are presented and show fragments of different mass making a differentiation possible even when a mixture of both species is present in the same sample. MS/MS spectra of acetone and propanal produce fragments with the same molecular weight but different ratios, allowing quantitative distinction only if one species

  13. THOR Ion Mass Spectrometer instrument - IMS

    NASA Astrophysics Data System (ADS)

    Retinò, Alessandro; Kucharek, Harald; Saito, Yoshifumi; Fraenz, Markus; Verdeil, Christophe; Leblanc, Frederic; Techer, Jean-Denis; Jeandet, Alexis; Macri, John; Gaidos, John; Granoff, Mark; Yokota, Shoichiro; Fontaine, Dominique; Berthomier, Matthieu; Delcourt, Dominique; Kistler, Lynn; Galvin, Antoniette; Kasahara, Satoshi; Kronberg, Elena

    2016-04-01

    Turbulence Heating ObserveR (THOR) is the first mission ever flown in space dedicated to plasma turbulence. Specifically, THOR will study how turbulent fluctuations at kinetic scales heat and accelerate particles in different turbulent environments within the near-Earth space. To achieve this goal, THOR payload is being designed to measure electromagnetic fields and particle distribution functions with unprecedented resolution and accuracy. Here we present the Ion Mass Spectrometer (IMS) instrument that will measure the full three-dimensional distribution functions of near-Earth main ion species (H+, He+, He++ and O+) at high time resolution (~ 150 ms for H+ , ~ 300 ms for He++) with energy resolution down to ~ 10% in the range 10 eV/q to 30 keV/q and angular resolution ~ 10°. Such high time resolution is achieved by mounting multiple sensors around the spacecraft body, in similar fashion to the MMS/FPI instrument. Each sensor combines a top-hat electrostatic analyzer with deflectors at the entrance together with a time-of-flight section to perform mass selection. IMS electronics includes a fast sweeping high voltage board that is required to make measurements at high cadence. Ion detection includes Micro Channel Plates (MCP) combined with Application-Specific Integrated Circuits (ASICs) for charge amplification, discrimination and time-to-digital conversion (TDC). IMS is being designed to address many of THOR science requirements, in particular ion heating and acceleration by turbulent fluctuations in foreshock, shock and magnetosheath regions. The IMS instrument is being designed and will be built by an international consortium of scientific institutes with main hardware contributions from France, USA, Japan and Germany.

  14. Ion Neutral Mass Spectrometer Measurements from Titan

    NASA Technical Reports Server (NTRS)

    Waite, J. H., Jr.; Niemann, H.; Yelle, R. V.; Kasprzak, W.; Cravens, T.; Luhmann, J.; McNutt, R.; Ip, W.-H.; Gell, D.; Muller-Wordag, I. C. F.

    2005-01-01

    Introduction: The Ion Neutral Mass Spectrometer (INMS) aboard the Cassini orbiter has obtained the first in situ composition measurements of the neutral densities of molecular nitrogen, methane, argon, and a host of stable carbon-nitrile compounds in its first flyby of Titan. The bulk composition and thermal structure of the moon s upper atmosphere do not appear to be changed since the Voyager flyby in 1979. However, the more sensitive techniques provided by modern in-situ mass spectrometry also give evidence for large-spatial-scale large-amplitude atmospheric waves in the upper atmosphere and for a plethora of stable carbon-nitrile compounds above 1174 km. Furthermore, they allow the first direct measurements of isotopes of nitrogen, carbon, and argon, which provide interesting clues about the evolution of the atmosphere. The atmosphere was first accreted as ammonia and ammonia ices from the Saturn sub-nebula. Subsequent photochemistry likely converted the atmosphere into molecular nitrogen. The early atmosphere was 1.5 to 5 times more substantial and was lost via escape over the intervening 4.5 billion years due to the reduced gravity associated with the relatively small mass of Titan. Carbon in the form of methane has continued to outgas over time from the interior with much of it being deposited in the form of complex hydrocarbons on the surface and some of it also being lost to space.

  15. Radiation Design of Ion Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    Sittler, Ed; Cooper, John; Christian, Eric; Moore, Tom; Sturner, Steve; Paschalidis, Nick

    2011-01-01

    In the harsh radiation environment of Jupiter and with the JUpiter ICy moon Explorer (JUICE) mission including two Europa flybys where local intensities are approx. 150 krad/month behind 100 mils of Al shielding, so background from penetrating radiation can be a serious issue for detectors inside an Ion Mass Spectrometer (IMS). This can especially be important for minor ion detection designs. Detectors of choice for time-of-flight (TOF) designs are microchannel plates (MCP) and some designs may include solid state detectors (SSD). The standard approach is to use shielding designs so background event rates are low enough that the detector max rates and lifetimes are first not exceeded and then the more stringent requirement that the desired measurement can successfully be made (i.e., desired signal is sufficiently greater than background noise after background subtraction is made). GEANT codes are typically used along with various electronic techniques, but such designs need to know how the detectors will respond to the simulated primary and secondary radiations produced within the instrument. We will be presenting some preliminary measurements made on the response of MCPs to energetic electrons (20 ke V to 1400 ke V) using a Miniature TOF (MTOF) device and the High Energy Facility at Goddard Space Flight Center which has a Van de Graaff accelerator.

  16. Electron source for a mini ion trap mass spectrometer

    DOEpatents

    Dietrich, Daniel D.; Keville, Robert F.

    1995-01-01

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  17. Electron source for a mini ion trap mass spectrometer

    DOEpatents

    Dietrich, D.D.; Keville, R.F.

    1995-12-19

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  18. Non-destructive ion trap mass spectrometer and method

    DOEpatents

    Frankevich, Vladimir E.; Soni, Manish H.; Nappi, Mario; Santini, Robert E.; Amy, Jonathan W.; Cooks, Robert G.

    1997-01-01

    The invention relates to an ion trap mass spectrometer of the type having an ion trapping volume defined by spaced end caps and a ring electrode. The ion trap includes a small sensing electrode which senses characteristic motion of ions trapped in said trapping volume and provides an image current. Ions are excited into characteristic motion by application of an excitation pulse to the trapped ions. The invention also relates to a method of operating such an ion trap.

  19. Mass spectrometer and methods of increasing dispersion between ion beams

    DOEpatents

    Appelhans, Anthony D.; Olson, John E.; Delmore, James E.

    2006-01-10

    A mass spectrometer includes a magnetic sector configured to separate a plurality of ion beams, and an electrostatic sector configured to receive the plurality of ion beams from the magnetic sector and increase separation between the ion beams, the electrostatic sector being used as a dispersive element following magnetic separation of the plurality of ion beams. Other apparatus and methods are provided.

  20. Compact mass spectrometer for plasma discharge ion analysis

    DOEpatents

    Tuszewski, Michel G.

    1997-01-01

    A mass spectrometer and methods for mass spectrometry which are useful in characterizing a plasma. This mass spectrometer for determining type and quantity of ions present in a plasma is simple, compact, and inexpensive. It accomplishes mass analysis in a single step, rather than the usual two-step process comprised of ion extraction followed by mass filtering. Ions are captured by a measuring element placed in a plasma and accelerated by a known applied voltage. Captured ions are bent into near-circular orbits by a magnetic field such that they strike a collector, producing an electric current. Ion orbits vary with applied voltage and proton mass ratio of the ions, so that ion species may be identified. Current flow provides an indication of quantity of ions striking the collector.

  1. Compact mass spectrometer for plasma discharge ion analysis

    DOEpatents

    Tuszewski, M.G.

    1997-07-22

    A mass spectrometer and methods are disclosed for mass spectrometry which are useful in characterizing a plasma. This mass spectrometer for determining type and quantity of ions present in a plasma is simple, compact, and inexpensive. It accomplishes mass analysis in a single step, rather than the usual two-step process comprised of ion extraction followed by mass filtering. Ions are captured by a measuring element placed in a plasma and accelerated by a known applied voltage. Captured ions are bent into near-circular orbits by a magnetic field such that they strike a collector, producing an electric current. Ion orbits vary with applied voltage and proton mass ratio of the ions, so that ion species may be identified. Current flow provides an indication of quantity of ions striking the collector. 7 figs.

  2. High Mass Ion Detection with Charge Detector Coupled to Rectilinear Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Patil, Avinash A.; Chou, Szu-Wei; Chang, Pei-Yu; Lee, Chen-Wei; Cheng, Chun-Yen; Chu, Ming-Lee; Peng, Wen-Ping

    2016-12-01

    Conventional linear ion trap mass analyzers (LIT-MS) provide high ion capacity and show their MS n ability; however, the detection of high mass ions is still challenging because LIT-MS with secondary electron detectors (SED) cannot detect high mass ions. To detect high mass ions, we coupled a charge detector (CD) to a rectilinear ion trap mass spectrometer (RIT-MS). Immunoglobulin G ions (m/z 150,000) are measured successfully with controlled ion kinetic energy. In addition, when mass-to-charge (m/z) ratios of singly charged ions exceed 10 kTh, the detection efficiency of CD is found to be greater than that of SED. The CD can be coupled to LIT-MS to extend the detection mass range and provide the potential to perform MS n of high mass ions inside the ion trap.

  3. Simulating data processing for an Advanced Ion Mobility Mass Spectrometer

    SciTech Connect

    Chavarría-Miranda, Daniel; Clowers, Brian H.; Anderson, Gordon A.; Belov, Mikhail E.

    2007-11-03

    We have designed and implemented a Cray XD-1-based sim- ulation of data capture and signal processing for an ad- vanced Ion Mobility mass spectrometer (Hadamard trans- form Ion Mobility). Our simulation is a hybrid application that uses both an FPGA component and a CPU-based soft- ware component to simulate Ion Mobility mass spectrome- try data processing. The FPGA component includes data capture and accumulation, as well as a more sophisticated deconvolution algorithm based on a PNNL-developed en- hancement to standard Hadamard transform Ion Mobility spectrometry. The software portion is in charge of stream- ing data to the FPGA and collecting results. We expect the computational and memory addressing logic of the FPGA component to be portable to an instrument-attached FPGA board that can be interfaced with a Hadamard transform Ion Mobility mass spectrometer.

  4. Design and development of a fast ion mass spectrometer

    NASA Technical Reports Server (NTRS)

    Burch, J. L.

    1983-01-01

    Two Fast Ion Mass Spectrometers (FIMS A and FIMS B) were developed. The design, development, construction, calibration, integration, and flight of these instruments, along with early results from the data analysis efforts are summarized. A medium energy ion mass spectrometer that covers mass velocity space with significantly higher time resolution, improved mass resolution, (particularly for heavier ions), and wider energy range than existing instruments had achieved was completed. The initial design consisted of a dual channel cylindrical electrostatic analyzer followed by a dual channel cylindrical velocity filter. The gain versus count rate characteristics of the high current channel electron multipliers (CEM's), which were chosen for ion detection, revealed a systematic behavior that can be used as a criterion for selection of CEM's for long counting lifetimes.

  5. MASS SPECTROMETER

    DOEpatents

    White, F.A.

    1960-08-23

    A mass spectrometer is designed with a first adjustable magnetic field for resolving an ion beam into beams of selected masses, a second adjustable magnetic field for further resolving the ion beam from the first field into beams of selected masses, a thin foil disposed in the path of the beam between the first and second magnets to dissociate molecular ions incident thereon, an electrostatic field for further resolving the ion beam from the second field into beams of selected masses, and a detector disposed adjacent to the electrostatic field to receive the ion beam.

  6. A retarding ion mass spectrometer for the Dynamics Explorer-1

    NASA Technical Reports Server (NTRS)

    Wright, W.

    1985-01-01

    The Retarding Ion Mass Spectrometer (RIMS) for Dynamics Explorer-1 is an instrument designed to measure the details of the thermal plasma distribution. It combines the ion temperature determining capability of the retarding potential analyzer with the compositional capabilities of the mass spectrometer and adds multiple sensor heads to sample all directions relative to the spacecraft ram direction. This manual provides a functional description of the RIMS, the instrument calibration, and a description of the commands which can be stored in the instrument logic to control its operation.

  7. Mini Mass Spectrometer Integrated with a Miniature Ion Funnel.

    PubMed

    Zhai, Yanbing; Zhang, Xiaohua; Xu, Hualei; Zheng, Yongchang; Yuan, Tao; Xu, Wei

    2017-03-14

    Previously, a continuous atmospheric pressure interfaced miniature mass spectrometer was developed in our lab. The continuous atmospheric pressure interface improves system robustness, stability, and scan speed, but it also results in limited ion transfer efficiency and reduced mass resolution. To solve these problems, a miniature ion funnel was designed and integrated into the miniature mass spectrometer for the first time. Besides ion transfer efficiency, dimension and power consumption of the ion funnel also need to be considered throughout the design process. After a systematic optimization, the designed miniature ion funnel could increase ion transfer efficiency by more than 10 times, while lowering the background pressure of ion trap by ∼2 times. As a result, sensitivity and mass resolution of the second generation miniature mass spectrometer were improved by 20 times and ∼2 times, respectively, while maintaining its high scan speed and stability. A sensitive and robust mini-MS, capable of coupling with ambient ionization sources would meet the needs of many on-site chemical analysis applications, such as in food, drug, and agricultural administrations, forensic science, homeland security, and etc.

  8. Ion Mass Spectrometer Development for JEO Class Missions

    NASA Astrophysics Data System (ADS)

    Sittler, E. C.; Cooper, J. F.; Paschalidis, N.; Coplan, M. A.; Chornay, D. J.; Sturner, S. J.; Brown, S. K.; Hartle, R. E.; Paterson, W. R.

    2012-10-01

    Under the Astrobiology Instrument Development Program we have been developing an advanced 3-D ion mass spectrometer (IMS) from 10 V to 30 kV, that can be proposed for missions to Jupiter's icy moons, Uranus, Titan, asteroids, comets, and solar wind.

  9. Linear electronic field time-of-flight ion mass spectrometers

    DOEpatents

    Funsten, Herbert O.

    2010-08-24

    Time-of-flight mass spectrometer comprising a first drift region and a second drift region enclosed within an evacuation chamber; a means of introducing an analyte of interest into the first drift region; a pulsed ionization source which produces molecular ions from said analyte of interest; a first foil positioned between the first drift region and the second drift region, which dissociates said molecular ions into constituent atomic ions and emits secondary electrons; an electrode which produces secondary electrons upon contact with a constituent atomic ion in second drift region; a stop detector comprising a first ion detection region and a second ion detection region; and a timing means connected to the pulsed ionization source, to the first ion detection region, and to the second ion detection region.

  10. Ion mass spectrometer experiment for ISIS-2 spacecraft

    NASA Technical Reports Server (NTRS)

    Hoffman, John H.

    1987-01-01

    The International Satellite for Ionospheric Studies (ISIS) program of NASA was the longest duration program in NASA history. A number of satellites were flown under this program, the last being called ISIS-2, which was launched on April 1, 1971 and operated successfully for over 13 years. An experiment called the Ion Mass Spectrometer (IMS) was flown on the ISIS-2 spacecraft. It operated for 10 years providing a large data base of positive ion composition and ion flow velocities along the orbit of the satellite, the latter being circular at 1400 km with a 90 degree inclination. The data were processed and reside in the National Space Sciences Data Center.

  11. Personal computer based Fourier transform ion cyclotron resonance mass spectrometer

    NASA Astrophysics Data System (ADS)

    Guan, Shenheng; Jones, Patrick R.

    1988-12-01

    An IBM PC AT compatible computer is used to host the interface of a Fourier transform ion cyclotron resonance mass spectrometer or FTMS. A common fast memory bank for both ion-excitation waveform and data acquisition is reserved in the computer's system memory space. All the digital electronics circuitry is assembled on an IBM PC AT extension board. Neither an external frequency synthesizer nor a waveform digitizer is needed. Ion-excitation waveforms can be generated in either frequency-sweeping or inverse-Fourier transform modes. Both excitation and data acquisition can be carried out at eight megawords per second.

  12. The magnetic ion-mass spectrometer on Atmosphere Explorer.

    NASA Technical Reports Server (NTRS)

    Hoffman, J. H.; Hanson, W. B.; Lippincott, C. R.; Ferguson , E. E.

    1973-01-01

    The magnetic ion-mass spectrometer is designed to measure the abundances of the ambient positive ions in the ionosphere. It will be calibrated in flight against the retarding-potential analyzer and the cylindrical electrostatic probe to give absolute concentration data for the ion species detected. These parameters can be measured to approximately plus or minus 10% in well-behaved regions where concentrations are above 1000/cu cm. However, in highly structured polar regions, some degradation in accuracy may be expected. Three mass ranges, covered simultaneously by the scan of the instrument, 1 to 4, 4 to 16, and 16 to 64 amu, permit measurement of the entire mass range, 1 to 64 amu, in 1 sec in the main (peaks) mode. An alternate mode, analog-long, will extend the mass range to 90 amu with a 9-sec period.

  13. Quadrupole Ion/Neutral Mass Spectrometer for Space Shuttle Applications.

    DTIC Science & Technology

    1986-04-07

    fCon linue on reverse if neeec’O ond ientify by block number) _ A Quadrupole Ion/Neutral Mass Spectrometer (QINMS) was developed for the fourth flight...The charging of spacecraft surfaces, Rev. Geophys. and Space Phys. 19:577-616. 16. Paul , W., Rheinhard, H. P., and von Zahn, U. (1958) Das elektrische...massenfilter als massenspektrometer und isotopentrenner, Z. Ph sik 152:143-182. Paul , W., and Steinwedel, H. (1953) Z. Naturforsch 8a:448. Paul , W

  14. Cassini-Huygens Ion Neutral Mass Spectrometer and the Future

    NASA Astrophysics Data System (ADS)

    Waite, J. Hunter

    2014-05-01

    The Cassini-Huygens Ion Neutral Mass Spectrometer (Cassini INMS) designed and built by Hasso Niemann has revolutionized our understanding of the Saturn system and demonstrated the importance of mass spectrometry as a tool for understanding formation, evolution, and chemical processes. In this talk that honors the accomplishments of Hasso I will discuss: 1) the major discoveries of INMS at Titan, Enceladus, and the other icy moons of Saturn, 2) the new perspective this has given us on understanding the formation and evolution of the outer solar system, and 3) the implications for future studies in the outer solar system using mass spectrometry.

  15. Linear electric field time-of-flight ion mass spectrometer

    DOEpatents

    Funsten, Herbert O.; Feldman, William C.

    2008-06-10

    A linear electric field ion mass spectrometer having an evacuated enclosure with means for generating a linear electric field located in the evacuated enclosure and means for injecting a sample material into the linear electric field. A source of pulsed ionizing radiation injects ionizing radiation into the linear electric field to ionize atoms or molecules of the sample material, and timing means determine the time elapsed between ionization of atoms or molecules and arrival of an ion out of the ionized atoms or molecules at a predetermined position.

  16. Titan's Topside Ionospheric Composition: Cassini Plasma Spectrometer Ion Mass Spectrometer Measurements

    NASA Astrophysics Data System (ADS)

    Sittler, Edward; Hartle, Richard; Ali, Ashraf; Cooper, John; Lipatov, Alexander; Simpson, David; Sarantos, Menelaos; Chornay, Dennis; Smith, Todd

    2017-01-01

    We present ion composition measurements of Titan's topside ionosphere using both T9 and T15 Cassini Plasma Spectrometer (CAPS) Ion Mass Spectrometer (IMS) measurements. The IMS is able to make measurements of Titan's ionosphere due to ionospheric outflows as originally reported for the T9 flyby. This allows one to take advantage of the unique capabilities of the CAPS IMS which measures both the mass-per-charge (M/Q) of the ions and the fragments of the ions produced inside the sensor such as carbon, nitrogen and oxygen fragments. Specific attention will be given to such ions as NH4 +, N +, O +, CH4 +, CxHy +, and HCNH + ions as examples. The CAPS IMS uses a time-of-flight (TOF) technique which accelerates ions up to 14.6 kV, so they can pass through ultra-thin carbon foils. Neutral fragments are used to measure the ion M/Q and positive fragments to measure the atomic components. We preliminarily find, by using IMS measurements of T9 and T15 ionospheric outflows, evidence for methane group ions, nitrogen ions, ammonium ions, water group ions and CnHm + ions with n = 2, 3, and 4 within Titan's topside ionosphere. E.C. Sittler acknowledges support at Goddard Space Flight Center by the CAPS Cassini Project from JPL funds under contract # NAS703001TONMO711123/1405851.

  17. "Fast Excitation" CID in Quadrupole Ion Trap Mass Spectrometer

    SciTech Connect

    Murrell, J.; Despeyroux, D.; Lammert, Stephen {Steve} A; Stephenson Jr, James {Jim} L; Goeringer, Doug

    2003-01-01

    Collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer is usually performed by applying a small amplitude excitation voltage at the same secular frequency as the ion of interest. Here we disclose studies examining the use of large amplitude voltage excitations (applied for short periods of time) to cause fragmentation of the ions of interest. This process has been examined using leucine enkephalin as the model compound and the motion of the ions within the ion trap simulated using ITSIM. The resulting fragmentation information obtained is identical with that observed by conventional resonance excitation CID. ''Fast excitation'' CID deposits (as determined by the intensity ratio of the a{sub 4}/b{sub 4} ion of leucine enkephalin) approximately the same amount of internal energy into an ion as conventional resonance excitation CID where the excitation signal is applied for much longer periods of time. The major difference between the two excitation techniques is the higher rate of excitation (gain in kinetic energy) between successive collisions with helium atoms with ''fast excitation'' CID as opposed to the conventional resonance excitation CID. With conventional resonance excitation CID ions fragment while the excitation voltage is still being applied whereas for ''fast excitation'' CID a higher proportion of the ions fragment in the ion cooling time following the excitation pulse. The fragmentation of the (M + 17H){sup 17+} of horse heart myoglobin is also shown to illustrate the application of ''fast excitation'' CID to proteins.

  18. Miniature Ion Optics Towards a Micro Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Chaudhary, Ashish

    This PhD dissertation reports the development of miniature ion optics components of a mass spectrometer (MS) with the ultimate goal to lay the foundation for a compact low-power micromachined MS (microMS) for broad-range chemical analysis. Miniaturization of two specific components a) RF ion traps and b) an ion funnel have been investigated and miniature low-power versions of these components have been developed and demonstrated successfully in lab experiments. Power savings, simpler electronics and packaging schemes required to operate the micro-scale RF cylindrical ion traps have been the key motivation driving this research. Microfabricated cylindrical ion traps (microCITs) and arrays in silicon, silicon-on-insulator and stainless steel substrates have been demonstrated and average power of as low as 55 mW for a low mass range (28 to 136 amu) and mass spectra with better than a unit-mass-resolution have been recorded. For the ion funnel miniaturization effort, simple assembly, small form factor and ease of integration have been emphasized. A simplification of the conventional 3D ion funnel design, called the planar ion funnel, has been developed in a single plate and has been tested to demonstrate ion funneling at medium vacuum levels (1E-5 Torr) using DC voltages and power less than 0.5 W. Miniaturization of these components also enables use of other novel ion optics components, packaging and integration, which will allow a new class of microMS architectures amenable for radical miniaturization.

  19. An ion mobility mass spectrometer for investigating photoisomerization and photodissociation of molecular ions.

    PubMed

    Adamson, B D; Coughlan, N J A; Markworth, P B; Continetti, R E; Bieske, E J

    2014-12-01

    An ion mobility mass spectrometry apparatus for investigating the photoisomerization and photodissociation of electrosprayed molecular ions in the gas phase is described. The device consists of a drift tube mobility spectrometer, with access for a laser beam that intercepts the drifting ion packet either coaxially or transversely, followed by a quadrupole mass filter. An ion gate halfway along the drift region allows the instrument to be used as a tandem ion mobility spectrometer, enabling mobility selection of ions prior to irradiation, with the photoisomer ions being separated over the second half of the drift tube. The utility of the device is illustrated with photoisomerization and photodissociation action spectra of carbocyanine molecular cations. The mobility resolution of the device for singly charged ions is typically 80 and it has a mass range of 100-440 Da, with the lower limit determined by the drive frequency for the ion funnels, and the upper limit by the quadrupole mass filter.

  20. An ion mobility mass spectrometer for investigating photoisomerization and photodissociation of molecular ions

    SciTech Connect

    Adamson, B. D.; Coughlan, N. J. A.; Markworth, P. B.; Bieske, E. J.; Continetti, R. E.

    2014-12-15

    An ion mobility mass spectrometry apparatus for investigating the photoisomerization and photodissociation of electrosprayed molecular ions in the gas phase is described. The device consists of a drift tube mobility spectrometer, with access for a laser beam that intercepts the drifting ion packet either coaxially or transversely, followed by a quadrupole mass filter. An ion gate halfway along the drift region allows the instrument to be used as a tandem ion mobility spectrometer, enabling mobility selection of ions prior to irradiation, with the photoisomer ions being separated over the second half of the drift tube. The utility of the device is illustrated with photoisomerization and photodissociation action spectra of carbocyanine molecular cations. The mobility resolution of the device for singly charged ions is typically 80 and it has a mass range of 100-440 Da, with the lower limit determined by the drive frequency for the ion funnels, and the upper limit by the quadrupole mass filter.

  1. Continuous time-of-flight ion mass spectrometer

    DOEpatents

    Funsten, Herbert O.; Feldman, William C.

    2004-10-19

    A continuous time-of-flight mass spectrometer having an evacuated enclosure with means for generating an electric field located in the evacuated enclosure and means for injecting a sample material into the electric field. A source of continuous ionizing radiation injects ionizing radiation into the electric field to ionize atoms or molecules of the sample material, and timing means determine the time elapsed between arrival of a secondary electron out of said ionized atoms or molecules at a first predetermined location and arrival of a sample ion out of said ionized atoms or molecules at a second predetermined location.

  2. Improved ion optics for introduction of ions into a 9.4-T Fourier transform ion cyclotron resonance mass spectrometer

    SciTech Connect

    Chen, Yu; Leach, Franklin E.; Kaiser, Nathan K.; Dang, Xibei; Ibrahim, Yehia M.; Norheim, Randolph V.; Anderson, Gordon A.; Smith, Richard D.; Marshall, Alan G.

    2015-01-19

    Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry provides unparalleled mass accuracy and resolving power.[1],[2] With electrospray ionization (ESI), ions are typically transferred into the mass spectrometer through a skimmer, which serves as a conductance-limiting orifice. However, the skimmer allows only a small fraction of incoming ions to enter the mass spectrometer. An ion funnel, originally developed by Smith and coworkers at Pacific Northwest National Laboratory (PNNL)[3-5] provides much more efficient ion focusing and transfer. The large entrance aperture of the ion funnel allows almost all ions emanating from a heated capillary to be efficiently captured and transferred, resulting in nearly lossless transmission.

  3. 10 K Ring Electrode Trap - Tandem Mass Spectrometer for Infrared Spectroscopy of Mass Selected Ions

    SciTech Connect

    Goebbert, Daniel J.; Meijer, Gerard; Asmis, Knut R.

    2009-03-17

    A novel instrumental setup for measuring infrared photodissociation spectra of buffer gas cooled, mass-selected ions is described and tested. It combines a cryogenically cooled, linear radio frequency ion trap with a tandem mass spectrometer, optimally coupling continuous ion sources to pulsed laser experiments. The use of six independently adjustable DC potentials superimposed over the trapping radio frequency field provides control over the ion distribution within, as well as the kinetic energy distribution of the ions extracted from the ion trap. The scheme allows focusing the ions in space and time, such that they can be optimally irradiated by a pulsed, widely tunable infrared photodissociation laser. Ion intensities are monitored with a time-of-flight mass spectrometer mounted orthogonally to the ion trap axis.

  4. Light ion mass spectrometer for space-plasma investigations

    NASA Technical Reports Server (NTRS)

    Reasoner, D. L.; Chappell, C. R.; Fields, S. A.; Lewter, W. J.

    1982-01-01

    Direct satellite measurements and ground-based techniques have given a comprehensive view of the density distribution of the cold plasma population in the earth's magnetosphere. There were, however, no direct measurements of the low-energy plasma mass composition, temperature, density, pitch-angle distribution, or plasma flow velocity. A description is presented of the evolution and development of an instrument, the Light Ion Mass Spectrometer (LIMS), designed to make these low-energy plasma measurements. The instrument was developed for flight on the spacecraft SCA-THA, a satellite to study satellite charging at high altitudes. This satellite, whose primary mission was to study spacecraft-plasma interactions and electrostatic charging, was launched into a near-geosynchronous orbit. The design requirements regarding the instrument are discussed, and attention is given to the calibration procedures, the flight configuration, and some examples of flight data.

  5. A hand-portable digital linear ion trap mass spectrometer.

    PubMed

    Xue, Bing; Sun, Lulu; Huang, Zhengxu; Gao, Wei; Fan, Rongrong; Cheng, Ping; Ding, Li; Ma, Li; Zhou, Zhen

    2016-10-07

    A hand-portable digital linear ion trap mass spectrometer (DLIT-MS) has been developed for VOC analysis. It has a weight of 18 kg with dimensions of 49 cm × 39 cm × 16 cm, and consumes an average power of ca. 60 W. As a result of the introduction of a digital waveform, the DLIT-MS can be driven at a lower voltage (±100 V) to cover a mass range of 30-300 Th with a unit resolution. Compact electronics has been designed to control the DLIT-MS and record mass spectra. The mass drift was reduced after the improvement in electronics to stabilize the digital waveform voltage during the mass scan. Tandem mass spectrometry (MS) has been achieved by using digital asymmetric waveform isolation (DAWI), forward and reverse scan, and collision induced dissociation (CID). The isolation and CID efficiency for methyl salicylate were 83.9% and 81.3%, respectively. A novel buffer gas inlet system was designed to enhance the sensitivity and allow easy and safe use of the instrument. Limits of detection below 1 ppbv were obtained for several mixed gaseous samples.

  6. SCAPS, a two-dimensional ion detector for mass spectrometer

    NASA Astrophysics Data System (ADS)

    Yurimoto, Hisayoshi

    2014-05-01

    Faraday Cup (FC) and electron multiplier (EM) are of the most popular ion detector for mass spectrometer. FC is used for high-count-rate ion measurements and EM can detect from single ion. However, FC is difficult to detect lower intensities less than kilo-cps, and EM loses ion counts higher than Mega-cps. Thus, FC and EM are used complementary each other, but they both belong to zero-dimensional detector. On the other hand, micro channel plate (MCP) is a popular ion signal amplifier with two-dimensional capability, but additional detection system must be attached to detect the amplified signals. Two-dimensional readout for the MCP signals, however, have not achieve the level of FC and EM systems. A stacked CMOS active pixel sensor (SCAPS) has been developed to detect two-dimensional ion variations for a spatial area using semiconductor technology [1-8]. The SCAPS is an integrated type multi-detector, which is different from EM and FC, and is composed of more than 500×500 pixels (micro-detectors) for imaging of cm-area with a pixel of less than 20 µm in square. The SCAPS can be detected from single ion to 100 kilo-count ions per one pixel. Thus, SCAPS can be accumulated up to several giga-count ions for total pixels, i.e. for total imaging area. The SCAPS has been applied to stigmatic ion optics of secondary ion mass spectrometer, as a detector of isotope microscope [9]. The isotope microscope has capabilities of quantitative isotope images of hundred-micrometer area on a sample with sub-micrometer resolution and permil precision, and of two-dimensional mass spectrum on cm-scale of mass dispersion plane of a sector magnet with ten-micrometer resolution. The performance has been applied to two-dimensional isotope spatial distribution for mainly hydrogen, carbon, nitrogen and oxygen of natural (extra-terrestrial and terrestrial) samples and samples simulated natural processes [e.g. 10-17]. References: [1] Matsumoto, K., et al. (1993) IEEE Trans. Electron Dev. 40

  7. Ion Mass Spectrometer for Sporadic-E Rocket Experiments

    NASA Technical Reports Server (NTRS)

    Heelis, R. A.; Earle, G. D.; Pfaff, Robert

    2000-01-01

    NASA grant NAG5-5086 provided funding for the William B. Hanson Center for Space Sciences at the University of Texas at Dallas (UTD) to design, fabricate, calibrate, and ultimately fly two ion mass spectrometer instruments on a pair of sounding rocket payloads. Drs. R.A. Heelis and G.D. Earle from UTD were co-investigators on the project. The principal investigator for both rocket experiments was Dr. Robert Pfaff of the Goddard Space Flight Center. The overall project title was "Rocket/Radar Investigation of Lower Ionospheric Electrodynamics Associated with Intense Mid-Latitude Sporadic-E Layers". This report describes the overall objectives of the project, summarizes the instrument design and flight experiment details, and presents representative data obtained during the flights.

  8. Double focusing ion mass spectrometer of cylindrical symmetry

    NASA Technical Reports Server (NTRS)

    Coplan, M. A.; Moore, J. H.; Hoffman, R. A.

    1984-01-01

    A mass spectrometer consisting of an electric sector followed by a magnetic sector is described. The geometry is a cylindrically symmetric generalization of the Mattauch-Herzog spectrometer (1934). With its large annular entrance aperture and a position-sensitive detector, the instrument provides a large geometric factor and 100-percent duty factor, making it appropriate for spacecraft experiments.

  9. Ion-optical studies for improved ion transmission in multistage isotope-ratio mass spectrometers

    SciTech Connect

    Stoffels, J.J. ); Laue, H.J. )

    1991-10-01

    Theoretical and experimental ion-optical studies of multistage isotope-ratio mass spectrometers were conducted to determine what improvement in ion transmission efficiency might be attainable through design changes. The computer program GIOS (General Ion Optical Systems) was used to perform theoretical calculations of focusing properties and ion transmission efficiency. Actual transmission through multiple-sector instruments was determined from measurements of the ion beam vertical profile at the focus of each stage. For existing mass spectrometers with tandem magnets of normal geometry, our studies determined a feasible design change that significantly increases ion transmission through the analyzer. The use of a cylindrical einzel lens or an electrostatic quadrupole lens near the focal point between the magnets provides vertical focusing of the ion beam to achieve the improved transmission. We also established a new mass spectrometer design that give 100% transmission through tandem magnetic analyzers and through a third-stage electrostatic analyzer without the use of an intermediate focusing lens. Non-normal magnetic field boundaries provide ion beam focusing in the vertical plant to achieve this complete transmission. 19 refs., 27 figs., 3 tabs.

  10. Hot ions observed by the Giotto ion mass spectrometer inside the Comet Halley contact surface

    NASA Technical Reports Server (NTRS)

    Goldstein, R.; Young, D. T.; Balsiger, H.; Buehler, F.; Goldstein, B. E.; Neugebauer, M.; Rosenbauer, H.; Schwenn, R.; Shelly, E. G.

    1986-01-01

    Just inside the contact surface (approx. 4700 km) the High Energy Range Spectrometer (HERS) sensor of the Giotto ion mass spectrometer detected a sudden, intense burst of ions that lasted until the HERS sensor ceased transmitting data at a distance 3000 km from comet Halley. During this interval ions with M/Q=1, 2, 12, 14, 16, 19, 24 and 28 were observed. The heavier ions appear in two populations (in the S/C frame): a very low energy, almost omnidirectional distribution, and a more energetic (approx. < ram speed) population coming from the ram direction. The low energy ions may belong to the natural Halley environment or be generated at the spacecraft by dust and gas bombardment. The ions may also be related to spacecraft charging processes on Giotto.

  11. Quadrupole Ion Mass Spectrometer for Masses of 2 to 50 Da

    NASA Technical Reports Server (NTRS)

    Helms, William; Griffin, Timothy P.; Ottens, Andrew; Harrison, Willard

    2005-01-01

    A customized quadrupole ion-trap mass spectrometer (QITMS) has been built to satisfy a need for a compact, rugged instrument for measuring small concentrations of hydrogen, helium, oxygen, and argon in a nitrogen atmosphere. This QITMS can also be used to perform quantitative analyses of other gases within its molecular-mass range, which is 2 to 50 daltons (Da). (More precisely, it can be used to perform quantitative analysis of gases that, when ionized, are characterized by m/Z ratios between 2 and 50, where m is the mass of an ion in daltons and Z is the number of fundamental electric charges on the ion.

  12. Fast neutral beam ion source coupled to a Fourier transform ion cyclotron resonance mass spectrometer

    SciTech Connect

    Hill, N.C.; Limbach, P.A.; Shomo, R.E. II; Marshall, A.G. ); Appelhans, A.D.; Delmore, J.E. )

    1991-11-01

    The coupling of an autoneutralizing SF{sup {minus}}{sub 6} fast ion-beam gun to a Fourier transform ion cyclotron resonance (FT/ICR) mass spectrometer is described. The fast neutral beam provides for secondary-ion-type FT/ICR mass analysis (e.g., production of abundant pseudomolecular (M+H){sup +} ions) of involatile samples without the need for external ion injection, since ions are formed at the entrance to the ICR ion trap. The design, construction, and testing of the hybrid instrument are described. The feasibility of the experiment (for both broadband and high-resolution FT/ICR positive-ion mass spectra) is demonstrated with {ital tetra}-butylammonium bromide and a Tylenol{sup ( )} sample. The ability to analyze high molecular weight polymers with high mass resolution is demonstrated for Teflon{sup ( )}. All of the advantages of the fast neutral beam ion source previously demonstrated with quadrupole mass analysis are preserved, and the additional advantages of FT/ICR mass analysis (e.g., high mass resolving power, ion trapping) are retained.

  13. Fast neutral beam ion source coupled to a Fourier transform ion cyclotron resonance mass spectrometer

    NASA Astrophysics Data System (ADS)

    Hill, Nicholas C.; Limbach, Patrick A.; Shomo, Ronald E., II; Marshall, Alan G.; Appelhans, Anthony D.; Delmore, James E.

    1991-11-01

    The coupling of an autoneutralizing SF-6 fast ion-beam gun to a Fourier transform ion cyclotron resonance (FT/ICR) mass spectrometer is described. The fast neutral beam provides for secondary-ion-type FT/ICR mass analysis [e.g., production of abundant pseudomolecular (M+H)+ ions] of involatile samples without the need for external ion injection, since ions are formed at the entrance to the ICR ion trap. The design, construction, and testing of the hybrid instrument are described. The feasibility of the experiment (for both broadband and high-resolution FT/ICR positive-ion mass spectra) is demonstrated with tetra-butylammonium bromide and a Tylenol■ sample. The ability to analyze high molecular weight polymers with high mass resolution is demonstrated for Teflon■. All of the advantages of the fast neutral beam ion source previously demonstrated with quadrupole mass analysis are preserved, and the additional advantages of FT/ICR mass analysis (e.g., high mass resolving power, ion trapping) are retained.

  14. Improved ion optics for introduction of ions into a 9.4-T Fourier transform ion cyclotron resonance mass spectrometer

    DOE PAGES

    Chen, Yu; Leach, Franklin E.; Kaiser, Nathan K.; ...

    2015-01-19

    Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry provides unparalleled mass accuracy and resolving power.[1],[2] With electrospray ionization (ESI), ions are typically transferred into the mass spectrometer through a skimmer, which serves as a conductance-limiting orifice. However, the skimmer allows only a small fraction of incoming ions to enter the mass spectrometer. An ion funnel, originally developed by Smith and coworkers at Pacific Northwest National Laboratory (PNNL)[3-5] provides much more efficient ion focusing and transfer. The large entrance aperture of the ion funnel allows almost all ions emanating from a heated capillary to be efficiently captured and transferred, resulting inmore » nearly lossless transmission.« less

  15. The effective temperature of ions stored in a linear quadrupole ion trap mass spectrometer.

    PubMed

    Donald, William A; Khairallah, George N; O'Hair, Richard A J

    2013-06-01

    The extent of internal energy deposition into ions upon storage, radial ejection, and detection using a linear quadrupole ion trap mass spectrometer is investigated as a function of ion size (m/z 59 to 810) using seven ion-molecule thermometer reactions that have well characterized reaction entropies and enthalpies. The average effective temperatures of the reactants and products of the ion-molecule reactions, which were obtained from ion-molecule equilibrium measurements, range from 295 to 350 K and do not depend significantly on the number of trapped ions, m/z value, ion trap q z value, reaction enthalpy/entropy, or the number of vibrational degrees of freedom for the seven reactions investigated. The average of the effective temperature values obtained for all seven thermometer reactions is 318 ± 23 K, which indicates that linear quadrupole ion trap mass spectrometers can be used to study the structure(s) and reactivity of ions at near ambient temperature.

  16. Improved ion optics for introduction of ions into a 9.4-T Fourier transform ion cyclotron resonance mass spectrometer.

    PubMed

    Chen, Yu; Leach, Franklin E; Kaiser, Nathan K; Dang, Xibei; Ibrahim, Yehia M; Norheim, Randolph V; Anderson, Gordon A; Smith, Richard D; Marshall, Alan G

    2015-01-01

    Enhancements to the ion source and transfer optics of our 9.4 T Fourier transform ion cyclotron resonance (ICR) mass spectrometer have resulted in improved ion transmission efficiency for more sensitive mass measurement of complex mixtures at the MS and MS/MS levels. The tube lens/skimmer has been replaced by a dual ion funnel and the following octopole by a quadrupole for reduced ion cloud radial expansion before transmission into a mass-selective quadrupole. The number of ions that reach the ICR cell is increased by an order of magnitude for the funnel/quadrupole relative to the tube lens/skimmer/octopole.

  17. Composition measurements of the topside ionosphere using a magnetic mass spectrometer, ion mass spectrometer on ISIS-2 spacecraft

    NASA Technical Reports Server (NTRS)

    Hoffman, J. H.

    1975-01-01

    The ion mass spectrometer (IMS) on the ISIS-II satellite is described; it measures the composition and distribution of positive ions in the earth's ionosphere in the mass range of 1 to 64 atomic mass units. Significant data were received which show a wide variation in ion composition at night near the equator and in the daytime poleward of the plasmapause. It was found that these data enable further study of the polar wind and that the experiment produced timely data during the August, 1972 magnetic storm to show the development of a unique ionosphere above the plasmapause during the period of the storm. The scientific objectives and results of the experiment, the technical description of the instrument, a bibliography with sample papers attached, and a summary of recommendations for further study are presented.

  18. Ion/molecule reactions for detecting ammonia using miniature cylindrical ion trap mass spectrometers.

    PubMed

    Smith, Jonell N; Keil, Adam D; Noll, Robert J; Cooks, R Graham

    2011-01-07

    Gaseous ammonia, a common toxic industrial compound, is not detected readily in ion trap mass spectrometers because its molecular ion falls below the low-mass cutoff (~m/z 40) normally used when examining organic compounds. Instead, reactions of ammonia with halobenzene radical cations were used with internal electron ionization in two cylindrical ion trap miniature mass spectrometers to create a characteristic product ion by which to identify and quantify ammonia. Ammonia showed a linear response over the concentration range studied (parts per million [ppm] to parts per billion [ppb]) with limits of detection of 17 ppm and 220 ppb for experiments involving direct introduction and thermal desorption after pre-concentration, respectively. These values are comparable to ammonia's permissible exposure limit (50 ppm) and odor threshold (5 ppm). Receiver operating characteristic (ROC) curves were used to describe the method sensitivity, the probability of true positives, and the false positive rate for ammonia. A customized reaction scan function was created to select the species available for the ion/molecule reaction and set the amount of time the product ion could be accumulated in the trap. Product ion identity was verified using tandem mass spectrometry. Similar reactions with methylamine, ethylamine and the two nitriles, acetonitrile and benzonitrile, were explored.

  19. Implementation of Ion/Ion Reactions in a Quadrupole/Time-of-Flight Tandem Mass Spectrometer

    PubMed Central

    Xia, Yu; Chrisman, Paul A.; Erickson, David E.; Liu, Jian; Liang, Xiaorong; Londry, Frank A.; Yang, Min J.; McLuckey, Scott A.

    2008-01-01

    A commercial quadrupole/time-of-flight (QqTOF) tandem mass spectrometer has been adapted for ion/ion reaction studies. To enable mutual storage of oppositely charged ions in a linear ion trap, the oscillating quadrupole field of the second quadrupole of the system (Q2) serves to store ions in the radial dimension while auxiliary RF is superposed on the end lenses of Q2 during the reaction period to create barriers in the axial dimension. A pulsed dual electrospray (ESI) source is directly coupled to the instrument interface for the purpose of proton transfer reactions. Singly and doubly charged protein ions as high in mass as 66 kDa are readily formed and observed after proton transfer reactions. For the modified instrument, the mass resolving power is about 8000 for a wide m/z range and the mass accuracy is ~20 ppm for external calibration and ~5 ppm for internal calibration after ion/ion reactions. Parallel ion parking is demonstrated with a six-component protein mixture, which shows the potential application of reducing spectral complexity and concentrating certain charge states. The current system has high flexibility with respect to defining MSn experiments involving collision-induced dissociation (CID) and ion/ion reactions. Protein precursor and CID product masses can be determined with good accuracy, providing an attractive platform for top-down proteomics. Electron transfer dissociation (ETD) ion/ion reactions are implemented by using a pulsed nano-ESI/atmospheric pressure chemical ionization (APCI) dual source for ionization. The reaction between protonated peptide ions and radical anions of 1,3-dinitrobenzene formed exclusively c- and z- type fragment ions. PMID:16771545

  20. UV photodissociation of trapped ions following ion mobility separation in a Q-ToF mass spectrometer.

    PubMed

    Bellina, Bruno; Brown, Jeffery M; Ujma, Jakub; Murray, Paul; Giles, Kevin; Morris, Michael; Compagnon, Isabelle; Barran, Perdita E

    2014-12-21

    An ion mobility mass spectrometer has been modified to allow optical interrogation of ions with different mass-to-charge (m/z) ratios and/or mobilities (K). An ion gating and trapping procedure has been developed which allows us to store ions for several seconds enabling UV photodissociation (UVPD).

  1. Towards a universal product ion mass spectral library - reproducibility of product ion spectra across eleven different mass spectrometers.

    PubMed

    Hopley, Chris; Bristow, Tony; Lubben, Anneke; Simpson, Alec; Bull, Elaine; Klagkou, Katerina; Herniman, Julie; Langley, John

    2008-06-01

    Product ion spectra produced by collision-induced dissociation (CID) in tandem mass spectrometry experiments can differ markedly between instruments. There have been a number of attempts to standardise the production of product ion spectra; however, a consensus on the most appropriate approach to the reproducible production of spectra has yet to be reached. We have previously reported the comparison of product ion spectra on a number of different types of instruments - a triple quadrupole, two ion traps and a Fourier transform ion cyclotron resonance mass spectrometer (Bristow AWT, Webb KS, Lubben AT, Halket JM. Rapid Commun. Mass Spectrom. 2004; 18: 1). The study showed that a high degree of reproducibility was achievable. The goal of this study was to improve the comparability and reproducibility of CID product ion mass spectra produced in different laboratories and using different instruments. This was carried out experimentally by defining a spectral calibration point on each mass spectrometer for product ion formation. The long-term goal is the development of a universal (instrument independent) product ion mass spectral library for the identification of unknowns. The spectra of 48 compounds have been recorded on eleven mass spectrometers: six ion traps, two triple quadrupoles, a hybrid triple quadrupole, and two quadrupole time-of-flight instruments. Initially, 4371 spectral comparisons were carried out using the data from eleven instruments and the degree of reproducibility was evaluated. A blind trial has also been carried out to assess the reproducibility of spectra obtained during LC/MS/MS. The results suggest a degree of reproducibility across all instrument types using the tuning point technique. The reproducibility of the product ion spectra is increased when comparing the tandem in time type instruments and the tandem in space instruments as two separate groups. This may allow the production of a more limited, yet useful, screening library for LC

  2. 21 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Greatly Expands Mass Spectrometry Toolbox

    NASA Astrophysics Data System (ADS)

    Shaw, Jared B.; Lin, Tzu-Yung; Leach, Franklin E.; Tolmachev, Aleksey V.; Tolić, Nikola; Robinson, Errol W.; Koppenaal, David W.; Paša-Tolić, Ljiljana

    2016-12-01

    We provide the initial performance evaluation of a 21 Tesla Fourier transform ion cyclotron resonance mass spectrometer operating at the Environmental Molecular Sciences Laboratory at the Pacific Northwest National Laboratory. The spectrometer constructed for the 21T system employs a commercial dual linear ion trap mass spectrometer coupled to a FTICR spectrometer designed and built in-house. Performance gains from moving to higher magnetic field strength are exemplified by the measurement of peptide isotopic fine structure, complex natural organic matter mixtures, and large proteins. Accurate determination of isotopic fine structure was demonstrated for doubly charged Substance P with minimal spectral averaging, and 8158 molecular formulas assigned to Suwannee River Fulvic Acid standard with root-mean-square (RMS) error of 10 ppb. We also demonstrated superior performance for intact proteins; namely, broadband isotopic resolution of the entire charge state distribution of apo-transferrin (78 kDa) and facile isotopic resolution of monoclonal antibody under a variety of acquisition parameters (e.g., 6 s time-domains with absorption mode processing yielded resolution of approximately 1 M at m/z = 2700).

  3. 21 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Greatly Expands Mass Spectrometry Toolbox

    SciTech Connect

    Shaw, Jared B.; Lin, Tzu-Yung; Leach, Franklin E.; Tolmachev, Aleksey V.; Tolić, Nikola; Robinson, Errol W.; Koppenaal, David W.; Paša-Tolić, Ljiljana

    2016-10-12

    We provide the initial performance evaluation of a 21 Tesla Fourier transform ion cyclotron resonance mass spectrometer operating at the Environmental Molecular Sciences Laboratory at Pacific Northwest National Laboratory. The spectrometer constructed for the 21T system employs a commercial dual linear ion trap mass spectrometer coupled to a FTICR spectrometer designed and built in-house. Performance gains from moving to higher magnetic field strength are exemplified by the measurement of peptide isotopic fine structure, complex natural organic matter mixtures, and large proteins. Accurate determination of isotopic fine structure was demonstrated for doubly charged substance P with minimal spectral averaging, and 8,158 molecular formulas assigned to Suwannee River Fulvic Acid standard with RMS error of 10 ppb. We also demonstrated superior performance for intact proteins; namely, broadband isotopic resolution of the entire charge state distribution of apotransferrin (78 kDa) and facile isotopic resolution of monoclonal antibody under a variety of acquisition parameters (e.g. 6 s time-domains with absorption mode processing yielded resolution of approximately 1M at m/z =2,700).

  4. Resonance ionization of rubidium in an ion trap mass spectrometer

    SciTech Connect

    Whitten, W.B.; Ramsey, J.M.; Goeringer, D.E.; Buckley, B.T.

    1990-01-01

    We have recently initiated a study of resonance ionization processes in a quadrupole ion storage trap. The trap is a commercially available Ion Trap Detector that uses the voltage dependence of ion mass instability to obtain a mass spectrum of the trapped ions. We have modified the trap to permit laser excitation of atomic and molecular species within the quadrupole electrodes. Mass resolved resonance ionization spectra have been obtained for NO and Rb, described below. Rb was selected for this study for a number of reasons. We want to explore the potential of the ion trap for high resolution (Doppler free) resonance ionization spectroscopy with CW laser excitation. Rb can be excited to upper Rydberg levels with a series of transitions that can be induced with commercially available semiconductor diode lasers. In addition, levels in the same energy range can be reached through two-photon processes with visible wavelength tunable dye lasers or with single-photon processes after the laser is frequency doubled. The upper Rydberg levels can be ionized by photons, electric field, or collisions. Collisional ionization of a reservoir of Rydberg atoms may be a sensitive scheme for detecting electronegative species. RB has two stable isotopes with nonzero nuclear spin so that isotopic and hyperfine splittings can be used to assess the spectral resolution that is attained.

  5. Compact Ion and Neutral Mass Spectrometer with Ion Drifts, Temperatures and Neutral Winds

    NASA Astrophysics Data System (ADS)

    Paschalidis, Nikolaos

    2016-07-01

    In situ measurements of atmospheric neutral and ion composition and density, temperatures, ion drifts and neutral winds, are in high demand to study the dynamics of the ionosphere-theremosphere-mesosphere system. This paper presents a compact Ion and Neutral Mass Spectrometer (INMS) with impended ion drifts and temperature, and neutral winds capability for in situ measurements of ions and neutrals H, He, N, O, N2, O2. The mass resolution M/dM is approximately 10 at an incoming energy range of 0-20eV. The goal is to resolve ion drifts in the range 0 to 3000m/sec with a resolution better than 50m/sec, and neutral winds in the range of 0 to 1000m/sec with similar resolution. For temperatures the goal is to cover a dynamic range of 0 to 5000K. The INMS is based on front end optics for ions and neutrals, pre acceleration, gated time of flight, top hat ESA, MCP detectors and compact electronics. The instrument is redundant for ions and neutrals with the ion and neutral sensor heads on opposite sides and with full electronics in the middle. The ion front end includes RPA for temperature scanning and neutral front end includes angular modulation and thermionic ionization and ion blocking grids. The electronics include fast electric gating, TOF electronics, TOF binning and C&DH digital electronics. The data package includes 400 mass bins each for ions and neutrals and key housekeeping data for instrument health and calibration. The data sampling can be commanded from 0.1 to 10 sec with 1sec nominal setting. The instrument has significant onboard storage capability and a data compression scheme. The mass spectrometer version of the instrument has been flown on the Exocube mission. The instrument occupied 1.5U volume, weighed only 560 g and required nominal power of 1.6W The ExoCube mission was designed to acquire global knowledge of in-situ densities of [H], [He], [O] and H+, He+, O+ in the upper ionosphere and lower exosphere in combination with incoherent scatter radar and

  6. A compact time-of-flight mass spectrometer for ion source characterization

    SciTech Connect

    Chen, L. Wan, X.; Jin, D. Z.; Tan, X. H.; Huang, Z. X.; Tan, G. B.

    2015-03-15

    A compact time-of-flight mass spectrometer with overall dimension of about 413 × 250 × 414 mm based on orthogonal injection and angle reflection has been developed for ion source characterization. Configuration and principle of the time-of-flight mass spectrometer are introduced in this paper. The mass resolution is optimized to be about 1690 (FWHM), and the ion energy detection range is tested to be between about 3 and 163 eV with the help of electron impact ion source. High mass resolution and compact configuration make this spectrometer useful to provide a valuable diagnostic for ion spectra fundamental research and study the mass to charge composition of plasma with wide range of parameters.

  7. Correlation between y-type ions observed in ion trap and triple quadrupole mass spectrometers.

    PubMed

    Sherwood, Carly A; Eastham, Ashley; Lee, Lik Wee; Risler, Jenni; Vitek, Olga; Martin, Daniel B

    2009-09-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a technique for high-sensitivity targeted analysis. In proteomics, MRM-MS can be used to monitor and quantify a peptide based on the production of expected fragment peaks from the selected peptide precursor ion. The choice of which fragment ions to monitor in order to achieve maximum sensitivity in MRM-MS can potentially be guided by existing MS/MS spectra. However, because the majority of discovery experiments are performed on ion trap platforms, there is concern in the field regarding the generalizability of these spectra to MRM-MS on a triple quadrupole instrument. In light of this concern, many operators perform an optimization step to determine the most intense fragments for a target peptide on a triple quadrupole mass spectrometer. We have addressed this issue by targeting, on a triple quadrupole, the top six y-ion peaks from ion trap-derived consensus library spectra for 258 doubly charged peptides from three different sample sets and quantifying the observed elution curves. This analysis revealed a strong correlation between the y-ion peak rank order and relative intensity across platforms. This suggests that y-type ions obtained from ion trap-based library spectra are well-suited for generating MRM-MS assays for triple quadrupoles and that optimization is not required for each target peptide.

  8. Correlation between y-Type Ions Observed in Ion Trap and Triple Quadrupole Mass Spectrometers

    PubMed Central

    Sherwood, Carly A.; Eastham, Ashley; Lee, Lik Wee; Risler, Jenni; Vitek, Olga; Martin, Daniel B.

    2009-01-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a technique for high-sensitivity targeted analysis. In proteomics, MRM-MS can be used to monitor and quantify a peptide based on the production of expected fragment peaks from the selected peptide precursor ion. The choice of which fragment ions to monitor in order to achieve maximum sensitivity in MRM-MS can potentially be guided by existing MS/MS spectra. However, because the majority of discovery experiments are performed on ion trap platforms, there is concern in the field regarding the generalizability of these spectra to MRM-MS on a triple quadrupole instrument. In light of this concern, many operators perform an optimization step to determine the most intense fragments for a target peptide on a triple quadrupole mass spectrometer. We have addressed this issue by targeting, on a triple quadrupole, the top six y-ion peaks from ion trap-derived consensus library spectra for 258 doubly charged peptides from three different sample sets and quantifying the observed elution curves. This analysis revealed a strong correlation between the y-ion peak rank order and relative intensity across platforms. This suggests that y-type ions obtained from ion trap-based library spectra are well-suited for generating MRM-MS assays for triple quadrupoles and that optimization is not required for each target peptide. PMID:19603825

  9. Highly sensitive solids mass spectrometer uses inert-gas ion source

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Mass spectrometer provides a recorded analysis of solid material surfaces and bulk. A beam of high-energy inert-gas ions bombards the surface atoms of a sample and converts a percentage into an ionized vapor. The mass spectrum analyzer separates the vapor ionic constituents by mass-to-charge ratio.

  10. Development and Deployment of Retrofit PolarisQ Ion Trap Mass Spectrometer for Isotope Ratio Measurements

    SciTech Connect

    Thompson, Cyril V.; Whitten, William B.

    2015-11-01

    This report describes Oak Ridge National Laboratory’s (ORNL) FY15 progress in support of National Nuclear Security Administration’s (NNSA) Portable Mass Spectrometer project. A retrofit PolarisQ ion trap mass spectrometer (RPMS) has been assembled from components of two PolarisQ ion trap mass spectrometers used in previous isotope ratio programs. The retrofit mass spectrometer includes a custom Hastelloy vacuum chamber which is about ¼ the size of the standard aluminum vacuum chamber and reduces the instrument weight from the original by nine pounds. In addition, the new vacuum chamber can be independently heated to reduce impurities such as water, which reacts with UF6 to produce HF in the vacuum chamber. The analyzer and all components requiring service are mounted on the chamber lid, facilitating quick and easy replacement of consumable components such as the filament and electron multiplier.

  11. Method for selective detection of explosives in mass spectrometer or ion mobility spectrometer at parts-per-quadrillion level

    SciTech Connect

    Ewing, Robert G.; Atkinson, David A.; Clowers, Brian H.

    2015-09-01

    A method for selective detection of volatile and non-volatile explosives in a mass spectrometer or ion mobility spectrometer at a parts-per-quadrillion level without preconcentration is disclosed. The method comprises the steps of ionizing a carrier gas with an ionization source to form reactant ions or reactant adduct ions comprising nitrate ions (NO.sub.3.sup.-); selectively reacting the reactant ions or reactant adduct ions with at least one volatile or non-volatile explosive analyte at a carrier gas pressure of at least about 100 Ton in a reaction region disposed between the ionization source and an ion detector, the reaction region having a length which provides a residence time (tr) for reactant ions therein of at least about 0.10 seconds, wherein the selective reaction yields product ions comprising reactant ions or reactant adduct ions that are selectively bound to the at least one explosive analyte when present therein; and detecting product ions with the ion detector to determine presence or absence of the at least one explosive analyte.

  12. The role of fiber optics in mass spectrometer electro-optical ion detection

    NASA Technical Reports Server (NTRS)

    Norris, D. D.; Giffin, C. E.

    1976-01-01

    This paper describes the development of an electro-optical ion detector combining the best features of photographic and electrical ion detection (i.e., wide mass range coverage and low ion detection threshold respectively). A nineteen fold fiber optic image dissector is discussed which reformats the 1 mm x 361 mm mass spectrometer focal plane format to a 19 mm x 19 mm format suitable for vidicon imaging and electronic display of the data.

  13. A feasibility study of ion implantation techniques for mass spectrometer calibration

    NASA Technical Reports Server (NTRS)

    Koslin, M. E.; Krycuk, G. A.; Schatz, J. G., Jr.; White, F. A.; Wood, G. M.

    1978-01-01

    An experimental study was undertaken to examine the feasibility of using ion-implanted filaments doped with either an alkali metal or noble gas for in situ recalibration of onboard mass spectrometers during extended space missions. Implants of rubidium and krypton in rhenium ribbon filaments were subsequently tested in a bakeable 60 deg sector mass spectrometer operating in the static mode. Surface ionization and electron impact ion sources were both used, each yielding satisfactory results. The metallic implant with subsequent ionization provided a means of mass scale calibration and determination of system operating parameters, whereas the noble gas thermally desorbed into the system was more suited for partial pressure and sensitivity determinations.

  14. High precision electric gate for time-of-flight ion mass spectrometers

    NASA Technical Reports Server (NTRS)

    Sittler, Edward C. (Inventor)

    2011-01-01

    A time-of-flight mass spectrometer having a chamber with electrodes to generate an electric field in the chamber and electric gating for allowing ions with a predetermined mass and velocity into the electric field. The design uses a row of very thin parallel aligned wires that are pulsed in sequence so the ion can pass through the gap of two parallel plates, which are biased to prevent passage of the ion. This design by itself can provide a high mass resolution capability and a very precise start pulse for an ion mass spectrometer. Furthermore, the ion will only pass through the chamber if it is within a wire diameter of the first wire when it is pulsed and has the right speed so it is near all other wires when they are pulsed.

  15. Final Report - Ion Production and Transport in Atmospheric Pressure Ion Source Mass Spectrometers

    SciTech Connect

    Farnsworth, Paul B.; Spencer, Ross L.

    2014-05-14

    This document is the final report on a project that focused in the general theme of atmospheric-pressure ion production and transport for mass spectrometry. Within that general theme there were two main projects: the fundamental study of the transport of elemental ions through the vacuum interface of an inductively coupled plasma mass spectrometer (ICPMS), and fundamental studies of the ionization mechanisms in ambient desorption/ionization (ADI) sources for molecular mass spectrometry. In both cases the goal was to generate fundamental understanding of key instrumental processes that would lead to the development of instruments that were more sensitive and more consistent in their performance. The emphasis on consistency derives from the need for instruments that have the same sensitivity, regardless of sample type. In the jargon of analytical chemistry, such instruments are said to be free from matrix effects. In the ICPMS work each stage of ion production and of ion transport from the atmospheric pressure to the high-vacuum mass analyzer was studied. Factors controlling ion transport efficiency and consistency were identified at each stage of pressure reduction. In the ADI work the interactions between an electrospray plume and a fluorescent sample on a surface were examined microscopically. A new mechanism for analyte ion production in desorption electrospray ionization (DESI) was proposed. Optical spectroscopy was used to track the production of reactive species in plasmas used as ADI sources. Experiments with mixed-gas plasmas demonstrated that the addition of a small amount of hydrogen to a helium ADI plasma could boost the sensitivity for some analytes by over an order of magnitude.

  16. Performance Evaluation of a Dual Linear Ion Trap-Fourier Transform Ion Cyclotron Resonance Mass Spectrometer for Proteomics Research

    PubMed Central

    Weisbrod, Chad R.; Hoopmann, Michael R.; Senko, Michael W.; Bruce, James E.

    2014-01-01

    A novel dual cell linear ion trap Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) and its performance characteristics are reported. A linear ion trap-Fourier transform ion cyclotron resonance mass spectrometer has been modified to incorporate a LTQ-Velos mass spectrometer. This modified instrument features efficient ion accumulation and fast MS/MS acquisition capabilities of dual cell linear RF ion trap instruments coupled to the high mass accuracy, resolution, and dynamic range of a FT-ICR for improved proteomic coverage. The ion accumulation efficiency is demonstrated to be an order of magnitude greater than that observed with LTQ-FT Ultra instrumentation. The proteome coverage with yeast was shown to increase over the previous instrument generation by 50% (100% increase on the peptide level). In addition, many lower abundance level yeast proteins were only detected with this modified instrument. This novel configuration also enables beam type CID fragmentation using a dual cell RF ion trap mass spectrometer. This technique involves accelerating ions between traps while applying an elevated DC offset to one of the traps to accelerate ions and induce fragmentation. This instrument design may serve as a useful option for labs currently considering purchasing new instrumentation or upgrading existing instruments. PMID:23590889

  17. Method for studying a sample of material using a heavy ion induced mass spectrometer source

    DOEpatents

    Fries, D.P.; Browning, J.F.

    1999-02-16

    A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu. 3 figs.

  18. Method for studying a sample of material using a heavy ion induced mass spectrometer source

    DOEpatents

    Fries, David P.; Browning, James F.

    1999-01-01

    A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

  19. System for studying a sample of material using a heavy ion induced mass spectrometer source

    DOEpatents

    Fries, David P.; Browning, James F.

    1998-01-01

    A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

  20. System for studying a sample of material using a heavy ion induced mass spectrometer source

    DOEpatents

    Fries, D.P.; Browning, J.F.

    1998-07-21

    A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high (n,f) reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu. 3 figs.

  1. Fundamental studies of ion injection and trapping of electrosprayed ions on a quadrupole ion trap mass spectrometer

    NASA Astrophysics Data System (ADS)

    Quarmby, Scott Thomas

    The quadrupole ion trap is a highly versatile and sensitive analytical mass spectrometer. Because of the advantages offered by the ion trap, there has been intense interest in coupling it to ionization techniques such as electrospray which form ions externally to the ion trap. In this work, experiments and computer simulations were employed to study the injection of electrosprayed ions into the ion trap of a Finnigan MAT LCQ LC/MS n mass spectrometer. The kinetic energy distribution of the ion beam was characterized and found to be relatively wide, a result of the high pressures from the atmospheric pressure source. One of the most important experimental parameters which affects ion injection efficiency is the RF voltage applied to the ring electrode. A theoretical model was fit to experimental data allowing the optimum RF voltage for trapping a given m/z ion to be predicted. Computer simulations of ion motion were performed to study the effect of various instrumental parameters on trapping efficiency. A commercially available ion optics program, SIMION v6.0, was chosen because it allowed the actual ion trap electrode geometry including endcap holes to be simulated. In contrast to previous computer simulations, SIMION provided the ability to start ions outside the ion trap and to simulate more accurately the injection of externally formed ions. The endcap holes were found to allow the RF field to penetrate out of the ion trap and affect ions as they approached the ion trap. From these simulations, a model for the process by which injected ions are trapped was developed. Using these computer simulations, techniques of improving trapping efficiency were investigated. Most previous techniques perturb ions which are already in the ion trap and therefore cannot be used to accumulate ions; the ability to accumulate ions is a necessity with ionization sources such as electrospray which form ions continuously. One such novel technique for improving trapping efficiency

  2. Development and Evaluation of a Variable-Temperature Quadrupole Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Derkits, David; Wiseman, Alex; Snead, Russell F.; Dows, Martina; Harge, Jasmine; Lamp, Jared A.; Gronert, Scott

    2016-02-01

    A new, variable-temperature mass spectrometer system is described. By applying polyimide heating tape to the end-cap electrodes of a Bruker (Bremen, Germany) Esquire ion trap, it is possible to vary the effective temperature of the system between 40 and 100°C. The modification does not impact the operation of the ion trap and the heater can be used for extended periods without degradation of the system. The accuracy of the ion trap temperatures was assessed by examining two gas-phase equilibrium processes with known thermochemistry. In each case, the variable-temperature ion trap provided data that were in good accord with literature data, indicating the effective temperature in the ion trap environment was being successfully modulated by the changes in the set-point temperatures on the end-cap electrodes. The new design offers a convenient and effective way to convert commercial ion trap mass spectrometers into variable-temperature instruments.

  3. A Rocket-borne Ion Mass Spectrometer for the Mesosphere That is Pumped by Rocket Aerodynamics

    NASA Astrophysics Data System (ADS)

    Smith, S.; Robertson, S.; Sternovsky, Z.

    2007-12-01

    Rocket-borne mass spectrometers for ions have been flown that were evacuated by cryogenic vacuum pumps with liquid helium or neon. There have not been flights since 1993 because these instruments required expensive deliveries of cryogens and frequent refillings. Advances in (1) aerodynamic modeling, (2) mass spectrometer design, and (3) ion detection technology make possible a new approach to mass spectrometry in the mesosphere in which the spectrometer is pumped by the flow around the rocket. First, the Direct Simulation Monte-Carlo method has been applied to simulating the air flow around the rocket payload. We find that if the forward deck of the payload is supported on a stalk of smaller diameter (10 cm for example), that a low-density void is created below the forward deck by the flow around the payload, assuming that the payload is pointed in the ram direction. The air density below the deck is reduced from ambient by a factor 7 and 15 at altitudes of 80 and 90 km, respectively. The mass spectrometer is exhausted into this void which acts as a pump. In a conservative scenario, the spectrometer is kept evacuated on the upleg then opened at the apogee both at the inlet and exit. Data are acquired on the downleg to 70 km, below which the pressure in the low-density void becomes too high. Second, we use the rotating field mass spectrometer which operates at higher pressure (up to 30 mTorr) than the quadrupole spectrometer because the ion path length is shorter (2 cm) and because a larger ion acceleration potential is used that reduces the ion-neutral collision cross section. Third, we use a new design of channel electron multiplier that has been shown to operate at pressures up to 10 mTorr in the lab, corresponding to the number density at approximately 80 km in the arctic winter.

  4. Instrument manual for the retarding ion mass spectrometer on Dynamics Explorer-1

    NASA Technical Reports Server (NTRS)

    Fields, S. A.; Baugher, C. R.; Chappell, C. R.; Reasoner, D. L.; Hammack, H. D.; Wright, W. W.; Hoffman, J. H.

    1982-01-01

    The retarding ion mass spectrometer (RIMS) for Dynamics Explorer-1 is an instrument designed to measure the details of the thermal plasma distribution. It combines the ion temperature determining capability of the retarding potential analyzer with the compositional capabilities of the mass spectrometer and adds multiple sensor heads to sample all directions relative to the spacecraft ram direction. This manual provides a functional description of the RIMS, the instrument calibration, and a description of the commands which can be stored in the instrument logic to control its operation.

  5. Design and performance of an electrospray ion source for magnetic-sector mass spectrometers

    NASA Astrophysics Data System (ADS)

    Belov, Mikhail E.; Colburn, Alex W.; Derrick, Peter J.

    1998-03-01

    An electrospray ion (ESI) source capable of operating at accelerating potentials of up to 11 kV has been designed and fabricated. The ESI source has been shown to deliver ion beams with a total current up to 20 pA and an emittance of 2-3 mm mrad in analysis of the peptide gramicidin S (molecular mass 1140.7 Da) and the protein bovine insulin B chain (molecular mass 3495.9 Da). Coupled to a two-sector tandem mass spectrometer, the ESI source produced efficiently the multiply charged ions of proteins, such as bovine ubiquitin (molecular mass 8564.8 Da) and cytochrome c (molecular mass 12327 Da). The high ion currents and high kinetic energies of the electrospray ions (up to 200 keV) characterize this ESI source as a powerful tool to be used in structural analysis of macromolecules by collision-induced dissociation.

  6. Electron capture dissociation in a digital ion trap mass spectrometer.

    PubMed

    Ding, Li; Brancia, Francesco L

    2006-03-15

    Electron capture dissociation was implemented in a digital ion trap without using any magnetic field to focus the electrons. Since rectangular waveforms are employed in the DIT for both trapping and dipole excitation, electrons can be injected into the trap when the electric field is constant. Following deceleration, electrons reach the precursor ion cloud. The fragment ions produced by interactions with the electron beam are subsequently analyzed by resonant ejection. [Glu(1)]-Fibrinopeptide B and substance P were used to evaluate the performance of the current design. Fragmentation efficiency of 5.5% was observed for substance P peptide ions. Additionally, analysis of the monophosphorylated peptide FQ[pS]EEQQQTEDELQDK shows that in the resulting c- and z-type ions, the phosphate group is retained on the phophoserine residue, providing information on which amino acid residue the modification is located.

  7. The effects of analyte mass and collision gases on ion beam formation in an inductively coupled plasma mass spectrometer

    NASA Astrophysics Data System (ADS)

    Larsen, Jessica J.; Edmund, Alisa J.; Farnsworth, Paul B.

    2016-11-01

    Planar laser induced fluorescence (PLIF) was used to evaluate the effect of matrix components on the formation and focusing of a Ba ion beam in a commercial inductively coupled plasma mass spectrometer. Cross sections of the ion beams were taken in the second vacuum stage, in front of the entrance to the mass analyzer. Under normal operating conditions, the addition of Pb shifted the position of the Ba ion beam to the right. PLIF was also used to evaluate the effect of a collision reaction interface (CRI) on Ca and Ba ion beams. A wider velocity distribution of ions and a decrease in overall intensity were observed for the CRI images. The fluorescence and mass spectrometer signals decreased with increased CRI flow rates. These effects were most obvious for Ca ions with He gas.

  8. Comet encke: meteor metallic ion identification by mass spectrometer.

    PubMed

    Goldberg, R A; Aikin, A C

    1973-04-20

    Metal ions including 23(+) (Na(+)), 24(+) (Mg(+)) 28(+) (Si(+)), 39(+) (K(+)), 40(+) (Ca(+)), 45(+) (Sc(+)), 52(+) Cr(+)). 56(+) (Fe(+)), and 58(+) (Ni(+)) have been detected in the upper atmosphere during the period of the Beta Taurids meteor shower. The abundances of these ions relative to Si(+) show, agreement in most instances with abundances in chondrites. A notable exception is 45(+), which, if it is Sc(+), is 100 times more abundant than neutral scandium found in chondrites.

  9. Comet Encke: Meteor metallic ion identification by mass spectrometer

    NASA Technical Reports Server (NTRS)

    Goldberg, R. A.; Aikin, A. C.

    1972-01-01

    Metal ions including Na-40(+), Mg-24(+), Si-28(+), K-39(+), Ca-40(+), Sc-45(+), Cr-52(+), Fe-56(+), and Ni-58(+) were detected in the upper atmosphere during the beta Taurids meteor shower. Abundances of these ions relative to Si(+) show agreement in most instances with chondrites. A notable exception is 45(+), which is Sc(+), is 100 times more abundant than neutral scandium found in chondrites.

  10. Infrared multiphoton dissociation of peptide cations in a dual pressure linear ion trap mass spectrometer.

    PubMed

    Gardner, Myles W; Smith, Suncerae I; Ledvina, Aaron R; Madsen, James A; Coon, Joshua J; Schwartz, Jae C; Stafford, George C; Brodbelt, Jennifer S

    2009-10-01

    A dual pressure linear ion trap mass spectrometer was modified to permit infrared multiphoton dissociation (IRMPD) in each of the two cells-the first a high pressure cell operated at nominally 5 x 10(-3) Torr and the second a low pressure cell operated at nominally 3 x 10(-4) Torr. When IRMPD was performed in the high pressure cell, most peptide ions did not undergo significant photodissociation; however, in the low pressure cell peptide cations were efficiently dissociated with less than 25 ms of IR irradiation regardless of charge state. IRMPD of peptide cations allowed the detection of low m/z product ions including the y(1) fragments and immonium ions which are not typically observed by ion trap collision induced dissociation (CID). Photodissociation efficiencies of approximately 100% and MS/MS (tandem mass spectrometry) efficiencies of greater than 60% were observed for both multiply and singly protonated peptides. In general, higher sequence coverage of peptides was obtained using IRMPD over CID. Further, greater than 90% of the product ion current in the IRMPD mass spectra of doubly charged peptide ions was composed of singly charged product ions compared to the CID mass spectra in which the abundances of the multiply and singly charged product ions were equally divided. Highly charged primary product ions also underwent efficient photodissociation to yield singly charged secondary product ions, thus simplifying the IRMPD product ion mass spectra.

  11. Infrared Multiphoton Dissociation of Peptide Cations in a Dual Pressure Linear Ion Trap Mass Spectrometer

    PubMed Central

    Gardner, Myles W.; Smith, Suncerae I.; Ledvina, Aaron R.; Madsen, James A.; Coon, Joshua J.; Schwartz, Jae C.; Stafford, George C.; Brodbelt, Jennifer S.

    2009-01-01

    A dual pressure linear ion trap mass spectrometer was modified to permit infrared multiphoton dissociation (IRMPD) in each of the two cells - the first a high pressure cell operated at nominally 5 × 10-3 Torr and the second a low pressure cell operated at nominally 3 × 10-4 Torr. When IRMPD was performed in the high pressure cell, most peptide ions did not undergo significant photodissociation; however, in the low pressure cell peptide cations were efficiently dissociated with less than 25 ms of IR irradiation regardless of charge state. IRMPD of peptide cations allowed the detection of low m/z product ions including the y1 fragments and immonium ions which are not typically observed by ion trap collision induced dissociation (CID). Photodissociation efficiencies of ~100% and MS/MS (tandem mass spectrometry) efficiencies of greater than 60% were observed for both multiply and singly protonated peptides. In general, higher sequence coverage of peptides was obtained using IRMPD over CID. Further, greater than 90% of the product ion current in the IRMPD mass spectra of doubly charged peptide ions was composed of singly charged product ions compared to the CID mass spectra in which the abundances of the multiply and singly charged product ions were equally divided. Highly charged primary product ions also underwent efficient photodissociation to yield singly charged secondary product ions, thus simplifying the IRMPD product ion mass spectra. PMID:19739654

  12. Design of An Improved Miniature Ion Neutral Mass Spectrometer for NASA Applications

    NASA Technical Reports Server (NTRS)

    Swaminathan, Viji K.; Alig, Roger C.

    1997-01-01

    The ion optics of NASA's Ion Neutral Mass Spectrometer (INMS) sensor was simulated with three dimensional models of the open source, the quadrupole deflector, the exit lens system and the quadrupole mass analyzer to design more compact models with lower weight. Comparison of calculated transmission with experimental results shows good agreement. Transmission analyses with varying geometrical parameters and voltages throw light on possible ways of reducing the size of the sensor. Trajectories of ions of mass 1-99 amu were simulated to analyze and optimize transmission. Analysis of open source transmission with varying angle of attack shows that the angular acceptance can be considerably increased by programming the voltages on the ion trap/ collimator. Analysis of transmission sensitivity to voltages and misalignments of the quadrupole deflector rods indicate that increased transmission is possible with a geometrically asymmetrical deflector and a deflector can be designed with much lower sensitivities of transmission. Bringing the disks closer together can decrease the size of the quadrupole deflector and also increase transmission. The exit lens system can be redesigned to be smaller by eliminating at least one electrode entirely without loss of transmission. Ceramic materials were investigated to find suitable candidates for use in the construction of lighter weight mass spectrometer. A high-sensitivity, high-resolution portable gas chromatograph mass spectrometer with a mass range of 2-700 amu has been built and will be commercialized in Phase 3.

  13. A novel aircraft-based tandem mass spectrometer for atmospheric ion and trace gas measurements

    NASA Astrophysics Data System (ADS)

    Moehler, O.; Reiner, Th.; Arnold, F.

    1993-05-01

    The general design and operation of a novel aircraft-based triple-quadrupole mass spectrometer (TQMS) developed for the improved detection and collisional analysis of atmospheric ions and trace gases are described. The instrument is also suitable for laboratory collision-induced dissociation measurements, studies of ion-molecule reactions, and analytical applications. Highly sensitive and selective trace gas detection by chemical ionization mass spectrometry is also possible using a novel ion injection technique. Result of aircraft-based measurements made with the TQMS are summarized.

  14. Design and construction of a nanoelectrospray ion source for a triple quadrupole mass spectrometer

    NASA Astrophysics Data System (ADS)

    Troxler, Heinz; Wetzel, Erich; Kuster, Thomas; Heizmann, Claus W.

    1999-05-01

    The design and construction of a nanoelectrospray ion source for a triple quadrupole mass spectrometer that is used for identification and analysis of minimum peptide amounts is described. This interface exhibits several improvements over commercially available devices: a new capillary holder that allows very simple loading and placement of the spray capillary, and a rotary stage that enables reproducible adjustment of the capillary's angle at the orifice of the mass spectrometer. We also introduced a pressure-regulating system for fast and reproducible adjustment of the static backing air pressure onto the sample solution in the spray capillary. Furthermore, an electric safety circuit increases handling and operation safety of the nanoelectrospray interface.

  15. Advanced Ion Mass Spectrometer for Giant Planet Ionosphere, Magnetospheres and Moons

    NASA Astrophysics Data System (ADS)

    Sittler, Edward; Cooper, John; Paschalidis, Nick; Jones, Sarah; Brinkerhoff, William; Paterson, William; Ali, Ashraf; Coplan, Michael; Chornay, Dennis; Sturner, Steve; Benna, Mehdi; Bateman, Fred; Fontaine, Dominique; Verdeil, Christophe; Andre, Nicolas; Blanc, Michel; Wurz, Peter

    2017-01-01

    We present our Advanced Ion Mass Spectrometer (AIMS) for outer planet missions which has been under development from various NASA sources (NASA Living with a Star Instrument Development (LWSID), NASA Astrobiology Instrument Development (ASTID), NASA Goddard Internal Research and Development (IRAD)s) to measure elemental, isotopic, and simple molecular composition abundances of 1 V to 25 kV hot ions with wide field-of-view (FOV) in the 1 - 60 amu mass range at mass resolution M/ ΔM <= 60 over a wide dynamic range of particle intensities and penetrating radiation background from the inner magnetospheres of Jupiter and Saturn to the outer magnetospheric boundary regions and the upstream solar wind. This instrument will work for both spinning spacecraft and 3-axis stabilized spacecraft. AIMS will measure the ion velocity distribution functions (VDF) for the individual ion species from which velocity moments will give their ion density, flow velocity and temperature.

  16. Flowing gas in mass spectrometer: method for characterization and impact on ion processing.

    PubMed

    Zhou, Xiaoyu; Ouyang, Zheng

    2014-10-21

    Mass spectrometers are complex instrumentation systems where ions are transferred though different pressure regions and mass-analyzed under high vacuum. In this work, we have investigated the impact of the gas flows that exit almost universally in all pressure regions. We developed a method that incorporates the dynamic gas field with the electric field in the simulation of ion trajectories. The scope of the electro-hydrodynamic simulation (EHS) method was demonstrated for characterizing the ion optical systems at atmospheric pressure interfaces. With experimental validation, the trapping of the externally injected ions in a linear ion trap at low pressure was also studied. Further development of the EHS method and the knowledge acquired in this research are expected to be useful in the design of hybrid instruments and the study of ion energetics.

  17. Flowing Gas in Mass Spectrometer: Method for Characterization and Impact on Ion Processing

    PubMed Central

    Zhou, Xiaoyu; Ouyang, Zheng

    2014-01-01

    Mass spectrometers are complex instrumentation systems with ions transferred though different pressure regions and mass analyzed at high vacuum. In this work, we have investigated the impacts of the gas flows that exit almost universally in all pressure regions and developed a method incorporating the dynamic gas field with the electric (E) field in the simulation of ion trajectories. The capability of the electro-hydrodynamic simulation (EHS) method was demonstrated for characterizing the ion optical systems in atmospheric pressure interfaces. With experimental validation, the trapping of the externally-injected ions in a linear ion trap at low pressure has also been studied. Further development of the EHS method and the knowledge acquired in this research are expected to be useful in the design of hybrid instruments and study of ion energetics. PMID:25121805

  18. Infrared ion spectroscopy in a modified quadrupole ion trap mass spectrometer at the FELIX free electron laser laboratory

    NASA Astrophysics Data System (ADS)

    Martens, Jonathan; Berden, Giel; Gebhardt, Christoph R.; Oomens, Jos

    2016-10-01

    We report on modifications made to a Paul-type quadrupole ion trap mass spectrometer and discuss its application in infrared ion spectroscopy experiments. Main modifications involve optical access to the trapped ions and hardware and software coupling to a variety of infrared laser sources at the FELIX infrared free electron laser laboratory. In comparison to previously described infrared ion spectroscopy experiments at the FELIX laboratory, we find significant improvements in efficiency and sensitivity. Effects of the trapping conditions of the ions on the IR multiple photon dissociation spectra are explored. Enhanced photo-dissociation is found at lower pressures in the ion trap. Spectra obtained under reduced pressure conditions are found to more closely mimic those obtained in the high-vacuum conditions of an Fourier transform ion cyclotron resonance mass spectrometer. A gas-mixing system is described enabling the controlled addition of a secondary gas into helium buffer gas flowing into the trap and allows for ion/molecule reactions in the trap. The electron transfer dissociation (ETD) option of the mass spectrometer allows for IR structure characterization of ETD-generated peptide dissociation products.

  19. Development of a novel mass spectrometer equipped with an electron cyclotron resonance ion source.

    PubMed

    Kidera, Masanori; Takahashi, Kazuya; Enomoto, Shuichi; Mitsubori, Youhei; Goto, Akira; Yano, Yasushige

    2007-01-01

    The ionization efficiency of an electron cyclotron resonance ion source (ECRIS) is generally high, and all elements can be fundamentally ionized by the high-temperature plasma. We focused our attention on the high potentiality of ECRIS as an ion source for mass spectrometers and attempted to customize the mass spectrometer equipped with an ECRIS. Precise measurements were performed by using an ECRIS that was specialized and customized for elemental analysis. By using the charge-state distribution and the isotope ratio, the problem of overlap such as that observed in the spectra of isobars could be solved without any significant improvement in the mass resolution. When the isotope anomaly (or serious mass discrimination effect) was not observed in ECR plasma, the system was found to be very effective for isotope analysis. In this paper, based on the spectrum (ion current as a function of an analyzing magnet current) results of low charged state distributions (2+, 3+, 4+, ...) of noble gases, we discuss the feasibility of an elemental analysis system employing an ECRIS, particularly for isotopic analysis. The high-performance isotopic analysis obtained for ECRIS mass spectrometer in this study suggests that it can be widely applied to several fields of scientific study that require elemental or isotopic analyses with high sensitivity.

  20. Giotto ion mass spectrometer measurements at comet P/Grigg-Skjellerup

    NASA Technical Reports Server (NTRS)

    Goldstein, R.; Altwegg, K.; Fuselier, S. A.; Goldstein, B. E.; Balsiger, H.; Jost, F.; Coates, A.; Neubauer, F. M.; Rosenbauer, H.

    1994-01-01

    The Giotto ion mass spectrometer high-intensity spectrometer (IMS-HIS) measured fluxes of ions from about 260,000 km before (1008:37 UT spacecraft time) to about 86,000 km after (1701:33 UT spacecraft time) closest approach to comet P/Grigg-Skjellerup during the encounter on July 10, 1992. Although the HIS sensor was not designed to measure protons, these ions were measured far from the comet. Close in to the comet, the ions observed were probably also protons, although heavier ions cannot be completely ruled out. Considerable temporal structure appears in the data, well-correlated with the data of other instruments onboard, especially those of the magnetometer. In particular, the ion count rate correlates with the direction of the magnetic field. This strong modulation at the water group ion cyclotron period (approx. 90 s) inside the inbound bow wave indicates a very narrow ion pitch angle distribution. Hence at Grigg-Skjellerup the ions appear to experience very little pitch angle scattering. This may result from strong compression in the rapidly increasing magnetic field.

  1. Super-Atmospheric Pressure Ion Sources: Application and Coupling to API Mass Spectrometer.

    PubMed

    Chen, Lee Chuin; Rahman, Md Matiur; Hiraoka, Kenzo

    2014-01-01

    Pressurizing the ionization source to gas pressure greater than atmospheric pressure is a new tactic aimed at further improving the performance of atmospheric pressure ionization (API) sources. In principle, all API sources, such as ESI, APCI and AP-MALDI, can be operated at pressure higher than 1 atm if suitable vacuum interface is available. The gas pressure in the ion source can have different role for different ionization. For example, in the case of ESI, stable electrospray could be sustained for high surface tension liquid (e.g., pure water) under super-atmospheric pressure, owing to the absence of electric discharge. Even for nanoESI, which is known to work well with aqueous solution, its stability and sensitivity were found to be enhanced, particularly in the negative mode when the ion source was pressurized. For the gas phase ionization like APCI, measurement of gaseous compound also showed an increase in ion intensity with the ion source pressure until an optimum pressure at around 4-5 atm. The enhancement was due to the increased collision frequency among reactant ion and analyte that promoted the ion/molecule reaction and a higher intake rate of gas to the mass spectrometer. Because the design of vacuum interface for API instrument is based on the upstream pressure of 1 atm, some coupling aspects need to be considered when connecting the high pressure ion source to the mass spectrometer. Several coupling strategies are discussed in this paper.

  2. Control and Data Transmission System for a Balloon-Borne Ion Mass Spectrometer,

    DTIC Science & Technology

    1980-10-01

    BALLOON-4ORNE ON .MASSSPECTROMETER. - . Raimundas / SukY l(- J, Spencer IRochefort Northeastern University Electronics Research W6ratory Boston...ONG REPORT ,MR 1. AUlpORj.) CLir6ACT OR. GRN UNS! RV R. SUKYS F19628-78-C-021 8 0.5. ROCHEFORT VP:REORMING ONG ANIZAIIOM NPIME AND ADDRESS " PAOGNAm Et...FOR A BALLOON-BORNE ION MASS SPECTROMETER Raimundas Sukys and J. Spencer Rochefort Department of Electrical Engineering / Northeastern University

  3. Mass Spectrometers in Space!

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, William B.

    2012-01-01

    Exploration of our solar system over several decades has benefitted greatly from the sensitive chemical analyses offered by spaceflight mass spectrometers. When dealing with an unknown environment, the broadband detection capabilities of mass analyzers have proven extremely valuable in determining the composition and thereby the basic nature of space environments, including the outer reaches of Earth s atmosphere, interplanetary space, the Moon, and the planets and their satellites. Numerous mass analyzer types, including quadrupole, monopole, sector, ion trap, and time-of-flight have been incorporated in flight instruments and delivered robotically to a variety of planetary environments. All such instruments went through a rigorous process of application-specific development, often including significant miniaturization, testing, and qualification for the space environment. Upcoming missions to Mars and opportunities for missions to Venus, Europa, Saturn, Titan, asteroids, and comets provide new challenges for flight mass spectrometers that push to state of the art in fundamental analytical technique. The Sample Analysis at Mars (SAM) investigation on the recently-launch Mars Science Laboratory (MSL) rover mission incorporates a quadrupole analyzer to support direct evolved gas as well as gas chromatograph-based analysis of martian rocks and atmosphere, seeking signs of a past or present habitable environment. A next-generation linear ion trap mass spectrometer, using both electron impact and laser ionization, is being incorporated into the Mars Organic Molecule Analyzer (MOMA) instrument, which will be flown to Mars in 2018. These and other mass spectrometers and mission concepts at various stages of development will be described.

  4. Implementation of electron-transfer dissociation on a hybrid linear ion trap-orbitrap mass spectrometer.

    PubMed

    McAlister, Graeme C; Phanstiel, Doug; Good, David M; Berggren, W Travis; Coon, Joshua J

    2007-05-15

    We describe the adaptation of a hybrid quadrupole linear ion trap-orbitrap mass spectrometer to accommodate electron-transfer ion/ion reactions (ETD) for peptide and protein characterization. The method utilizes pulsed, dual electrospray ion sources and requires minimal instrument modification. Switching between cation and reagent anion injection schemes is automated and accomplished within a few hundred milliseconds. Ion/ion reactions are conducted within the linear ion trap, after which the c- and z-type product ions are passed to the orbitrap for high-resolution m/z analysis. With this arrangement, mass accuracies are typically measured to within 2 ppm at a resolving power of approximately 60 000. Using large peptides and intact proteins, we demonstrate such capabilities will accelerate our ability to interrogate high-mass species. To illustrate compatibility with automated data-dependent analysis and subsequent data processing, we couple the technique with an online chromatographic separation of a yeast whole-cell lysate followed by peptide identification using ProSight PC. Fairly long pulsing times and relatively low ET efficiency, as compared to conventional ETD instrumentation, are the main drawbacks of this approach. Still, our results suggest that the implementation of ETD on sensitive, high-resolution, and high-mass accuracy hybrid instrumentation, such as the orbitrap, will substantially propel the emergent fields of middle- and top-down proteomics.

  5. Following the Ions through a Mass Spectrometer with Atmospheric Pressure Interface: Simulation of Complete Ion Trajectories from Ion Source to Mass Analyzer.

    PubMed

    Zhou, Xiaoyu; Ouyang, Zheng

    2016-07-19

    Ion trajectory simulation is an important and useful tool in instrumentation development for mass spectrometry. Accurate simulation of the ion motion through the mass spectrometer with atmospheric pressure ionization source has been extremely challenging, due to the complexity in gas hydrodynamic flow field across a wide pressure range as well as the computational burden. In this study, we developed a method of generating the gas flow field for an entire mass spectrometer with an atmospheric pressure interface. In combination with the electric force, for the first time simulation of ion trajectories from an atmospheric pressure ion source to a mass analyzer in vacuum has been enabled. A stage-by-stage ion repopulation method has also been implemented for the simulation, which helped to avoid an intolerable computational burden for simulations at high pressure regions while it allowed statistically meaningful results obtained for the mass analyzer. It has been demonstrated to be suitable to identify a joint point for combining the high and low pressure fields solved individually. Experimental characterization has also been done to validate the new method for simulation. Good agreement was obtained between simulated and experimental results for ion transfer though an atmospheric pressure interface with a curtain gas.

  6. Method for calibrating mass spectrometers

    DOEpatents

    Anderson, Gordon A [Benton City, WA; Brands, Michael D [Richland, WA; Bruce, James E [Schwenksville, PA; Pasa-Tolic, Ljiljana [Richland, WA; Smith, Richard D [Richland, WA

    2002-12-24

    A method whereby a mass spectra generated by a mass spectrometer is calibrated by shifting the parameters used by the spectrometer to assign masses to the spectra in a manner which reconciles the signal of ions within the spectra having equal mass but differing charge states, or by reconciling ions having known differences in mass to relative values consistent with those known differences. In this manner, the mass spectrometer is calibrated without the need for standards while allowing the generation of a highly accurate mass spectra by the instrument.

  7. An electrodynamic ion funnel interface for greater sensitivity and higher throughput with linear ion trap mass spectrometers

    NASA Astrophysics Data System (ADS)

    Page, Jason S.; Tang, Keqi; Smith, Richard D.

    2007-09-01

    An electrospray ionization interface incorporating an electrodynamic ion funnel has been designed and implemented on a linear ion trap mass spectrometer (Thermo Electron, LTQ). We found ion transmission to be greatly improved by replacing the standard capillary-skimmer interface with the capillary-ion funnel interface. An infusion study using a serial dilution of a reserpine solution showed that ion injection (accumulation) times to fill the ion trap at a given automatic gain control (AGC) target value were reduced by ~90% which resulted in an ~10-fold increase in peak intensities. In liquid chromatography tandem MS (LC-MS/MS) experiments performed using a global protein digest sample from the bacterium, Shewanella oneidensis, more peptides and proteins were identified when the ion funnel interface was used in place of the standard interface. This improvement was most pronounced at lower sample concentrations, where extended ion accumulation times are required, resulting in an ~2-fold increase in the number of protein identifications. Implementation of the ion funnel interface on a LTQ Fourier transform (FT) mass spectrometer showed a ~25-50% reduction in spectrum acquisition time. The duty cycle improvement in this case was due to the ion accumulation event contributing a larger portion to the total spectrum acquisition time.

  8. Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions

    SciTech Connect

    Gulyuz, Kerim; Stedwell, Corey N.; Wang Da; Polfer, Nick C.

    2011-05-15

    We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

  9. Spiking structure of amplitude characteristics for ion trajectories in hyperboloidal mass spectrometers: the theory.

    PubMed

    Sheretov, Ernst P; Philippov, Igor V; Karnav, Tatiana B; Kolotilin, Boris I; Ivanov, Vladimir W

    2002-01-01

    We present a theory that describes a 'spiking' structure of the amplitude characteristics for trajectories of ions within a hyperboloidal mass spectrometer (HMS) discovered and reported recently. This effect, as well as modulation parametric resonance, relates directly to a fine structure of the stability diagram for a HMS. A method of extremum characteristic solutions of the Hill equation (developed in our laboratory earlier) has been used in this work. Simple expressions determined the shape of narrow dips (or reversed peaks) in the amplitude of ion oscillation versus stability parameter curves and conditions of their appearance are presented. The results that were calculated from analytical expressions are compared with those obtained from direct computations of ion trajectories in a HMS. This effect with respect to a nature of 'black holes' or 'black canyons' observed earlier in investigations of trapping efficiency and ion trapping within ion traps is discussed.

  10. Laserspray ionization on a commercial atmospheric pressure-MALDI mass spectrometer ion source: selecting singly or multiply charged ions.

    PubMed

    McEwen, Charles N; Larsen, Barbara S; Trimpin, Sarah

    2010-06-15

    Multiply charged ions, similar to those obtained with electrospray ionization, are produced at atmospheric pressure (AP) using standard MALDI conditions of laser fluence and reflective geometry. Further, the charge state can be switched to singly charged ions nearly instantaneously by changing the voltage applied to the MALDI target plate. Under normal AP-MALDI operating conditions in which a voltage is applied to the target plate, primarily singly charged ions are observed, but at or near zero volts, highly charged ions are observed for peptides and proteins. Thus, switching between singly and multiply charged ions requires only manipulation of a single voltage. As in ESI, multiple charging, produced using the AP-MALDI source, allows compounds with molecular weights beyond the mass-to-charge limit of the mass spectrometer to be observed and improves the fragmentation relative to singly charged ions.

  11. Experimental Characterization of Secular Frequency Scanning in Ion Trap Mass Spectrometers

    NASA Astrophysics Data System (ADS)

    Snyder, Dalton T.; Pulliam, Christopher J.; Wiley, Joshua S.; Duncan, Jason; Cooks, R. Graham

    2016-07-01

    Secular frequency scanning is implemented and characterized using both a benchtop linear ion trap and a miniature rectilinear ion trap mass spectrometer. Separation of tetraalkylammonium ions and those from a mass calibration mixture and from a pesticide mixture is demonstrated with peak widths approaching unit resolution for optimized conditions using the benchtop ion trap. The effects on the spectra of ion trap operating parameters, including waveform amplitude, scan direction, scan rate, and pressure are explored, and peaks at black holes corresponding to nonlinear (higher-order field) resonance points are investigated. Reverse frequency sweeps (increasing mass) on the Mini 12 are shown to result in significantly higher ion ejection efficiency and superior resolution than forward frequency sweeps that decrement mass. This result is accounted for by the asymmetry in ion energy absorption profiles as a function of AC frequency and the shift in ion secular frequency at higher amplitudes in the trap due to higher order fields. We also found that use of higher AC amplitudes in forward frequency sweeps biases ions toward ejection at points of higher order parametric resonance, despite using only dipolar excitation. Higher AC amplitudes also increase peak width and decrease sensitivity in both forward and reverse frequency sweeps. Higher sensitivity and resolution were obtained at higher trap pressures in the secular frequency scan, in contrast to conventional resonance ejection scans, which showed the opposite trend in resolution on the Mini 12. Mass range is shown to be naturally extended in secular frequency scanning when ejecting ions by sweeping the AC waveform through low frequencies, a method which is similar, but arguably superior, to the more usual method of mass range extension using low q resonance ejection.

  12. Operational Parameters, Considerations, and Design Decisions for Resource-Constrained Ion Trap Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    Danell, Ryan M.; VanAmerom, Friso H. W.; Pinnick, Veronica; Cotter, Robert J.; Brickerhoff, William; Mahaffy, Paul

    2011-01-01

    Mass spectrometers are increasingly finding applications in new and unique areas, often in situations where key operational resources (i.e. power, weight and size) are limited. One such example is the Mars Organic Molecule Analyzer (MOMA). This instrument is a joint venture between NASA and the European Space Agency (ESA) to develop an ion trap mass spectrometer for chemical analysis on Mars. The constraints on such an instrument are significant as are the performance requirements. While the ideal operating parameters for an ion trap are generally well characterized, methods to maintain analytical performance with limited power and system weight need to be investigated and tested. Methods Experiments have been performed on two custom ion trap mass spectrometers developed as prototypes for the MOMA instrument. This hardware consists of quadrupole ion trap electrodes that are 70% the size of common commercial instrumentation. The trapping RF voltage is created with a custom tank circuit that can be tuned over a range of RF frequencies and is driven using laboratory supplies and amplifiers. The entire instrument is controlled with custom Lab VIEW software that allows a high degree of flexibility in the definition of the scan function defining the ion trap experiment. Ions are typically generated via an internal electron ionization source, however, a laser desorption source is also in development for analysis of larger intact molecules. Preliminary Data The main goals in this work have been to reduce the power required to generate the radio frequency trapping field used in an ion trap mass spectrometer. Generally minimizing the power will also reduce the volume and mass of the electronics to support the instrument. In order to achieve optimum performance, commercial instruments typically utilize RF frequencies in the 1 MHz range. Without much concern for power usage, they simply generate the voltage required to access the mass range of interest. In order to reduce the

  13. Mass spectrometers: instrumentation

    NASA Astrophysics Data System (ADS)

    Cooks, R. G.; Hoke, S. H., II; Morand, K. L.; Lammert, S. A.

    1992-09-01

    Developments in mass spectrometry instrumentation over the past three years are reviewed. The subject is characterized by an enormous diversity of designs, a high degree of competition between different laboratories working with either different or similar techniques and by extremely rapid progress in improving analytical performance. Instruments can be grouped into genealogical charts based on their physical and conceptual interrelationships. This is illustrated using mass analyzers of different types. The time course of development of particular instrumental concepts is illustrated in terms of the s-curves typical of cell growth. Examples are given of instruments which are at the exponential, linear and mature growth stages. The prime examples used are respectively: (i) hybrid instruments designed to study reactive collisions of ions with surfaces: (ii) the Paul ion trap; and (iii) the triple quadrupole mass spectrometer. In the area of ion/surface collisions, reactive collisions such as hydrogen radical abstraction from the surface by the impinging ion are studied. They are shown to depend upon the chemical nature of the surface through the use of experiments which utilize self-assembled monolayers as surfaces. The internal energy deposited during surface-induced dissociation upon collision with different surfaces in a BEEQ instrument is also discussed. Attention is also given to a second area of emerging instrumentation, namely technology which allows mass spectrometers to be used for on-line monitoring of fluid streams. A summary of recent improvements in the performance of the rapidly developing quadrupole ion trap instrument illustrates this stage of instrument development. Improvements in resolution and mass range and their application to the characterization of biomolecules are described. The interaction of theory with experiment is illustrated through the role of simulations of ion motion in the ion trap. It is emphasized that mature instruments play a

  14. An electrospray ionization source for thermochemical investigation with the guided ion beam mass spectrometer.

    PubMed

    Moision, R M; Armentrout, P B

    2007-06-01

    An electrospray ionization (ESI) source developed for use with the guided ion beam tandem mass spectrometer (GIBMS) is described. For accurate determination of thermochemistry using threshold collision-induced dissociation (TCID), it is essential that any source produces ions with four exacting characteristics: (1) high intensity, (2) stable signal, and well-defined energies both (3) kinetic, and (4) internal. To accomplish these objectives, the ions generated by the electrospray are collected using a radio frequency electrodynamic ion funnel and are then transferred into a hexapole ion guide where they are thermalized and subsequently passed into higher-vacuum regions for analysis. The resulting ion intensities using this source can exceed 10(6) ions/s. Stable beams (<10% variation in signal) can be generated over multiple hours. The kinetic energy distribution of ions emerging from this source has been shown to be well described by a Gaussian distribution with a full width half maximum (FWHM) of about 0.1-0.2 eV in the laboratory frame of reference. Finally, TCID results for ions generated with this source show excellent agreement with previously reported threshold values for ions generated using a variety of sources and experimental methodologies. This confirms that internal energies of the ions are well described by a Maxwell-Boltzmann distribution at room temperature.

  15. Imaging and Rapid-Scanning Ion Mass Spectrometer (IRM) for the CASSIOPE e-POP Mission

    NASA Astrophysics Data System (ADS)

    Yau, Andrew W.; Howarth, Andrew; White, Andrew; Enno, Greg; Amerl, Peter

    2015-06-01

    The imaging and rapid-scanning ion mass spectrometer (IRM) is part of the Enhanced Polar Outflow Probe (e-POP) instrument suite on the Canadian CASSIOPE small satellite. Designed to measure the composition and detailed velocity distributions of ions in the ˜1-100 eV/q range on a non-spinning spacecraft, the IRM sensor consists of a planar entrance aperture, a pair of electrostatic deflectors, a time-of-flight (TOF) gate, a hemispherical electrostatic analyzer, and a micro-channel plate (MCP) detector. The TOF gate measures the transit time of each detected ion inside the sensor. The hemispherical analyzer disperses incident ions by their energy-per-charge and azimuth in the aperture plane onto the detector. The two electrostatic deflectors may be optionally programmed to step through a sequence of deflector voltages, to deflect ions of different incident elevation out of the aperture plane and energy-per-charge into the sensor aperture for sampling. The position and time of arrival of each detected ion at the detector are measured, to produce an image of 2-dimensional (2D), mass-resolved ion velocity distribution up to 100 times per second, or to construct a composite 3D velocity distribution by combining successive images in a deflector voltage sequence. The measured distributions are then used to investigate ion composition, density, drift velocity and temperature in polar ion outflows and related acceleration and transport processes in the topside ionosphere.

  16. Development of analytically capable time-of-flight mass spectrometer with continuous ion introduction

    NASA Astrophysics Data System (ADS)

    Hárs, György; Dobos, Gábor

    2010-03-01

    The present article describes the results and findings explored in the course of the development of the analytically capable prototype of continuous time-of-flight (CTOF) mass spectrometer. Currently marketed pulsed TOF (PTOF) instruments use ion introduction with a 10 ns or so pulse width, followed by a waiting period roughly 100 μs. Accordingly, the sample is under excitation in 10-4 part of the total measuring time. This very low duty cycle severely limits the sensitivity of the PTOF method. A possible approach to deal with this problem is to use linear sinusoidal dual modulation technique (CTOF) as described in this article. This way the sensitivity of the method is increased, due to the 50% duty cycle of the excitation. All other types of TOF spectrometer use secondary electron multiplier (SEM) for detection, which unfortunately discriminates in amplification in favor of the lighter ions. This discrimination effect is especially undesirable in a mass spectrometric method, which targets high mass range. In CTOF method, SEM is replaced with Faraday cup detector, thus eliminating the mass discrimination effect. Omitting SEM is made possible by the high ion intensity and the very slow ion detection with some hundred hertz detection bandwidth. The electrometer electronics of the Faraday cup detector operates with amplification 1010 V/A. The primary ion beam is highly monoenergetic due to the construction of the ion gun, which made possible to omit any electrostatic mirror configuration for bunching the ions. The measurement is controlled by a personal computer and the intelligent signal generator Type Tabor WW 2571, which uses the direct digital synthesis technique for making arbitrary wave forms. The data are collected by a Labjack interface board, and the fast Fourier transformation is performed by the software. Noble gas mixture has been used to test the analytical capabilities of the prototype setup. Measurement presented proves the results of the mathematical

  17. Ion neutral mass spectrometer results from the first flyby of Titan.

    PubMed

    Waite, J Hunter; Niemann, Hasso; Yelle, Roger V; Kasprzak, Wayne T; Cravens, Thomas E; Luhmann, Janet G; McNutt, Ralph L; Ip, Wing-Huen; Gell, David; De La Haye, Virginie; Müller-Wordag, Ingo; Magee, Brian; Borggren, Nathan; Ledvina, Steve; Fletcher, Greg; Walter, Erin; Miller, Ryan; Scherer, Stefan; Thorpe, Rob; Xu, Jing; Block, Bruce; Arnett, Ken

    2005-05-13

    The Cassini Ion Neutral Mass Spectrometer (INMS) has obtained the first in situ composition measurements of the neutral densities of molecular nitrogen, methane, molecular hydrogen, argon, and a host of stable carbon-nitrile compounds in Titan's upper atmosphere. INMS in situ mass spectrometry has also provided evidence for atmospheric waves in the upper atmosphere and the first direct measurements of isotopes of nitrogen, carbon, and argon, which reveal interesting clues about the evolution of the atmosphere. The bulk composition and thermal structure of the moon's upper atmosphere do not appear to have changed considerably since the Voyager 1 flyby.

  18. USING AN ACCURATE MASS, TRIPLE QUADRUPOLE MASS SPECTROMETER AND AN ION CORRELATION PROGRAM TO IDENTIFY COMPOUNDS

    EPA Science Inventory

    Most compounds are not found in mass spectral libraries and must be identified by other means. Often, compound identities can be deduced from the compositions of the ions in their mass spectra and review of the chemical literature. Confirmation is provided by mass spectra and r...

  19. Plasticizer contamination from vacuum system O-rings in a quadrupole ion trap mass spectrometer.

    PubMed

    Verge, Kent M; Agnes, George R

    2002-08-01

    The outgassing of plasticizers from Buna-N and Viton o-rings under vacuum lead to undesired ion-molecule chemistry in an Electrospray Quadrupole Ion Trap Mass Spectrometer. In experiments with the helium bath gas pressure >1.2 mTorr, or whenever analyte ions were stored for >100 ms, extensive loss of analyte ions by proton transfer or adduction with o-ring plasticizers bis(2-ethylhexyl) phthalate and bis(2-ethylhexyl) adipate occurred. A temporary solution to this contamination problem was found to be overnight refluxing in hexane of all the o-rings in the vacuum system. This procedure alleviated this plasticizer contamination for approximately 100 hours of operation. These results, and those that lead to identification of the contamination as plasticizers outgassing from o-rings are described.

  20. Broadscale resolving power performance of a high precision uniform field ion mobility-mass spectrometer.

    PubMed

    May, Jody C; Dodds, James N; Kurulugama, Ruwan T; Stafford, George C; Fjeldsted, John C; McLean, John A

    2015-10-21

    An extensive study of two current ion mobility resolving power theories ("conditional" and "semi-empirical") was undertaken using a recently developed drift tube ion mobility-mass spectrometer. The current study investigates the quantitative agreement between experiment and theory at reduced pressure (4 Torr) for a wide range of initial ion gate widths (100 to 500 μs), and ion mobility values (K0 from 0.50 to 3.0 cm(2) V(-1) s(-1)) representing measurements obtained in helium, nitrogen, and carbon dioxide drift gas. Results suggest that the conditional resolving power theory deviates from experimental results for low mobility ions (e.g., high mass analytes) and for initial ion gate widths beyond 200 μs. A semi-empirical resolving power theory provided close-correlation of predicted resolving powers to experimental results across the full range of mobilities and gate widths investigated. Interpreting the results from the semi-empirical theory, the performance of the current instrumentation was found to be highly linear for a wide range of analytes, with optimal resolving powers being accessible for a narrow range of drift fields between 14 and 17 V cm(-1). While developed using singly-charged ion mobility data, preliminary results suggest that the semi-empirical theory has broader applicability to higher-charge state systems.

  1. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer[S

    PubMed Central

    Zacek, Petr; Bukowski, Michael; Rosenberger, Thad A.; Picklo, Matthew

    2016-01-01

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PCs. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PCs. This approach is comprised of two MS methods: a precursor ion scanning (PIS) of mass m/z 184 in positive mode (PIS m/z +184) and MS3 fragmentation in negative mode, both performed on the same instrument, a hybrid triple quadrupole ion-trap mass spectrometer. The MS3 experiment identified the FA composition and the relative abundance of isobaric and sn-1, sn-2 positional isomeric PC species, which were subsequently combined with absolute quantitative data obtained by PIS m/z +184 scan. This approach was applied to the analysis of a National Institute of Standards and Technology human blood plasma standard reference material (SRM 1950). We quantified more than 70 PCs and confirmed that a majority are present in isobaric and isomeric mixtures. The FA content determined by this method was comparable to that obtained using GC with flame ionization detection, supporting the quantitative nature of this MS method. This methodology will provide more in-depth biomarker information for clinical and mechanistic studies. PMID:27688258

  2. Electrospray Ionization/Ion Mobility Spectrometer/Cylindrical Ion Trap Mass Spectrometer System for In-Situ Detection of Organic Compounds

    NASA Technical Reports Server (NTRS)

    Kanik, I.; Johnson, P. V.; Beegle, L. W.; Cooks, R. G.; Laughlin, B. C.; Hill, H. H.

    2003-01-01

    The potential of an Electrospray Ionization/Ion Mobility Spectrometer/Cylindrical Ion Trap Mass Spectrometer (ESI/IMS/CIT-MS) as an analytical instrument for analyzing material extracted from rock and soil samples as part of a suite of instruments on the proposed 2009 Mars Science Lander (MSL) will be demonstrated. This instrument will be able to identify volatile compounds as well as resident organic molecules on the parts-per-billion (ppb) level. Also, it will be able to obtain an inventory of chemical species on the surface of Mars which will result in a better understanding of ongoing surface chemistry. Finally, questions relevant to biological processes will be answered with the complete inventory of surface and near surface organic molecules that the ESI/IMS/CIT is capable of performing.

  3. An electrodynamic ion funnel interface for greater sensitivity and higher throughput with linear ion trap mass spectrometers

    SciTech Connect

    Page, Jason S.; Tang, Keqi; Smith, Richard D.

    2007-09-01

    An electrospray ionization interface incorporating an electrodynamic ion funnel has been designed and implemented in conjunction with a linear ion trap mass spectrometer (Thermo Electron, LTQ). We found ion transmission to be greatly improved by replacing the standard capillary-skimmer interface with the capillary-ion funnel interface. An infusion study using a serial dilution of a reserpine solution showed that ion injection times to fill the ion trap were reduced by ~90% which resulted in an ~10-fold increase in reported peak intensities. In liquid chromatography (LC)-MS and LC tandem MS (MS/MS) experiments performed using a proteomic sample from the bacterium, Shewanella oneidensis, the ion funnel interface provided an ~7-fold reduction in ion injection (accumulation) times. In a series of LC-MS/MS experiments we found that more dilute S. oneidensis samples provided more peptide and protein identifications when the ion funnel interface was used in place of the standard interface. This improvement was most pronounced at lower sample concentrations, where extended ion accumulation times are required, resulting in an ~2-fold increase in the number of protein identifications. Implementation of the ion funnel interface with a LTQ Fourier transform (FT) MS requiring much greater ion populations resulted in spectrum acquisition times reduced by ~25 to 50%.

  4. The Neutral Gas and Ion Mass Spectrometer on the Mars Atmosphere and Volatile Evolution Mission

    NASA Technical Reports Server (NTRS)

    Mahaffy, Paul R.; Benna, Mehdi; King, Todd; Harpold, Daniel N.; Arvey, Robert; Barciniak, Michael; Bendt, Mirl; Carrigan, Daniel; Errigo, Therese; Holmes, Vincent; Kellogg, James; Jaeger, Ferzan; Raaen, Eric; Tan, Florence

    2014-01-01

    The Neutral Gas and Ion Mass Spectrometer (NGIMS) of the Mars Atmosphere and Volatile Evolution Mission (MAVEN) is designed to measure the composition, structure, and variability of the upper atmosphere of Mars. The NGIMS complements two other instrument packages on the MAVEN spacecraft designed to characterize the neutral upper atmosphere and ionosphere of Mars and the solar wind input to this region of the atmosphere. The combined measurement set is designed to quantify atmosphere escape rates and provide input to models of the evolution of the martian atmosphere. The NGIMS is designed to measure both surface reactive and inert neutral species and ambient ions along the spacecraft track over the 125-500 km altitude region utilizing a dual ion source and a quadrupole analyzer.

  5. The Neutral Gas and Ion Mass Spectrometer on the Mars Atmosphere and Volatile Evolution Mission

    NASA Astrophysics Data System (ADS)

    Mahaffy, Paul R.; Benna, Mehdi; King, Todd; Harpold, Daniel N.; Arvey, Robert; Barciniak, Michael; Bendt, Mirl; Carrigan, Daniel; Errigo, Therese; Holmes, Vincent; Johnson, Christopher S.; Kellogg, James; Kimvilakani, Patrick; Lefavor, Matthew; Hengemihle, Jerome; Jaeger, Ferzan; Lyness, Eric; Maurer, John; Melak, Anthony; Noreiga, Felix; Noriega, Marvin; Patel, Kiran; Prats, Benito; Raaen, Eric; Tan, Florence; Weidner, Edwin; Gundersen, Cynthia; Battel, Steven; Block, Bruce P.; Arnett, Ken; Miller, Ryan; Cooper, Curt; Edmonson, Charles; Nolan, J. Thomas

    2015-12-01

    The Neutral Gas and Ion Mass Spectrometer (NGIMS) of the Mars Atmosphere and Volatile Evolution Mission (MAVEN) is designed to measure the composition, structure, and variability of the upper atmosphere of Mars. The NGIMS complements two other instrument packages on the MAVEN spacecraft designed to characterize the neutral upper atmosphere and ionosphere of Mars and the solar wind input to this region of the atmosphere. The combined measurement set is designed to quantify atmosphere escape rates and provide input to models of the evolution of the martian atmosphere. The NGIMS is designed to measure both surface reactive and inert neutral species and ambient ions along the spacecraft track over the 125-500 km altitude region utilizing a dual ion source and a quadrupole analyzer.

  6. Advanced Ion Mass Spectrometer for Giant Planet Ionospheres, Magnetospheres and Moons

    NASA Astrophysics Data System (ADS)

    Sittler, EC; Cooper, JF; Paschalidis, N.; Jones, SL; Rodriguez, M.; Ali, A.; Coplan, MA; Chornay, DJ; Sturner; Bateman, FB; Andre, N.; Fedorov, A.; Wurz, P.

    2015-10-01

    The Advanced Ion Composition Spectrometer (AIMS) has been under development from various NASA sources (NASA LWSID, NASA ASTID, NASA Goddard IRADs) to measure elemental, isotopic, and simple molecular composition abundances of 1 eV/e to 25 keV/e hot ions with wide field-of-view (FOV) in the 1 - 60 amu mass range at mass resolution M/ΔM ≤ 60 over a wide dynamic range of intensities and penetrating radiation background from the inner magnetospheres of Jupiter and Saturn to the outer magnetospheric boundary regions and the upstream solar wind. This instrument will work for both spinning spacecraft and 3-axis stabilized spacecraft with wide field-of-view capability in both cases. It will measure the ion velocity distribution functions (IVDF) for the individual ion species; ion velocity moments of the IVDF will give the fluid parameters (density, flow velocity and temperature) of the individual ion species. Outer planet mission applications are Io Observer, Jupiter Europa Orbiter/Europa Clipper, Enceladus Orbiter, and Uranus Orbiter as described in the decadal survey, but would also be valuable for inclusion on other missions to outer planet destinations such as Saturn- Titan and Neptune-Triton and for future missions to terrestrial planets, Venus and Mars, the Moon, asteroids, and comets, and of course for geospace applications to the Earth.

  7. Dual electrospray ion source for electron-transfer dissociation on a hybrid linear ion trap-orbitrap mass spectrometer.

    PubMed

    Williams, D Keith; McAlister, Graeme C; Good, David M; Coon, Joshua J; Muddiman, David C

    2007-10-15

    A dual electrospray ionization source (ESI) has been modified to simultaneously produce cations and anions, one from each emitter, for performing rapid electron-transfer dissociation (ETD) ion/ion reactions on a hybrid linear ion trap-orbitrap mass spectrometer. Unlike the pulsed dual ESI sources that were used to generate ETD reagent ions, this source separates the emitters in space, rather than time, by physically switching which one is in front of the atmospheric inlet. The new arrangement allows for substantially enhanced spray stability and decreased switching times (ions from multiply protonated peptide cations.

  8. A Dual Source Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer of ExoMars 2018

    NASA Technical Reports Server (NTRS)

    Brickerhoff, William B.; vanAmerom, F. H. W.; Danell, R. M.; Arevalo, R.; Atanassova, M.; Hovmand, L.; Mahaffy, P. R.; Cotter, R. J.

    2011-01-01

    We present details on the objectives, requirements, design and operational approach of the core mass spectrometer of the Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars mission. The MOMA mass spectrometer enables the investigation to fulfill its objective of analyzing the chemical composition of organic compounds in solid samples obtained from the near surface of Mars. Two methods of ionization are realized, associated with different modes of MOMA operation, in a single compact ion trap mass spectrometer. The stringent mass and power constraints of the mission have led to features such as low voltage and low frequency RF operation [1] and pulse counting detection.

  9. ILMA: Ion Laser Mass Analyser. A Mass-Spectrometer for In-Situ Characterization of a Near Earth Object (NEO)

    NASA Astrophysics Data System (ADS)

    Cottin, Hervé; Arezki, B.; Berthelier, J. J.; Bouabdellah, A.; Boukrara, A.; Briois, C.; Carrasco, N.; Gilbert, P.; Engrand, C.; Grand, N.; Hilchenbach, M.; Krüger, H.; Makarov, A.; Pennanech, C.; Puget, P.; Quirico, E.; Szopa, C.; Thirkell, L.; Zapf, P.; Thissen, R.

    Like other small bodies of the Solar System, asteroids are the remnants of planet formation. Their compositions are inherited from the Solar Nebula at the time of planetesimals accretion into planets, 4.5 billion years ago. They are valuable objects to assess the physicochemical conditions prevailing at the time and place of their formation in the Solar Nebula. Among them, some are known to be rich in carbon and volatile species (including water), which suggests that they never underwent major heating and differentiation events. Their organic content is also of prime interest because the chemical evolution leading to life on Earth may have been initiated by the delivery of extraterrestrial organic compounds into primitive oceans. For these reasons, several space missions are currently considered by ESA and JAXA for a sample return mission to a primitive carbonaceous Near-Earth Object (NEO): MARCO POLO, HAYABUZA 2, etc... Their goal is to characterize a NEO at multiple scales via in-situ measurements by a science payload onboard an orbiter and a lander, and to bring samples back to Earth. ILMA is a concept for a new generation high resolution mass spectrometer, proposed to be part of a lander payload for in situ science. This instrument will be a Fourier Transform ion trap mass spectrometer using Laser Desorption and Ionization Mass Spectrometry (LDIMS) into a single platform. To this end, an Orbitrap mass analyser (developed by the Thermofisher Company) will be coupled to a laser source. The sample will be exposed to the laser beam producing desorbed ions which will be collected into the ion trap using the orbital trapping method. Ions will be stabilized in the trap by purely electrostatic quadro-logarithmic electrical fields and the detection undertaken by a non destructive measurement of the ion oscillation frequency inside the trap. Indeed, the trapped ions induce a periodic signal converted using Fourier Transform (FT) into an ultra-high mass resolution

  10. Study and evaluation of impulse mass spectrometers for ion analysis in the D and E regions of the ionosphere

    NASA Technical Reports Server (NTRS)

    Kendall, B. R.

    1979-01-01

    Theoretical and numerical analyses were made of planar, cylindrical and spherical electrode time-of-flight mass spectrometers in order to optimize their operating conditions. A numerical analysis of potential barrier gating in time-of-flight spectrometers was also made. The results were used in the design of several small mass spectrometers. These were constructed and tested in a laboratory space simulator. Detailed experimental studies of a miniature cylindrical electrode time of flight mass spectrometer and of a miniature hemispherical electrode time of flight mass spectrometer were made. The extremely high sensitivity of these instruments and their ability to operate at D region pressures with an open source make them ideal instruments for D region ion composition measurements.

  11. Measurement of Atmospheric Isoprene Concentrations using an Automated Cylindrical Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Edwards, G. D.; Shepson, P. B.; Grossenbacher, J. W.; Wells, J. M.; Patterson, G.; Barkett, D. J.

    2005-12-01

    Volatile organic compounds (VOCs) released from the biosphere have been shown to substantially influence both ozone and aerosol chemistry. However, field instruments for the detection of these trace gases are often limited by instrument portability and the ability to distinguish compounds of interest from background or other interfering compounds. We have developed an automated sampling system that is coupled to a lightweight, low power cylindrical ion trap mass spectrometer. This instrument was used for high frequency isoprene measurements at a recent field campaign at the University of Michigan Biological Station PROPHET lab. The inlet uses a sample loop and 6-port valves to trap ambient air samples without the aid of cryogens. VOCs are preconcentrated by sampling directly into a pre-cooled capillary column that is then heated by moving the column to a pre-heated region to obtain rapid separation of isoprene from other species. Isoprene eluting from the end of the column is then introduced to the mass spectrometer. The commercially available cylindrical ion trap (Minotaur 400) interfaced with our preconcentrator yields limits of detection of <80 ppt. The data obtained during the PROPHET 2005 campaign suggest the new inlet system, when coupled with the Minotaur 400 detector provides a feasible field instrument for the fast and accurate evaluation of trace gases over a variety of atmospheric conditions.

  12. Using Metal Complex Ion-Molecule Reactions in a Miniature Rectilinear Ion Trap Mass Spectrometer to Detect Chemical Warfare Agents

    NASA Astrophysics Data System (ADS)

    Graichen, Adam M.; Vachet, Richard W.

    2013-06-01

    The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n]y+ complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n]2+ complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.

  13. Using metal complex ion-molecule reactions in a miniature rectilinear ion trap mass spectrometer to detect chemical warfare agents.

    PubMed

    Graichen, Adam M; Vachet, Richard W

    2013-06-01

    The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n](y+) complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n](2+) complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.

  14. Miniaturized Ion and Neutral Mass Spectrometer for CubeSat Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Rodriguez, M.; Paschalidis, N.; Jones, S.; Sittler, E.; Chornay, D.; Uribe, P.; Cameron, T.

    2016-01-01

    To increase the number of single point in-situ measurements of thermosphere and exosphere ion and neutral composition and density, miniaturized instrumentation is in high demand to take advantage of the increasing platform opportunities available in the smallsat/cubesat industry. The INMS (Ion-Neutral Mass Spectrometer) addresses this need by providing simultaneous measurements of both the neutral and ion environment, essentially providing two instruments in one compact model. The 1.3U volume, 570 gram, 1.8W nominal power INMS instrument makes implementation into cubesat designs (3U and above) practical and feasible. With high dynamic range (0.1-500eV), mass dynamic range of 1-40amu, sharp time resolution (0.1s), and mass resolution of MdM16, the INMS instrument addresses the atmospheric science needs that otherwise would have required larger more expensive instrumentation. INMS-v1 (version 1) launched on Exocube (CalPoly 3U cubesat) in 2015 and INMS-v2 (version 2) is scheduled to launch on Dellingr (GSFC 6U cubesat) in 2017. New versions of INMS are currently being developed to increase and add measurement capabilities, while maintaining its smallsat/cubesat form.

  15. Ultra High Mass Range Mass Spectrometer System

    DOEpatents

    Reilly, Peter T. A. [Knoxville, TN

    2005-12-06

    Applicant's present invention comprises mass spectrometer systems that operate in a mass range from 1 to 10.sup.16 DA. The mass spectrometer system comprising an inlet system comprising an aerodynamic lens system, a reverse jet being a gas flux generated in an annulus moving in a reverse direction and a multipole ion guide; a digital ion trap; and a thermal vaporization/ionization detector system. Applicant's present invention further comprises a quadrupole mass spectrometer system comprising an inlet system having a quadrupole mass filter and a thermal vaporization/ionization detector system. Applicant's present invention further comprises an inlet system for use with a mass spectrometer system, a method for slowing energetic particles using an inlet system. Applicant's present invention also comprises a detector device and a method for detecting high mass charged particles.

  16. Development of a linear ion trap/orthogonal-time-of-flight mass spectrometer for time-dependent observation of product ions by ultraviolet photodissociation of peptide ions.

    PubMed

    Kim, Tae-Young; Schwartz, Jae C; Reilly, James P

    2009-11-01

    A hybrid linear ion trap/orthogonal time-of-flight (TOF) mass spectrometer has been developed to observe time-dependent vacuum ultraviolet photodissociation product ions. In this apparatus, a reflectron TOF mass analyzer is orthogonally interfaced to an LTQ using rf-only octopole and dc quadrupole ion guides. Precursor ions are generated by electrospray ionization and isolated in the ion trap. Subsequently they are directed to the TOF source where photodissociation occurs and product ions are extracted for mass analysis. To detect photodissociation product ions having axially divergent trajectories, a large rectangular detector is utilized. With variation of the time between photodissociation and orthogonal extraction in the TOF source, product ions formed over a range of times after photoexcitation can be sampled. Time-dependent observation of product ions following 157 nm photodissociation of a singly charged tryptic peptide ion (NWDAGFGR) showed that prompt photofragment ions (x- and v-type ions) dominate the tandem mass spectrum up to 1 micros after the laser shot, but the intensities of low energy thermal fragment ions (y-type ions) become comparable several microseconds later. Different proton mobilization time scales were observed for arginine- and lysine-terminated tryptic peptides.

  17. Investigating ion-surface collisions with a niobium superconducting tunnel junction detector in a time-of-flight mass spectrometer

    SciTech Connect

    Westmacott, G.; Zhong, F.; Frank, M.; Friedrich, S.; Labov, S.; Benner, W.H.

    1999-12-01

    The performance of an energy sensitive, niobium superconducting tunnel junction detector is investigated by measuring the pulse height produced by impacting molecular and atomic ions at different kinetic energies. Ions are produced by laser resorption and matrix-assisted laser desorption in a time-of-flight mass spectrometer. Results show that the STJ detector pulse height decreases for increasing molecular ion mass, passes through a minimum at around 2000 Da, and the increases with increasing mass of molecular ions above 2000Da. The detector does not show a decline in sensitivity for high mass ions as is observed with microchannel plate ion detectors. These detector plus height measurements are discussed in terms of several physical mechanisms involved in an ion-surface collision.

  18. Method for calibrating a Fourier transform ion cyclotron resonance mass spectrometer

    DOEpatents

    Smith, Richard D.; Masselon, Christophe D.; Tolmachev, Aleksey

    2003-08-19

    A method for improving the calibration of a Fourier transform ion cyclotron resonance mass spectrometer wherein the frequency spectrum of a sample has been measured and the frequency (f) and intensity (I) of at least three species having known mass to charge (m/z) ratios and one specie having an unknown (m/z) ratio have been identified. The method uses the known (m/z) ratios, frequencies, and intensities at least three species to calculate coefficients A, B, and C, wherein the mass to charge ratio of a least one of the three species (m/z).sub.i is equal to ##EQU1## wherein f.sub.i is the detected frequency of the specie, G(I.sub.i) is a predetermined function of the intensity of the species, and Q is a predetermined exponent. Using the calculated values for A, B, and C, the mass to charge ratio of the unknown specie (m/z).sub.ii is calculated as the sum of ##EQU2## wherein f.sub.ii is the measured frequency of the unknown specie, and (I.sub.ii) is the measured intensity of the unknown specie.

  19. A Compact Ion and Neutral Mass Spectrometer for the Exocube Mission

    NASA Astrophysics Data System (ADS)

    Jones, S.; Paschalidis, N.; Rodriguez, M.; Sittler, E. C., Jr.; Chornay, D. J.

    2014-12-01

    Demand is high for in situ measurements of atmospheric neutral and ion composition and density, not only for studies of the dynamic ionosphere-theremosphere-mesosphere system but simply to define the steady state background atmospheric conditions. The ExoCube mission is designed to acquire global knowledge of in-situ densities of [H], [He], [O] and [H+], [He+], [O+] in the upper ionosphere and lower exosphere in combination with incoherent scatter radar ground stations distributed in the north polar region. The Heliophysic Division of GSFC has developed a compact Ion and Neutral Mass Spectrometer (INMS) for in situ measurements of ions and neutrals H, He, N, O, N2, O2 with M/dM of approximately 10 at an incoming energy range of 0-50eV. The INMS is based on front end optics, post acceleration, gated time of flight, ESA and CEM or MCP detectors. The compact sensor has a dual symmetric configuration with the ion and neutral sensor heads on opposite sides and with full electronics in the middle. The neutral front end optics includes thermionic emission ionization and ion blocking grids, and the ion front end optics includes spacecraft potential compensation grids. The electronics include front end, fast gating, HVPS, ionizer, TOF binning and full bi directional C&DH digital electronics. The data package includes 400 mass bins each for ions and neutrals and key housekeeping data for instrument health and calibration. The data sampling can be commanded as fast as 10 msec per frame (corresponding to ~80 m spatial separation) in burst mode, and has significant onboard storage capability and data compression scheme. Experimental data from instrument testing with both ions and neutrals will be presented. The instrument is successfully integrated in the CubeSat and passed vibration, thermal and shock testing. The ExoCube mission is scheduled to fly in Nov 2014 in a 445 x 670 km polar orbit with the INMS aperture oriented in the ram direction. This miniaturized instrument (1

  20. Continuation of data analysis from the ion mass spectrometer on the ISIS-2 spacecraft

    NASA Technical Reports Server (NTRS)

    Hoffman, J. H.

    1981-01-01

    The spectrometer measures the composition and number density of the positive ion species in the ionosphere as well as the ion flux normal to the spacecraft trajectory. The measurement of high latitude ionospheric dynamics is reported. Plans for an empirical composition model of the polar ionosphere at 1400 km altitude consisting of maps of the major constituent are also reported.

  1. Development of Ion and Neutral Mass Spectrometers (INMS) for Heliophysics and Planetary Missions

    NASA Astrophysics Data System (ADS)

    Sittler, Edward; Paschalidis, Nikolaos; Cooper, John; Zesta, Eftyhia; Ali, Ashraf; Chornay, Dennis; Durachka, David; Brambora, Clifford; Benna, Mehdi; Mahaffy, Paul

    2014-05-01

    Goddard's Geospace Physics Laboratory is developing INMS concepts that can be used for future Geospace missions to the Earth's ionosphere and for future planetary missions to bodies with atmospheres and ionospheres, in collaboration with the Planetary Environments Laboratory. Our group is designing ion mass spectrometers (IMS) for energy-per-charge range 1 V to 50 kV that can be used for solar wind ion composition measurements, the Earth's magnetosphere , lunar orbiters, and planetary magnetospheres. We will focus this presentation in our efforts and results for future CubeSat Missions to the Earth's ionosphere and a High Precision Electric Gate (HPEG) design that can be used with a reflectometer to achieve very high mass resolution capability. The HPEG design has been patented by Goddard with E. C. Sittler Jr. as inventor. The HPEG design allows for miniaturization so it is ideally suited to CubeSat missions. Engineers at Goddard's Instrument Electronics Development Branch have prototyped a pulse generator that can deliver a required train of pulses with ~ ns pulses on a Field Programmable Gate Array (FPGA) platform that will allow miniature designs of the HPEG. The burst of pulses can be triggered at MHz rates. We will present initial lab results for a simpler CubeSat design instrument and a more complex version using the HPEG.

  2. Development of an Ion Mobility Spectrometry-Orbitrap Mass Spectrometer Platform

    SciTech Connect

    Ibrahim, Yehia M.; Garimella, Sandilya V. B.; Prost, Spencer A.; Wojcik, Roza; Norheim, Randolph V.; Baker, Erin S.; Rusyn, Ivan; Smith, Richard D.

    2016-12-20

    Complex samples benefit from multidimensional measurements where higher resolution enables more complete characterization of biological and environmental systems. To address this challenge, we developed a drift tube-based ion mobility spectrometry-Orbitrap mass spectrometer (IMS-Orbitrap MS) platform. To circumvent the time scale disparity between the fast IMS separation and the much slower Orbitrap MS acquisition, we utilized a dual gate and pseudorandom sequences to multiplexed injection of ions and allowing operation in signal averaging (SA), single multiplexing (SM) and double multiplexing (DM) IMS modes to optimize the signal-to-noise ratio of the measurements. For the SM measurements, a previously developed algorithm was used to reconstruct the IMS data. A new algorithm was developed for the DM analyses involving a two-step process that first recovers the SM data and then decodes the SM data. The algorithm also performs multiple refining procedures in order to minimize demultiplexing artifacts. The new IMS-Orbitrap MS platform was demonstrated by the analysis of proteomic and petroleum samples, where the integration of IMS and high mass resolution proved essential for accurate assignment of molecular formulae.

  3. Miniaturized system of a gas chromatograph coupled with a Paul ion trap mass spectrometer

    NASA Technical Reports Server (NTRS)

    Shortt, B. J.; Darrach, M. R.; Holland, Paul M.; Chutjian, A.

    2005-01-01

    Miniature gas chromatography (GC) and miniature mass spectrometry (MS) instrumentation has been developed to identify and quantify the chemical compounds present in complex mixtures of gases. The design approach utilizes micro-GC components coupled with a Paul quadrupole ion trap (QIT) mass spectrometer. Inherent to the system are high sensitivity, good dynamic range, good QIT resolution, low GC flow-rates to minimize vacuum requirements and the need for consumables; and the use of a modular approach to adapt to volatile organic compounds dissolved in water or present in sediment. Measurements are reported on system response to gaseous species at concentrations varying over four orders of magnitude. The ability of the system to deal with complicated mixtures is demonstrated, and future improvements are discussed. The GC/QIT system described herein has a mass, volume and power that are, conservatively, one-twentieth of those of commercial off-the-shelf systems. Potential applications are to spacecraft cabin-air monitoring, robotic planetary exploration and trace-species detection for residual gas analysis and environmental monitoring.

  4. Development of a Linear Ion Trap Mass Spectrometer (LITMS) Investigation for Future Planetary Surface Missions

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, W.; Danell, R.; Van Ameron, F.; Pinnick, V.; Li, X.; Arevalo, R.; Glavin, D.; Getty, S.; Mahaffy, P.; Chu, P.; Zacny, K.; Rogacki, S.; Grubisic, A.; Cornish, T.

    2014-01-01

    Future surface missions to Mars and other planetary bodies will benefit from continued advances in miniature sensor and sample handling technologies that enable high-performance chemical analyses of natural samples. Fine-scale (approx.1 mm and below) analyses of rock surfaces and interiors, such as exposed on a drill core, will permit (1) the detection of habitability markers including complex organics in association with their original depositional environment, and (2) the characterization of successive layers and gradients that can reveal the time-evolution of those environments. In particular, if broad-based and highly-sensitive mass spectrometry techniques could be brought to such scales, the resulting planetary science capability would be truly powerful. The Linear Ion Trap Mass Spectrometer (LITMS) investigation is designed to conduct fine-scale organic and inorganic analyses of short (approx.5-10 cm) rock cores such as could be acquired by a planetary lander or rover arm-based drill. LITMS combines both pyrolysis/gas chromatograph mass spectrometry (GCMS) of sub-sampled core fines, and laser desorption mass spectrometry (LDMS) of the intact core surface, using a common mass analyzer, enhanced from the design used in the Mars Organic Molecule Analyzer (MOMA) instrument on the 2018 ExoMars rover. LITMS additionally features developments based on the Sample Analysis at Mars (SAM) investigation on MSL and recent NASA-funded prototype efforts in laser mass spectrometry, pyrolysis, and precision subsampling. LITMS brings these combined capabilities to achieve its four measurement objectives: (1) Organics: Broad Survey Detect organic molecules over a wide range of molecular weight, volatility, electronegativity, concentration, and host mineralogy. (2) Organic: Molecular Structure Characterize internal molecular structure to identify individual compounds, and reveal functionalization and processing. (3) Inorganic Host Environment Assess the local chemical

  5. Investigation of Luna-20 soil samples, using a mass spectrometer with a spark-discharge ion source

    NASA Technical Reports Server (NTRS)

    Hubbard, N. J.; Ramendik, G. I.; Gronskaia, S. I.; Gubina, I. IA.; Gushchin, V. N.

    1979-01-01

    A method of analyzing soil samples with a mass spectrometer employing a spark-discharge ion source is described, and the effectiveness of the method is demonstrated by applying it to the determination of impurities, in amounts of less than 10 mg, in lunar samples. It is shown that four parts of the Luna-20 lunar highland sample differ in their chemical composition.

  6. Design of a new multi-turn ion optical system 'IRIS' for a time-of-flight mass spectrometer.

    PubMed

    Nishiguchi, Masaru; Ueno, Yoshihiro; Toyoda, Michisato; Setou, Mitsutoshi

    2009-05-01

    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.

  7. Portable Tandem Mass Spectrometer Analyzer

    DTIC Science & Technology

    1991-07-01

    The planned instrument was to be small enough to be portable in small vehicles and was to be able to use either an atmospheric pressure ion source or a...conventional electron impact/chemical ionization ion source. In order to accomplish these developments an atmospheric pressure ionization source was...developed for a compact, commercially available tandem quadrupole mass spectrometer. This ion source could be readily exchanged with the conventional

  8. MSM, an Efficient Workflow for Metabolite Identification Using Hybrid Linear Ion Trap Orbitrap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Cho, Robert; Huang, Yingying; Schwartz, Jae C.; Chen, Yan; Carlson, Timothy J.; Ma, Ji

    2012-05-01

    Identification of drug metabolites can often yield important information regarding clearance mechanism, pharmacologic activity, or toxicity for drug candidate molecules. Additionally, the identification of metabolites can provide beneficial structure-activity insight to help guide lead optimization efforts towards molecules with optimal metabolic profiles. There are challenges associated with detecting and identifying metabolites in the presence of complex biological matrices, and new LC-MS technologies have been developed to meet these challenges. In this report, we describe the development of an experimental approach that applies unique features of the hybrid linear ion trap Orbitrap mass spectrometer to streamline in vitro and in vivo metabolite identification experiments. The approach, referred to as MSM, utilizes multiple collision cells, dissociation methods, mass analyzers, and detectors. With multiple scan types and different dissociation modes built into one experimental method, along with flexible post-acquisition analysis options, the MSM workflow offers an attractive option to fast and reliable identification of metabolites in different kinds of in vitro and in vivo samples. The MSM workflow was successfully applied to metabolite identification analysis of verapamil in both in vitro rat hepatocyte incubations and in vivo rat bile samples.

  9. A Virtual Research Environment for a Secondary Ion Mass Spectrometer (SIMS)

    NASA Astrophysics Data System (ADS)

    Wiedenbeck, M.; Schäfer, L.; Klump, J.; Galkin, A.

    2013-12-01

    Overview: This poster describes the development of a Virtual Research Environment for the Secondary Ion Mass Spectrometer (SIMS) at GFZ Potsdam. Background: Secondary Ion Mass Spectrometers (SIMS) are extremely sensitive instruments for analyzing the surfaces of solid and thin film samples. These instruments are rare, expensive and experienced operators are very highly sought after. As such, measurement time is a precious commodity, until now only accessible to small numbers of researchers. The challenge: The Virtual SIMS Project aims to set up a Virtual Research Environment for the operation of the CAMECA IMS 1280-HR instrument at the GFZ Potsdam. The objective of the VRE is to provide SIMS access not only to researchers locally present in Potsdam but also to scientists working with SIMS cooperation partners in e.g., South Africa, Brazil or India. The requirements: The system should address the complete spectrum of laboratory procedures - from online application for measurement time, to remote access for data acquisition to data archiving for the subsequent publication and for future reuse. The approach: The targeted Virtual SIMS Environment will consist of a: 1. Web Server running the Virtual SIMS website providing general information about the project, lab access proposal forms and calendar for the timing of project related tasks. 2. LIMS Server, responsible for scheduling procedures, data management and, if applicable, accounting and billing. 3. Remote SIMS Tool, devoted to the operation of the experiment within a remote control environment. 4. Publishing System, which supports the publication of results in cooperation with the GFZ Library services. 5. Training Simulator, which offers the opportunity to rehearse experiments and to prepare for possible events such as a power outages or interruptions to broadband services. First results: The SIMS Virtual Research Environment will be mainly based on open source software, the only exception being the CAMECA IMS

  10. Imaging mass spectrometer with mass tags

    DOEpatents

    Felton, James S.; Wu, Kuang Jen J.; Knize, Mark G.; Kulp, Kristen S.; Gray, Joe W.

    2013-01-29

    A method of analyzing biological material by exposing the biological material to a recognition element, that is coupled to a mass tag element, directing an ion beam of a mass spectrometer to the biological material, interrogating at least one region of interest area from the biological material and producing data, and distributing the data in plots.

  11. Imaging mass spectrometer with mass tags

    DOEpatents

    Felton, James S.; Wu, Kuang Jen; Knize, Mark G.; Kulp, Kristen S.; Gray, Joe W.

    2010-06-01

    A method of analyzing biological material by exposing the biological material to a recognition element, that is coupled to a mass tag element, directing an ion beam of a mass spectrometer to the biological material, interrogating at least one region of interest area from the biological material and producing data, and distributing the data in plots.

  12. Miniaturised TOF mass spectrometer

    NASA Astrophysics Data System (ADS)

    Rohner, U.; Wurz, P.; Whitby, J.

    2003-04-01

    For the BepiColombo misson of ESA to Mercury, we built a prototype of a miniaturised Time of Flight mass spectrometer with a low mass and low power consumption. Particles will be set free form the surface and ionized by short laser pluses. The mass spectrometer is dedicated to measure the elemental and isotopic composition of almost all elements of Mercurys planetary surface with an adequate dynamique range, mass range and mass resolution. We will present first results of our prototype and future designs.

  13. Inductively coupled plasma mass spectrometer with laser ablation metal ions release detection in the human mouth

    NASA Astrophysics Data System (ADS)

    Kueerova, Hana; Dostalova, Tatjana; Prochazkova, J.

    2002-06-01

    Presence of more dental alloys in oral cavity often causes pathological symptoms. Due to various and multi-faced symptomatology, they tend to be a source of significant problems not only for the patient but also for the dentist. Metal ions released from alloys can cause subjective and objective symptoms in mouth. The aim of this study was detection of metal elements presence in saliva. There were 4 groups of examined persons: with intact teeth (15 individuals) with metallic restorations, pathological currents 5-30 (mu) A, multi-faced subjective symptomatology and uncharacteristic objective diagnosis (32 patients), with metallic restorations and no subjective symptoms (14 persons) and with metallic restorations, without pathological currents and with problems related to galvanism (13 patients). Presence of 14 metal elements was checked by inductively coupled plasma mass spectrometer with laser ablation. Nd:YAG laser detector was used. There were significant differences in content of silver, gold and mercury between persons with intact teeth and other three groups. There were no differences found between subjects with and without galvanic currents, and presence of subjective and objective symptoms.

  14. Temperature Variations in the Martian Upper Atmosphere from the MAVEN Neutral Gas and Ion Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Stone, Shane W.; Yelle, Roger; Mahaffy, Paul; Benna, Mehdi; Elrod, Meredith K.; Bougher, Stephen W.; MAVEN

    2016-10-01

    The MAVEN Neutral Gas and Ion Mass Spectrometer (NGIMS) measures composition and variability of neutral and ionic species in the Martian upper atmosphere, allowing us to calculate neutral temperatures from roughly 130 km to 300 km above the surface. Over the past two years at Mars, NGIMS has collected an extensive and useful data set that covers much of the Martian thermosphere and exosphere. We use new, improved algorithms for the most accurate determination of densities from the NGIMS data. We use the densities of inert species (specifically CO2, Ar, and N2) along with a hydrostatic equilibrium model to infer the temperature profile and its uncertainty. Uncertainties include the errors in the density measurements, unknown upper boundary conditions, and horizontal variations in the atmosphere. Our calculations reveal diurnal temperature variations of up to 90 K and maximum latitudinal temperature variations of 130 K. These fluctuations in temperature in the upper atmosphere are surprising because they are significantly larger than those predicted by the latest 3D general circulation models for Mars.

  15. NEGATIVE ION ELECTROSPRAY OF BROMO- AND CHLORACETIC ACIDS AND AN EVALUATION OF EXACT MASS MEASUREMENTS WITH A BENCH-TOP TIME-OF-FLIGHT MASS SPECTROMETER

    EPA Science Inventory

    The negative ion electrospray mass spectra of six bromo- and chloroacetic acids were measured using two different electrospray interfaces and single quadrupole and bench-top time-of-flight mass spectrometers. With each acid at 50 ug/mL in aqueous methanol at pH 10, the anions ob...

  16. Miniaturized Ion Mobility Spectrometer

    NASA Technical Reports Server (NTRS)

    Kaye, William J. (Inventor); Stimac, Robert M. (Inventor)

    2015-01-01

    By utilizing the combination of a unique electronic ion injection control circuit in conjunction with a particularly designed drift cell construction, the instantly disclosed ion mobility spectrometer achieves increased levels of sensitivity, while achieving significant reductions in size and weight. The instant IMS is of a much simpler and easy to manufacture design, rugged and hermetically sealed, capable of operation at high temperatures to at least 250.degree. C., and is uniquely sensitive, particularly to explosive chemicals.

  17. Time of flight mass spectrometer

    DOEpatents

    Ulbricht, Jr., William H.

    1984-01-01

    A time-of-flight mass spectrometer is described in which ions are desorbed from a sample by nuclear fission fragments, such that desorption occurs at the surface of the sample impinged upon by the fission fragments. This configuration allows for the sample to be of any thickness, and eliminates the need for complicated sample preparation.

  18. Optimized precursor ion selection for labile ions in a linear ion trap mass spectrometer and its impact on quantification using selected reaction monitoring.

    PubMed

    Lee, Hyun-Seok; Shin, Kyong-Oh; Jo, Sung-Chan; Lee, Yong-Moon; Yim, Yong-Hyeon

    2014-12-01

    The fragmentation of fragile ions during the application of an isolation waveform for precursor ion selection and the resulting loss of isolated ion intensity is well-known in ion trap mass spectrometry (ITMS). To obtain adequate ion intensity in the selected reaction monitoring (SRM) of fragile precursor ions, a wider ion isolation width is required. However, the increased isolation width significantly diminishes the selectivity of the channels chosen for SRM, which is a serious problem for samples with complex matrices. The sensitive and selective quantification of many lipid molecules, including ceramides from real biological samples, using a linear ion trap mass spectrometer is also hindered by the same problem because of the ease of water loss from protonated ceramide ions. In this study, a method for the reliable quantification of ceramides using SRM with near unity precursor ion isolation has been developed for ITMS by utilizing alternative precursor ions generated by in-source dissociation. The selected precursor ions allow the isolation of ions with unit mass width and the selective analysis of ceramides using SRM with negligible loss of sensitivity. The quantification of C18:0-, C24:0- and C24:1-ceramides using the present method shows excellent linearity over the concentration ranges from 6 to 100, 25 to 1000 and 25 to 1000 nM, respectively. The limits of detection of C18:0-, C24:0- and C24:1-ceramides were 0.25, 0.25 and 5 fmol, respectively. The developed method was successfully applied to quantify ceramides in fetal bovine serum.

  19. Preparation and in situ characterization of surfaces using soft landing in a Fourier transform ion cyclotron resonance mass spectrometer.

    PubMed

    Alvarez, Jormarie; Cooks, R Graham; Barlow, S E; Gaspar, Daniel J; Futrell, Jean H; Laskin, Julia

    2005-06-01

    Mass-selected peptide ions produced by electrospray ionization were deposited onto fluorinated self-assembled monolayer surfaces (FSAM) surfaces by soft landing using a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially designed for studying interactions of large ions with surfaces. Analysis of the modified surface was performed in situ by combining 2-keV Cs+ secondary ion mass spectrometry with FT-ICR detection of the sputtered ions (FT-ICR-SIMS). Regardless of the initial charge state of the precursor ion, the SIMS mass spectra included singly protonated peptide ion, peptide fragment ions, and peaks characteristic of the surface in all cases. In some experiments, multiply protonated peptide ions and [M + Au]+ ions were also observed upon SIMS analysis of modified surfaces. For comparison with the in situ analysis of the modified surfaces, ex situ analysis of some of the modified surfaces was performed by 25-keV Ga+ time-of-flight-secondary ion mass spectrometry (TOF-SIMS). The ex situ analysis demonstrated that a significant number of soft-landed peptide ions remain charged on the surface even when exposed to air for several hours after deposition. Charge retention of soft-landed ions dramatically increases the ion yields obtained during SIMS analysis and enables very sensitive detection of deposited material at less than 1% of monolayer coverage. Accumulation of charged species on the surface undergoes saturation due to coulomb repulsion between charges at close to 30% coverage. We estimated that close to 1 ng of peptide could be deposited on the spot area of 4 mm2 of the FSAM surface without reaching saturation.

  20. Quantitative profiling of phospholipids by multiple precursor ion scanning on a hybrid quadrupole time-of-flight mass spectrometer.

    PubMed

    Ekroos, Kim; Chernushevich, Igor V; Simons, Kai; Shevchenko, Andrej

    2002-03-01

    A hybrid quadrupole time-of-flight mass spectrometer featured with ion trapping capabilities was employed for quantitative profiling of total extracts of endogenous phospholipids. Simultaneous acquisition of precursor ion spectra of multiple fragment ions allowed detection of major classes of phospholipids in a single experiment. Relative changes in their concentration were monitored using a mixture of isotopically labeled endogenous lipids as a comprehensive internal standard. Precursor ion scanning spectra were acquired simultaneously for acyl anions of major fatty acids in negative ion mode and identified the fatty acid moieties and their relative position at the glycerol backbone in individual lipid species. Taken together, a combination of multiple precursor ion scans allowed quantitative monitoring of major perturbation in phospholipid composition and elucidating of molecular heterogeneity of individual lipid species.

  1. Direct Chemical Analysis of Solids by Laser Ablation in an Ion-Storage Time-of-Flight Mass Spectrometer

    SciTech Connect

    Klunder, G L; Grant, P M; Andresen, B D; Russo, R E

    2003-09-29

    A laser ablation/ionization mass spectrometer system is described for the direct analysis of solids, particles, and fibers. The system uses a quadrupole ion trap operated in an ion-storage (IS) mode, coupled with a reflectron time-of-flight mass spectrometer (TOF-MS). The sample is inserted radially into the ring electrode and an imaging system allows direct viewing and selected analysis of the sample. Measurements identified trace contaminants of Ag, Sn, and Sb in a Pb target with single laser-shot experiments. Resolution (m/{micro}m) of 1500 and detection limits of approximately 10 pg have been achieved with a single laser pulse. The system configuration and related operating principles for accurately measuring low concentrations of isotopes are described.

  2. Preparation and in situ Characterization of Surfaces Using Soft-Landing in a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

    SciTech Connect

    Alvarez, Jormarie; Cooks, Robert G.; Barlow, Stephan E.; Gaspar, Dan J.; Futrell, Jean H.; Laskin, Julia

    2005-06-01

    Mass-selected peptide ions produced by electrospray ionization were deposited onto fluorinated self-assembled monolayer surfaces (FSAM) surfaces by soft-landing using a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially designed for studying interactions of large ions with surfaces. Analysis of the modified surface was performed in situ by combining 2 keV Cs+ secondary ion mass spectrometry with FT-ICR detection of the sputtered ions (FT-ICR-SIMS). Regardless of the initial charge state of the precursor ion, the SIMS mass spectra included singly-protonated peptide fragment ions and peaks characteristic of the surfaces in all cases. In some experiments multiply-protonated peptide ions and [M+Au]+ ions were also observed upon SIMS analysis of modified surfaces. For comparison with the in situ analysis of the modified surfaces, ex situ analysis of some of the modified surfaces was performed by 25 kV Ga+ time of flight ? secondary ion mass spectrometry (ToF-SIMS). The ex situ analysis demonstrated that a significant number of soft-landed peptide ions remain charged on the surface even when exposed to air for several hours after deposition. Charge retention of soft-landed ions dramatically increases the ion yields obtained during SIMS analysis very sensitive detection of deposited material at less than 1% of monolayer coverage. Accumulation of charged species on the surface undergoes saturation due to Coulomb repulsion between charges at close to 30% coverage. We estimated that close to 1 ng of peptide could be deposited on the spot area of 4 mm2 of the FSAM surface without reaching saturation.

  3. The Pickup Ion Composition Spectrometer

    NASA Astrophysics Data System (ADS)

    Gilbert, Jason A.; Zurbuchen, Thomas H.; Battel, Steven

    2016-06-01

    Observations of newly ionized atoms that are picked up by the magnetic field in the expanding solar wind contain crucial information about the gas or dust compositions of their origins. The pickup ions (PUIs) are collected by plasma mass spectrometers and analyzed for their density, composition, and velocity distribution. In addition to measurements of PUIs from planetary sources, in situ measurements of interstellar gas have been made possible by spectrometers capable of differentiating between heavy ions of solar and interstellar origin. While important research has been done on these often singly charged ions, the instruments that have detected many of them were designed for the energy range and ionic charge states of the solar wind and energized particle populations, and not for pickup ions. An instrument optimized for the complete energy and time-of-flight characterization of pickup ions will unlock a wealth of data on these hitherto unobserved or unresolved PUI species. The Pickup Ion Composition Spectrometer (PICSpec) is one such instrument and can enable the next generation of pickup ion and isotopic mass composition measurements. By combining a large-gap time-of-flight-energy sensor with a -100 kV high-voltage power supply for ion acceleration, PUIs will not only be above the detection threshold of traditional solid-state energy detectors but also be resolved sufficiently in time of flight that isotopic composition can be determined. This technology will lead to a new generation of space composition instruments, optimized for measurements of both heliospheric and planetary pickup ions.

  4. Evaluating Multiplexed Quantitative Phosphopeptide Analysis on a Hybrid Quadrupole Mass Filter/Linear Ion Trap/Orbitrap Mass Spectrometer

    PubMed Central

    2015-01-01

    As a driver for many biological processes, phosphorylation remains an area of intense research interest. Advances in multiplexed quantitation utilizing isobaric tags (e.g., TMT and iTRAQ) have the potential to create a new paradigm in quantitative proteomics. New instrumentation and software are propelling these multiplexed workflows forward, which results in more accurate, sensitive, and reproducible quantitation across tens of thousands of phosphopeptides. This study assesses the performance of multiplexed quantitative phosphoproteomics on the Orbitrap Fusion mass spectrometer. Utilizing a two-phosphoproteome model of precursor ion interference, we assessed the accuracy of phosphopeptide quantitation across a variety of experimental approaches. These methods included the use of synchronous precursor selection (SPS) to enhance TMT reporter ion intensity and accuracy. We found that (i) ratio distortion remained a problem for phosphopeptide analysis in multiplexed quantitative workflows, (ii) ratio distortion can be overcome by the use of an SPS-MS3 scan, (iii) interfering ions generally possessed a different charge state than the target precursor, and (iv) selecting only the phosphate neutral loss peak (single notch) for the MS3 scan still provided accurate ratio measurements. Remarkably, these data suggest that the underlying cause of interference may not be due to coeluting and cofragmented peptides but instead from consistent, low level background fragmentation. Finally, as a proof-of-concept 10-plex experiment, we compared phosphopeptide levels from five murine brains to five livers. In total, the SPS-MS3 method quantified 38 247 phosphopeptides, corresponding to 11 000 phosphorylation sites. With 10 measurements recorded for each phosphopeptide, this equates to more than 628 000 binary comparisons collected in less than 48 h. PMID:25521595

  5. Development of a time-of-flight mass spectrometer combined with an ion-attachment method for multicomponent gas analysis

    NASA Astrophysics Data System (ADS)

    Takaya, Kazunari; Takahashi, Karin; Deguchi, Yuri; Sakai, Yasuhiro

    2014-10-01

    We developed a new mass spectrometer that can analyse multicomponent gases without fragmentation. This is essentially a time-of-flight (TOF) mass analyser in which the ion attachment method is used for ionisation. The method using this new device is referred to as “time-of-flight analysis in combination with ion-attachment” (TOFIA). TOFIA has the capability to analyse breath gas in about 10 min using the radio-frequency (RF) ion-guiding method and a multichannel scaler (MCS). The mass resolution of the trial device was unsatisfactory, but the device can be greatly improved in the future. We successfully analysed exhaled breath gases related to diseases, including ammonia, acetone, and isoprene gases. We expect that the TOFIA device developed in this work will contribute significantly to studies on the relationship between breath gas and health.

  6. Observations of plasma dynamics in the coma of P/Halley by the Giotto Ion Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Goldstein, B. E.; Goldstein, R.; Neugebauer, M.; Fuselier, S. A.; Shelley, E. G.; Balsiger, H.; Kettmann, G.; Ip, W.-H.; Rosenbauer, H.; Schwenn, R.

    1991-01-01

    Observations in the coma of P/Halley by the Giotto Ion Mass Spectrometer (IMS) are reported. The High Energy Range Spectrometer (HERS) of the IMS obtained measurements of protons and alpha particles from the far upstream region to the near ionopause region and of ions from mass 12 to 32 at distances of about 250,000 to 40,000 km from the nucleus. Plasma parameters from the High Intensity Spectrometer (HIS) of the IMS obtained between 150,000 to 5000 km from the nucleus are also discussed. The distribution functions of water group ions (water group will be used to refer to ions of 16 to 18 m/q, where m is in AMU and q is in unit charges) are observed to be spherically symmetric in velocity space, indicating strong pitch angle scattering. The discontinuity known as the magnetic pile-up boundary (MPB) is apparent only in proton, alpha, and magnetometer data, indicating that it is a tangential discontinuity of solar wind origin. HERS observations show no significant change in the properties of the heavy ions across the MPB. A comparison of the observations to an MHD model is made. The plasma flow directions at all distances greater than 30,000 km from the nucleus are in agreement with MHD calculations. However, despite the agreement in flow direction, within 200,000 km of the nucleus the magnitude of the velocity is lower than predicted by the MHD model and the density is much larger (a factor of 4). Within 30,000 km of the nucleus there are large theoretical differences between the MHD model flow calculations for the plane containing the magnetic field and for the plane perpendicular to the magnetic field. The observations agreed much better with the pattern calculated for the plane perpendicular to the magnetic field. The data obtained by the High Energy Range Spectrometer (HERS) of the IMS that are published herein were provided to the International Halley Watch archive.

  7. A Quadrupole Ion Trap Mass Spectrometer for Quantitative Analysis of Nitrogen-Purged Compartments within the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Ottens, Andrew K.; Griffin, Timothy P.; Helms, William R.; Yost, Richard A.; Steinrock, T. (Technical Monitor)

    2001-01-01

    To enter orbit, the Space Shuttle burns 1.8 million liters of liquid hydrogen combined with 0.8 million liters of liquid oxygen through three rocket engines mounted in the aft. NASA monitors the nitrogen-purged aft compartment for increased levels of hydrogen or oxygen in order to detect and determine the severity of a cryogenic fuel leak. Current monitoring is accomplished with a group of mass spectrometer systems located as much as 400 feet away from the Shuttle. It can take up to 45 seconds for gas to reach the mass spectrometer, which precludes monitoring for leaks in the final moments before liftoff (the orbiter engines are started at T-00:06 seconds). To remedy the situation, NASA is developing a small rugged mass spectrometer to be used as point-sensors around the Space Shuttle. As part of this project, numerous mass analyzer technologies are being investigated. Presented here are the preliminary results for one such technology, quadrupole ion trap mass spectrometry (QITMS). A compact QITMS system has been developed in-house at the University of Florida for monitoring trace levels of four primary gases, hydrogen, helium, oxygen, and argon, all in a nitrogen background. Since commercially available QITMS systems are incapable of mass analysis at m/z(exp 2), the home-built system is preferred for the evaluation of QITMS technology.

  8. Lunar and Asteroid Composition Using a Remote Secondary Ion Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Elphic, R. C.; Funsten, H. O.; Barraclough, B. L.; Mccomas, D. J.; Nordholt, J. E.

    1992-01-01

    Laboratory experiments simulating solar wind sputtering of lunar surface materials have shown that solar wind protons sputter secondary ions in sufficient numbers to be measured from low-altitude lunar orbit. Secondary ions of Na, Mg, Al, Si, K, Ca, Mn, Ti, and Fe have been observed sputtered from sample simulants of mare and highland soils. While solar wind ions are hundreds of times less efficient than those used in standard secondary ion mass spectrometry, secondary ion fluxes expected at the Moon under normal solar wind conditions range from approximately 10 to greater than 10(exp 4) ions cm(sup -2)s(sup -1), depending on species. These secondary ion fluxes depend both on concentration in the soil and on probability of ionization; yields of easily ionized elements such as K and Na are relatively much greater than those for the more electronegative elements and compounds. Once these ions leave the surface, they are subject to acceleration by local electric and magnetic fields. For typical solar wind conditions, secondary ions can be accelerated to an orbital observing location. The same is true for atmospheric atoms and molecules that are photoionized by solar EUV. The instrument to detect, identify, and map secondary ions sputtered from the lunar surface and photoions arising from the tenuous atmosphere is discussed.

  9. Improved atmospheric trace gas measurements with an aircraft-based tandem mass spectrometer: Ion identification by mass-selected fragmentation studies

    NASA Astrophysics Data System (ADS)

    Reiner, Thomas; MöHler, Ottmar; Arnold, Frank

    1998-12-01

    We have built and employed an aircraft-borne triple quadrupole mass spectrometer (TQMS) for fragmentation studies of mass-selected ions in the upper troposphere and lower stratosphere. The fragmentation studies included both ambient and artificially produced ions relevant for the measurement of atmospheric trace gases by ion molecule reaction mass spectrometry (IMRMS) and led to an unambiguous identification of the chemical composition of important ions used for IMRMS measurements. Among these are the product ions of ion molecule reactions of CO3-(H2O)n and H3O+(H2O)n ions with HNO3, SO2, acetone, HCN, and methyl cyanide. These reactions have been studied in the laboratory, and ions having the same masses as the expected product ions have been previously observed in atmospheric IMRMS spectra. The present fragmentation studies are the first to actually identify the chemical composition of these ions during aircraft measurements in the upper troposphere and lower stratosphere and demonstrate that these ions can reliably be used for atmospheric trace gas measurements. Furthermore, the fragmentation studies gave indications for the existence and the possible identification of previously unknown ions. Among these the tentative identification of CO3-H2O2 offers the possibility for sensitive measurements of H2O2 by IMRMS. The fragmentation studies were accompanied by IMRMS measurements of atmospheric trace gases using the TQMS. Altitude profiles of HNO3, SO2, and lower limits for H2O2 are shown.

  10. Finnigan ion trap mass spectrometer detection limits and thermal energy analyzer interface status report and present capabilities

    SciTech Connect

    Alcaraz, A.; Andresen, B.; Martin, W.

    1990-10-18

    A new Finnigan ion trap mass spectrometer was purchased and installed at LLNL. Over a period of several months the instrument was tested under a variety of conditions utilizing a capillary gas chromatography interface which allowed separated organic compounds to be carried directly into the ion source of the mass spectrometer. This direct interface allowed maximum analytical sensitivity. A variety of critical tests were performed in order to optimize the sensitivity of the system under a variety of analysis conditions. These tests altered the critical time cycles of the ionization, ion trapping, and detection. Various carrier gas pressures were also employed in order to ascertain the overall sensitivity of the instrument. In addition we have also interfaced a thermal energy analyzer (TEA) to the gas chromatograph in order to simultaneously detect volatile nitrogen containing compounds while mass spectral data is being acquired. This is the first application at this laboratory of simultaneous ultra-trace detections while utilizing two orthogonal analytical techniques. In particular, explosive-related compound and/or residues are of interest to the general community in water, soil and gas sampler. In this paper are highlighted a few examples of the analytical power of this new GC-TEA-ITMS technology.

  11. Early Observations of the Upper Atmosphere and Ionosphere of Mars by MAVEN’s Neutral Gas and Ion Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Benna, Mehdi; Mahaffy, Paul R.; Elrod, Meredith

    2015-04-01

    The Neutral Gas and Ion Mass Spectrometer (NGIMS) of the Mars Atmosphere and Volatile Evolution (MAVEN) Mission is designed to characterize the source region of escaping atoms in the upper atmosphere and ionosphere of Mars. The NGIMS instrument is a quadrupole analyzer with a mass rang of 2-150 Da. It utilizes a dual ion source in order to measure both surface reactive neutrals (using the Open Source Neutral mode - OSN), inert neutrals (using the Closed Source Neutral mode - CSN), and thermal ions (using the Open Source Ion mode - OSI) at altitudes below 500 km.In the first few months of the MAVEN mission, NGIMS alternated on sequential orbits between measurement sequences that focus on fully characterizing neutral species (using the CSN/OSN modes) and ions (using the CSN/OSI modes). The collected data revealed the substantial structure present in both neutral and ion densities with spatial scales of hundreds of kilometers along the spacecraft track. The data also brought to light the sharp contrast between the day side and night side atmospheric profiles of neutrals and ions in both total density and relative abundance.

  12. A satellite-borne ion mass spectrometer for the energy range 0 to 16 keV

    NASA Technical Reports Server (NTRS)

    Balsiger, H.; Eberhardt, P.; Geiss, J.; Ghielmetti, A.; Walker, H. P.; Young, D. T.; Loidl, H.; Rosenbauer, H.

    1976-01-01

    The Ion Composition Experiment (ICE) on GEOS represents the first comprehensive attempt to measure the positive ion composition at high altitudes in the magnetosphere. Due to the heterogeneous nature of the magnetospheric plasma a novel mass spectrometer has been developed to cover the mass per charge range from H-1(+) to beyond Ba-138(+) and the energy per charge range from 0 to 16 keV/e. The ICE consists primarily of a cylindrical electrostatic analyzer followed by a curved analyzer incorporating crossed magnetic and electric fields. This combination has limited angular and energy focusing properties, but it maintains a mass resolution of about 4 over a wide range in energy and mass, sufficient for the objectives of measuring plasmas of both solar and terrestrial origin. High sensitivity and low background should allow measurements of rarer ion constituents down to flux levels of 0.01 ions/sq cm sec ster eV. A sophisticated electronics combined with powerful ground computer and telecommand systems allow for very efficient scanning of the mass-energy space.

  13. Mars Organic Molecule Analyzer (MOMA) Mass Spectrometer Flight Model and Future Ion Trap-Based Planetary Instruments

    NASA Astrophysics Data System (ADS)

    Brinckerhoff, W. B.; van Amerom, F. H. W.; Danell, R.; Pinnick, V. T.; Arevalo, R. D., Jr.; Li, X.; Grubisic, A.; Getty, S.; Hovmand, L.; Mahaffy, P. R.

    2015-12-01

    The Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars rover will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. MOMA combines pyrolysis gas chromatography mass spectrometry (GCMS) of bulk powder samples and Mars ambient laser desorption mass spectrometry (LDMS) surface analysis, using a single ion trap MS. This dual source design enables MOMA to detect compounds over a wide range of molecular weights and volatilities. The structure of any detected organics may be further examined using MOMA's tandem mass spectrometry (MS/MS) mode. The flight model (FM) ion trap sensor and electronics have been assembled under the extremely clean and sterile conditions required by ExoMars, and have met or exceeded all performance specifications during initial functional tests. After Mars ambient thermal cycling and calibration, the FM will be delivered as a subsystem of MOMA to rover integration in mid-2016. There MOMA will join complementary rover instruments such as the Raman and MicrOmega spectrometers designed to analyze common drill samples. Following the MOMA design, linear ion trap mass spectrometer (LITMS)-based instruments are under development for future missions. LITMS adds enhanced capabilities such as precision (point-by-point) analysis of drill cores, negative ion detection, a wider mass range, and higher temperature pyrolysis with precision evolved gas analysis, while remaining highly compact and robust. Each of the capabilities of LITMS has been demonstrated on breadboard hardware. The next phase will realize an end-to-end brassboard at flight scale that will meet stringent technology readiness level (TRL) 6 criteria, indicating readiness for development toward missions to Mars, comets, asteroids, outer solar system moons, and beyond.

  14. Photo ion spectrometer

    DOEpatents

    Gruen, Dieter M.; Young, Charles E.; Pellin, Michael J.

    1989-01-01

    A method and apparatus for extracting for quantitative analysis ions of selected atomic components of a sample. A lens system is configured to provide a slowly diminishing field region for a volume containing the selected atomic components, enabling accurate energy analysis of ions generated in the slowly diminishing field region. The lens system also enables focusing on a sample of a charged particle beam, such as an ion beam, along a path length perpendicular to the sample and extraction of the charged particles along a path length also perpendicular to the sample. Improvement of signal to noise ratio is achieved by laser excitation of ions to selected autoionization states before carrying out quantitative analysis. Accurate energy analysis of energetic charged particles is assured by using a preselected resistive thick film configuration disposed on an insulator substrate for generating predetermined electric field boundary conditions to achieve for analysis the required electric field potential. The spectrometer also is applicable in the fields of SIMS, ISS and electron spectroscopy.

  15. Photo ion spectrometer

    DOEpatents

    Gruen, D.M.; Young, C.E.; Pellin, M.J.

    1989-08-08

    A method and apparatus are described for extracting for quantitative analysis ions of selected atomic components of a sample. A lens system is configured to provide a slowly diminishing field region for a volume containing the selected atomic components, enabling accurate energy analysis of ions generated in the slowly diminishing field region. The lens system also enables focusing on a sample of a charged particle beam, such as an ion beam, along a path length perpendicular to the sample and extraction of the charged particles along a path length also perpendicular to the sample. Improvement of signal to noise ratio is achieved by laser excitation of ions to selected auto-ionization states before carrying out quantitative analysis. Accurate energy analysis of energetic charged particles is assured by using a preselected resistive thick film configuration disposed on an insulator substrate for generating predetermined electric field boundary conditions to achieve for analysis the required electric field potential. The spectrometer also is applicable in the fields of SIMS, ISS and electron spectroscopy. 8 figs.

  16. The charge-energy-mass spectrometer for 0.3-300 keV/e ions on the AMPTE CCE

    NASA Technical Reports Server (NTRS)

    Gloeckler, G.; Ipavich, F. M.; Hamilton, D. C.; Lundgren, R. A.; Studemann, W.; Wilken, B.; Kremser, G.; Hovestadt, D.; Gliem, F.; Rieck, W.

    1985-01-01

    The charge-energy-mass (CHEM) spectrometer on the Charge Composition Explorer (CCE) has the function to measure the energy spectra, pitch-angle distributions, and ionization states of ions in the earth's magnetosphere and magnetosheath in the energy range from 0.3 to 300 keV/charge with a time resolution of less than 1 min. The obtained data will provide essential information on outstanding problems related to ion sources and dynamical processes of space plasmas and of suprathermal ions. A description of the CHEM experiment is given, taking into account the principle of operation, the sensor, the electronics, instrument characteristics, specifications, and requirements. Questions of postlaunch performance are also discussed.

  17. Investigation of hydrogen and helium pumping by sputter ion pumps for Jupiter and outer planets mass spectrometer

    NASA Technical Reports Server (NTRS)

    Scott, B. W.

    1977-01-01

    The phenomena of ion pumping is reviewed with emphasis on the pumping mechanism for hydrogen and helium. The experimental tests measure the performance of a small, flight proven ion pump which has a nominal four liter/second pumping speed for air. The speed of this pump for hydrogen and helium, and for hydrogen/helium mixes, is presented with particular detail regarding the time dependence. Pump test results are related to anticipated performance of the mass spectrometer by the pumping speeds for the gases to the partial pressure in the ion source. From this analysis, the pump specifications are quantified in terms of mission goals and in terms of observed pumping speeds for the various gases, load levels, and time periods.

  18. Development of an Ion Mass Spectrometer and Sounding Rocket System for D-Region Cluster-Ion Measurements.

    DTIC Science & Technology

    1982-01-27

    IbM. DI NbOl Preface The preparation of this report was possible only because of the manifold extra contributions of the following: R. Sukys ...is to assure tracking of their ratios as a function of environment. Corning CYR glass capacitors are specified. 8. Rochefort, J.S., and Sukys , R. (1978...A Digital Control Unit for a Rocket- borne Quadrupole Mass Spectrometer, AFGL-TR-78-0106, ADA 057251. 9. Rochefort, J. S., and Sukys , R. (1978

  19. Non-thermal internal energy distribution of ions observed in an electrospray source interfaced with a sector mass spectrometer.

    PubMed

    Rondeau, David; Galland, Nicolas; Zins, Emilie-Laure; Pepe, Claude; Drahos, László; Vékey, Károly

    2011-02-01

    The internal energy distribution P(E(int)) of ions emitted in an electrospray (ESI) source interfaced with a sector mass spectrometer is evaluated by using the experimental survival yield (SY) method including the kinetic shift. This method is based on the relationship between the degree of fragmentation of an ion and its amount of internal energy and uses benzylpyridinium cations due to their simple fragmentation scheme. Quantum chemical calculations are performed, namely at G3(MP2)//B3LYP and QCISD/MP2 levels of theory. The results show that the internal energy distribution of the ions emitted in the ESI source interfaced with a sector analyzer is very narrow. The MassKinetics software is used to confirm these observations. The P(E(int)) is the parameter that allows to fit the experimental SY of each substituted benzylpyridinium cation with theoretical mass spectra generated by the MassKinetics software. The resulting internal energy distributions are similar to the ones obtained with the experimental SY method. This indicates that in the present experimental conditions, P(E(int)) cannot be compared with a 'thermal-like' Boltzmann distribution. In addition, it appears that with the sector analyzer, increasing the collision energy in the first pumping stage of the ESI source does not correspond to a warm-up of the produced ions.

  20. Dynamic collision-induced dissociation of peptides in a quadrupole ion trap mass spectrometer.

    PubMed

    Collin, Olivier L; Beier, Matthias; Jackson, Glen P

    2007-07-15

    The fragmentation of natural peptides using dynamic collision-induced dissociation (DCID), a novel fragmentation method for quadrupole ion traps, is demonstrated. Using leucine enkephalin as a diagnostic molecule, the fragmentation efficiencies and energetics of DCID are compared with other methods of collisional activation in ion traps such as conventional on-resonance excitation and high-amplitude short-time excitation (HASTE). A typical fragmentation efficiency of approximately 20% is achieved for DCID, which is significantly lower than conventional CID (maximum near 80%). Tandem mass spectra of two other peptides, substance P and oxidized insulin alpha-chain, demonstrate that product ion spectra for DCID are comparable to conventional or HASTE CID. Because DCID achieves fragmentation during the standard mass acquisition scan, no extra time is necessary for on-resonance excitation or product ion collection, so analysis times are reduced by a minimum of 10-15% depending on the scanning conditions. DCID therefore offers more tandem mass spectra per second than conventional methods of collisional activation, which could be highly advantageous for bottom-up proteomics separations.

  1. Development of portable mass spectrometer with electron cyclotron resonance ion source for detection of chemical warfare agents in air.

    PubMed

    Urabe, Tatsuya; Takahashi, Kazuya; Kitagawa, Michiko; Sato, Takafumi; Kondo, Tomohide; Enomoto, Shuichi; Kidera, Masanori; Seto, Yasuo

    2014-01-01

    A portable mass spectrometer with an electron cyclotron resonance ion source (miniECRIS-MS) was developed. It was used for in situ monitoring of trace amounts of chemical warfare agents (CWAs) in atmospheric air. Instrumental construction and parameters were optimized to realize a fast response, high sensitivity, and a small body size. Three types of CWAs, i.e., phosgene, mustard gas, and hydrogen cyanide were examined to check if the mass spectrometer was able to detect characteristic elements and atomic groups. From the results, it was found that CWAs were effectively ionized in the miniECRIS-MS, and their specific signals could be discerned over the background signals of air. In phosgene, the signals of the 35Cl+ and 37Cl+ ions were clearly observed with high dose-response relationships in the parts-per-billion level, which could lead to the quantitative on-site analysis of CWAs. A parts-per-million level of mustard gas, which was far lower than its lethal dosage (LCt50), was successfully detected with a high signal-stability of the plasma ion source. It was also found that the chemical forms of CWAs ionized in the plasma, i.e., monoatomic ions, fragment ions, and molecular ions, could be detected, thereby enabling the effective identification of the target CWAs. Despite the disadvantages associated with miniaturization, the overall performance (sensitivity and response time) of the miniECRIS-MS in detecting CWAs exceeded those of sector-type ECRIS-MS, showing its potential for on-site detection in the future.

  2. Photo ion spectrometer

    DOEpatents

    Gruen, D.M.; Young, C.E.; Pellin, M.J.

    1989-12-26

    A charged particle spectrometer is described for performing ultrasensitive quantitative analysis of selected atomic components removed from a sample. Significant improvements in performing energy and angular refocusing spectroscopy are accomplished by means of a two dimensional structure for generating predetermined electromagnetic field boundary conditions. Both resonance and non-resonance ionization of selected neutral atomic components allow accumulation of increased chemical information. A multiplexed operation between a SIMS mode and a neutral atomic component ionization mode with EARTOF analysis enables comparison of chemical information from secondary ions and neutral atomic components removed from the sample. An electronic system is described for switching high level signals, such as SIMS signals, directly to a transient recorder and through a charge amplifier to the transient recorder for a low level signal pulse counting mode, such as for a neutral atomic component ionization mode. 12 figs.

  3. Photo ion spectrometer

    DOEpatents

    Gruen, Dieter M.; Young, Charles E.; Pellin, Michael J.

    1989-01-01

    A charged particle spectrometer for performing ultrasensitive quantitative analysis of selected atomic components removed from a sample. Significant improvements in performing energy and angular refocusing spectroscopy are accomplished by means of a two dimensional structure for generating predetermined electromagnetic field boundary conditions. Both resonance and non-resonance ionization of selected neutral atomic components allow accumulation of increased chemical information. A multiplexed operation between a SIMS mode and a neutral atomic component ionization mode with EARTOF analysis enables comparison of chemical information from secondary ions and neutral atomic components removed from the sample. An electronic system is described for switching high level signals, such as SIMS signals, directly to a transient recorder and through a charge amplifier to the transient recorder for a low level signal pulse counting mode, such as for a neutral atomic component ionization mode.

  4. First spatial separation of a heavy ion isomeric beam with a multiple-reflection time-of-flight mass spectrometer

    NASA Astrophysics Data System (ADS)

    Dickel, T.; Plaß, W. R.; Ayet San Andres, S.; Ebert, J.; Geissel, H.; Haettner, E.; Hornung, C.; Miskun, I.; Pietri, S.; Purushothaman, S.; Reiter, M. P.; Rink, A.-K.; Scheidenberger, C.; Weick, H.; Dendooven, P.; Diwisch, M.; Greiner, F.; Heiße, F.; Knöbel, R.; Lippert, W.; Moore, I. D.; Pohjalainen, I.; Prochazka, A.; Ranjan, M.; Takechi, M.; Winfield, J. S.; Xu, X.

    2015-05-01

    211Po ions in the ground and isomeric states were produced via 238U projectile fragmentation at 1000 MeV/u. The 211Po ions were spatially separated in flight from the primary beam and other reaction products by the fragment separator FRS. The ions were energy-bunched, slowed-down and thermalized in a gas-filled cryogenic stopping cell (CSC). They were then extracted from the CSC and injected into a high-resolution multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS). The excitation energy of the isomer and, for the first time, the isomeric-to-ground state ratio were determined from the measured mass spectrum. In the subsequent experimental step, the isomers were spatially separated from the ions in the ground state by an ion deflector and finally collected with a silicon detector for decay spectroscopy. This pioneering experimental result opens up unique perspectives for isomer-resolved studies. With this versatile experimental method new isomers with half-lives longer than a few milliseconds can be discovered and their decay properties can be measured with highest sensitivity and selectivity. These experiments can be extended to studies with isomeric beams in nuclear reactions.

  5. New method for comprehensive detection of chemical warfare agents using an electron-cyclotron-resonance ion-source mass spectrometer.

    PubMed

    Kidera, Masanori; Seto, Yasuo; Takahashi, Kazuya; Enomoto, Shuichi; Kishi, Shintaro; Makita, Mika; Nagamatsu, Tsuyoshi; Tanaka, Tatsuhiko; Toda, Masayoshi

    2011-03-01

    We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN(+) using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents.

  6. New method for comprehensive detection of chemical warfare agents using an electron-cyclotron-resonance ion-source mass spectrometer

    NASA Astrophysics Data System (ADS)

    Kidera, Masanori; Seto, Yasuo; Takahashi, Kazuya; Enomoto, Shuichi; Kishi, Shintaro; Makita, Mika; Nagamatsu, Tsuyoshi; Tanaka, Tatsuhiko; Toda, Masayoshi

    2011-03-01

    We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN + using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents.

  7. Mass spectrometric characterization of a high-field asymmetric waveform ion mobility spectrometer

    NASA Astrophysics Data System (ADS)

    Purves, Randy W.; Guevremont, Roger; Day, Stephen; Pipich, Charles W.; Matyjaszczyk, Matthew S.

    1998-12-01

    Ion mobility spectrometry (IMS) has become an important method for the detection of many compounds because of its high sensitivity and amenability to miniaturization for field-portable monitoring; applications include detection of narcotics, explosives, and chemical warfare agents. High-field asymmetric waveform ion mobility spectrometry (FAIMS) differs from IMS in that the electric fields are applied using a high-frequency periodic asymmetric waveform, rather than a dc voltage. Furthermore, in FAIMS the compounds are separated by the difference in the mobility of ions at high electric field relative to low field, rather than by compound to compound differences in mobility at low electric field (IMS). We report here the first cylindrical-geometry-FAIMS interface with mass spectrometry (FAIMS-MS) and the MS identification of the peaks observed in a FAIMS compensation voltage (CV) spectrum. Using both an electrometer-based-FAIMS (FAIMS-E) and FAIMS-MS, several variables that affect the sensitivity of ion detection were examined for two (polarity reversed) asymmetric waveforms (modes 1 and 2) each of which yields a unique spectrum. An increase in the dispersion voltage (DV) was found to improve the sensitivity and separation observed in the FAIMS CV spectrum. This increase in sensitivity and the unexpected dissimilarity in modes 1 and 2 suggest that atmospheric pressure ion focusing is occurring in the FAIMS analyzer. The sensitivity and peak locations in the CV spectra were affected by temperature, gas flow rates, operating pressure, and analyte concentration.

  8. Large-scale collision cross-section profiling on a travelling wave ion mobility mass spectrometer

    PubMed Central

    Lietz, Christopher B.; Yu, Qing; Li, Lingjun

    2014-01-01

    Ion mobility (IM) is a gas-phase electrophoretic method that separates ions according to charge and ion-neutral collision cross-section (CCS). Herein, we attempt to apply a travelling wave (TW) IM polyalanine calibration method to shotgun proteomics and create a large peptide CCS database. Mass spectrometry methods that utilize IM, such as HDMSE, often use high transmission voltages for sensitive analysis. However, polyalanine calibration has only been demonstrated with low voltage transmission used to prevent gas-phase activation. If polyalanine ions change conformation under higher transmission voltages used for HDMSE, the calibration may no longer be valid. Thus, we aimed to characterize the accuracy of calibration and CCS measurement under high transmission voltages on a TW IM instrument using the polyalanine calibration method and found that the additional error was not significant. We also evaluated the potential error introduced by liquid chromatography (LC)-HDMSE analysis, and found it to be insignificant as well, validating the calibration method. Finally, we demonstrated the utility of building a large-population peptide CCS database by investigating the effects of terminal lysine position, via LysC or LysN digestion, on the formation of two structural sub-families formed by triply charged ions. PMID:24845359

  9. Improvement of the duty cycle of an orthogonal acceleration time-of-flight mass spectrometer using ion gates.

    PubMed

    Brenton, A G; Krastev, T; Rousell, D J; Kennedy, M A; Craze, A S; Williams, C M

    2007-01-01

    A method to control the duty cycle of a time-of-flight mass spectrometer is described. The method relies on one or more ion gates placed in the beam path that have the function to transmit or stop the beam. These ion gates can switch from the open state to the closed state in tens of nanoseconds and effectively select portions of the mass range. The method is useful in circumstances where recording the complete mass spectrum is not an essential requirement, for example, in the analysis of known compounds where sensitivity and speed of operation are more important. It will be of benefit for applications in separation sciences with techniques involving fast chromatographic separations, where hundreds of mass spectra may be required per second. In such circumstances analytical identification may require only a limited number of masses (or mass regions) to be continuously monitored. Improvement of the duty cycle is particularly important for orthogonal-acceleration time-of-flight (oa-TOF) mass spectrometry instruments whose performance suffers from a low duty cycle. The duty cycle is not a constant for an instrument design but is a mass-dependent function and is least for smaller masses. The method described here is capable of raising the duty cycle to 100%. A theory is developed for one or more ion gate arrangements, for both linear- and reflectron-TOF systems. For a two-gate system the relationship between the positions of the first and second gates is described by a '2/3 rule'. Experimental results are shown for one-gate and two-gate operation, both in linear and in reflectron modes of operation, on an oa-TOF system built in-house.

  10. Identification of epoxide functionalities in protonated monofunctional analytes by using ion/molecule reactions and collision-activated dissociation in different ion trap tandem mass spectrometers.

    PubMed

    Eismin, Ryan J; Fu, Mingkun; Yem, Sonoeun; Widjaja, Fanny; Kenttämaa, Hilkka I

    2012-01-01

    A mass spectrometric method has been delineated for the identification of the epoxide functionalities in unknown monofunctional analytes. This method utilizes gas-phase ion/molecule reactions of protonated analytes with neutral trimethyl borate (TMB) followed by collision-activated dissociation (CAD) in an ion trapping mass spectrometer (tested for a Fourier-transform ion cyclotron resonance and a linear quadrupole ion trap). The ion/molecule reaction involves proton transfer from the protonated analyte to TMB, followed by addition of the analyte to TMB and elimination of methanol. Based on literature, this reaction allows the general identification of oxygen-containing analytes. Vinyl and phenyl epoxides can be differentiated from other oxygen-containing analytes, including other epoxides, based on the loss of a second methanol molecule upon CAD of the addition/methanol elimination product. The only other analytes found to undergo this elimination are some amides but they also lose O = B-R (R = group bound to carbonyl), which allows their identification. On the other hand, other epoxides can be differentiated from vinyl and phenyl epoxides and from other monofunctional analytes based on the loss of (CH(3)O)(2)BOH or formation of protonated (CH(3)O)(2)BOH upon CAD of the addition/methanol elimination product. For propylene oxide and 2,3-dimethyloxirane, the (CH(3)O)(2)BOH fragment is more basic than the hydrocarbon fragment, and the diagnostic ion (CH(3)O)(2)BOH (2) (+) is formed. These reactions involve opening of the epoxide ring. The only other analytes found to undergo (CH(3)O)(2)BOH elimination are carboxylic acids, but they can be differentiated from the rest based on several published ion/molecule reaction methods. Similar results were obtained in the Fourier-transform ion cyclotron resonance and linear quadrupole ion trap mass spectrometer.

  11. Giotto-IMS observations of ion flow velocities and temperatures outside the contact surface of Comet Halley. [Ion Mass Spectrometer (IMS)

    NASA Technical Reports Server (NTRS)

    Goldstein, B. E.; Neugebauer, M.; Balsiger, H.; Drake, J.; Fuselier, S. A.; Goldstein, R.; Ip, WING-H.; Rettenmund, U.; Rosenbauer, H.; Schwenn, R.

    1986-01-01

    Fluid parameters for He(++) ions obtained from the Giotto ion mass spectrometer are presented. Proton densities and velocities and thermal speeds of protons, alpha particles, and heavy ions in the hour before closest approach are discussed. A region of enhanced He(++) ion densities, and velocity, and decreased temperature is observed from 20:26 to 21:45. Sharp decreases in the proton density are observed at 23:30 and at 23:41. There is a relative flow velocity between alpha particles and oxygen ions of 30 km/sec during a period from 22:55 to 23:30; the difference in flow velocity is less than the experimental uncertainities. The flow properties of protons observed during this period are also discussed.

  12. Gas Chromatic Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Wey, Chowen

    1995-01-01

    Gas chromatograph/mass spectrometer (GC/MS) used to measure and identify combustion species present in trace concentration. Advanced extractive diagnostic method measures to parts per billion (PPB), as well as differentiates between different types of hydrocarbons. Applicable for petrochemical, waste incinerator, diesel transporation, and electric utility companies in accurately monitoring types of hydrocarbon emissions generated by fuel combustion, in order to meet stricter environmental requirements. Other potential applications include manufacturing processes requiring precise detection of toxic gaseous chemicals, biomedical applications requiring precise identification of accumulative gaseous species, and gas utility operations requiring high-sensitivity leak detection.

  13. Signal generator exciting an electromagnetic field for ion beam transport to the vacuum chamber of a mass spectrometer

    NASA Astrophysics Data System (ADS)

    Tubol'tsev, Yu. V.; Kogan, V. T.; Bogdanov, A. A.; Chichagov, Yu. V.; Antonov, A. S.

    2015-02-01

    A high-voltage high-frequency signal generator is described that excites an electric field for ion beam transport from an ion source to the vacuum chamber of a mass spectrometer. Excitation signals to the number of two are high-frequency sine-wave out-of-phase signals with the same amplitudes. The amplitude and phase of the signals vary from 20 to 100 V and from 10 kHz to 1 MHz, respectively. The generator also produces a controlled bias voltage in the interval 50-200 V. The frequency and amplitude of the signals, as well as the bias voltage, are computer-controlled via the USB interface.

  14. Orbitrap for ILMA: Ion Laser Mass Analyser. A Mass-Spectrometer for In-Situ Characterization of a Near Earth Object (NEO)

    NASA Astrophysics Data System (ADS)

    Thissen, Roland; Thissen, R.; Arezki, B.; Berthelier, J. J.; Bouabdellah, A.; Boukrara, A.; Briois, C.; Carrasco, N.; Gilbert, P.; Engrand, C.; Grand, N.; Hilchenbach, M.; Krüger, H.; Makarov, A.; Pennanech, C.; Puget, P.; Quirico, E.; Szopa, C.; Thirkell, L.; Zapf, P.; Cottin, H.

    Like other small bodies of the Solar System, asteroids are the remnants of planet formation. Their compositions are inherited from the Solar Nebula at the time of planetesimal accretion into planets, 4.5 billion years ago. They are valuable objects to assess the physicochemical conditions prevailing at the time and place of their formation in the Solar Nebula. Among them, some are known to be rich in carbon and volatile species (including water), which suggests that they never underwent major heating and differentiation events. Their organic content is also of prime interest because the chemical evolution leading to life on Earth may have been initiated by the delivery of extraterrestrial organic compounds into primitive oceans. For these reasons, several space missions are currently considered by ESA and JAXA for a sample return mission to a primitive carbonaceous Near-Earth Object (NEO): MARCO POLO, HAYABUZA 2, etc... Their goal is to characterize a NEO at multiple scales via in-situ measurements by a science payload onboard an orbiter and a lander, and to bring samples back to Earth. ILMA is a concept for a new generation high resolution mass spectrometer, proposed to be part of a lander payload for in situ science. This instrument will be a Fourier Transform ion trap mass spectrometer using Laser Desorption and Ionization Mass Spectrometry (LDIMS) into a single platform. To this end, an Orbitrap mass analyser (developed by the Thermofisher Company) will be coupled to a laser source. The sample will be exposed to the laser beam producing desorbed ions which will be collected into the ion trap using the orbital trapping method. Ions will be stabilized in the trap by purely electrostatic quadro-logarithmic electrical fields and the detection undertaken by a non destructive measurement of the ion oscillation frequency inside the trap. Indeed, the trapped ions induce a periodic signal converted using Fourier Transform (FT) into an ultra-high mass resolution spectrum

  15. Accelerator mass spectrometer with ion selection in high-voltage terminal

    NASA Astrophysics Data System (ADS)

    Rastigeev, S. A.; Goncharov, A. D.; Klyuev, V. F.; Konstantinov, E. S.; Kutnyakova, L. A.; Parkhomchuk, V. V.; Petrozhitskii, A. V.; Frolov, A. R.

    2016-12-01

    The folded electrostatic tandem accelerator with ion selection in a high-voltage terminal is the basis of accelerator mass spectrometry (AMS) at the BINP. Additional features of the BINP AMS are the target based on magnesium vapors as a stripper without vacuum deterioration and a time-of-flight telescope with thin films for reliable ion identification. The acceleration complex demonstrates reliable operation in a mode of 1 MV with 50 Hz counting rate of 14C+3 radiocarbon for modern samples (14C/12C 1.2 × 10-12). The current state of the AMS has been considered and the experimental results of the radiocarbon concentration measurements in test samples have been presented.

  16. Analysis of environmental contaminates in hair using an ion trap mass spectrometer with a filtered noise field waveboard

    SciTech Connect

    Alcaraz, A.; Hulsey, S.S.; Frantz, C.E.; Andresen, B.D.

    1994-12-31

    A variety of methods have been established using mass spectrometry (MS) for the analysis of chemicals in hair. Much of this past work has been focused on the detection of drugs of abuse. Human hair has been analyzed either directly by probe distillation (DIP) with some preliminary clean-up using HPLC or solid phase extraction (SPE). However, established drug analysis methods do not apply for the detection of some environmental contaminates. In this study, the authors selected 2,4,6-trinitrotoluene (TNT) and malathion as the target compounds. In addition two types of hair samples were analyzed: (1) human hair fortified with either TNT or malathion and (2) hair from mice who ingested the same analytes. The analytical method was DIP-EI-MS/MS with an ion trap mass spectrometer equipped with a filtered noise field wave board.

  17. Development of a new ion mobility time-of-flight mass spectrometer

    SciTech Connect

    Ibrahim, Yehia M.; Baker, Erin S.; Danielson, William F.; Norheim, Randolph V.; Prior, David C.; Anderson, Gordon A.; Belov, Mikhail E.; Smith, Richard D.

    2015-02-01

    Complex samples require multidimensional measurements with high resolution for full characterization of biological and environmental systems. To address this challenge, we developed a drift tube-based ion mobility spectrometry-Orbitrap mass spectrometry (IMS-Orbitrap MS) platform. To circumvent the timing difference between the fast IMS separation and the slow Orbitrap MS acquisition, we utilized a dual gate and pseudorandom sequence to multiplex ions into the drift tube and Orbitrap. The instrument was designed to operate in signal averaging (SA), single multiplexing (SM) and double multiplexing (DM) IMS modes to fully optimize the signal-to-ratio of the measurements. For the SM measurements, a previously developed algorithm was used to reconstruct the IMS data, while a new algorithm was developed for the DM analyses. The new algorithm is a two-step process that first recovers the SM data from the encoded DM data and then decoded the SM data. The algorithm also performs multiple refining procedures in order to minimize the demultiplexing artifacts traditionally observed in such scheme. The new IMS-Orbitrap MS platform was demonstrated for the analysis of proteomic and petroleum samples, where the integration of IMS and high mass resolution proved essential for accurate assignment of molecular formulae.

  18. The charge-energy-mass spectrometer for 0.3-300 keV/e ions on the AMPTE CCE

    NASA Astrophysics Data System (ADS)

    Gloeckler, G.; Ipavich, F. M.; Studemann, W.; Wilken, B.; Hamilton, D. C.; Kremser, G.; Hovestadt, D.; Gliem, F.; Lundgren, R. A.; Rieck, W.; Tums, E. O.; Cain, J. C.; Masung, L. S.; Weiss, W.; Winterhof, P.

    1985-05-01

    The charge-energy-mass (CHEM) spectrometer on the Charge Composition Explorer (CCE) spacecraft is designed to measure the mass and charge-state compositions as well as the energy spectra and pitch-angle distributions of all major ions from H through Fe with energies from 0.3 to 300 keV/charge and a time resolution of less than 1 min in the Earth's magnetosphere and magnetosheath. It has the sensitivity and resolution to detect artificially injected Li ions. Complementing the hot-plasma composition experiment and the medium-energy particle analyzer, this experiment will provide essential information on outstanding problems related to dynamical processes of space plasmas and of suprathermal ions. The instrument uses a combination of electrostatic deflection, post acceleration, and time of flight versus energy measurements to determine the ionization state Q, mass M, and energy E of the ambient-ion population. Pitch angle and anisotropy measurements are made utilizing the spinning motion of the CCE spacecraft. Isotopes of hydrogen and helium are resolved as are individual elements up to neon and dominant elements up to iron. Because of the intrinsically low instrument background achieved by using fast coincidence techniques combined with electrostatic deflection, the instrument has a large dynamic range and can identify rare elements and ions even in the presence of high-intensity radiation background. To increase significantly the information returned from the experiment within the allocated telemetry, an intelligent on-board data system which is part of the CHEM instrument performs fast M versus M/Q classifications.

  19. Comprehensive Lipidome Analysis by Shotgun Lipidomics on a Hybrid Quadrupole-Orbitrap-Linear Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Almeida, Reinaldo; Pauling, Josch Konstantin; Sokol, Elena; Hannibal-Bach, Hans Kristian; Ejsing, Christer S.

    2015-01-01

    Here we report on the application of a novel shotgun lipidomics platform featuring an Orbitrap Fusion mass spectrometer equipped with an automated nanoelectrospray ion source. To assess the performance of the platform for in-depth lipidome analysis, we evaluated various instrument parameters, including its high resolution power unsurpassed by any other contemporary Orbitrap instrumentation, its dynamic quantification range and its efficacy for in-depth structural characterization of molecular lipid species by quadrupole-based higher-energy collisional dissociation (HCD), and ion trap-based resonant-excitation collision-induced dissociation (CID). This evaluation demonstrated that FTMS analysis with a resolution setting of 450,000 allows distinguishing isotopes from different lipid species and features a linear dynamic quantification range of at least four orders of magnitude. Evaluation of fragmentation analysis demonstrated that combined use of HCD and CID yields complementary fragment ions of molecular lipid species. To support global lipidome analysis, we designed a method, termed MSALL, featuring high resolution FTMS analysis for lipid quantification, and FTMS2 analysis using both HCD and CID and ITMS3 analysis utilizing dual CID for in-depth structural characterization of molecular glycerophospholipid species. The performance of the MSALL method was benchmarked in a comparative analysis of mouse cerebellum and hippocampus. This analysis demonstrated extensive lipidome quantification covering 311 lipid species encompassing 20 lipid classes, and identification of 202 distinct molecular glycerophospholipid species when applying a novel high confidence filtering strategy. The work presented here validates the performance of the Orbitrap Fusion mass spectrometer for in-depth lipidome analysis.

  20. Comprehensive lipidome analysis by shotgun lipidomics on a hybrid quadrupole-orbitrap-linear ion trap mass spectrometer.

    PubMed

    Almeida, Reinaldo; Pauling, Josch Konstantin; Sokol, Elena; Hannibal-Bach, Hans Kristian; Ejsing, Christer S

    2015-01-01

    Here we report on the application of a novel shotgun lipidomics platform featuring an Orbitrap Fusion mass spectrometer equipped with an automated nanoelectrospray ion source. To assess the performance of the platform for in-depth lipidome analysis, we evaluated various instrument parameters, including its high resolution power unsurpassed by any other contemporary Orbitrap instrumentation, its dynamic quantification range and its efficacy for in-depth structural characterization of molecular lipid species by quadrupole-based higher-energy collisional dissociation (HCD), and ion trap-based resonant-excitation collision-induced dissociation (CID). This evaluation demonstrated that FTMS analysis with a resolution setting of 450,000 allows distinguishing isotopes from different lipid species and features a linear dynamic quantification range of at least four orders of magnitude. Evaluation of fragmentation analysis demonstrated that combined use of HCD and CID yields complementary fragment ions of molecular lipid species. To support global lipidome analysis, we designed a method, termed MS(ALL), featuring high resolution FTMS analysis for lipid quantification, and FTMS(2) analysis using both HCD and CID and ITMS(3) analysis utilizing dual CID for in-depth structural characterization of molecular glycerophospholipid species. The performance of the MS(ALL) method was benchmarked in a comparative analysis of mouse cerebellum and hippocampus. This analysis demonstrated extensive lipidome quantification covering 311 lipid species encompassing 20 lipid classes, and identification of 202 distinct molecular glycerophospholipid species when applying a novel high confidence filtering strategy. The work presented here validates the performance of the Orbitrap Fusion mass spectrometer for in-depth lipidome analysis.

  1. High-resolving mass spectrographs and spectrometers

    NASA Astrophysics Data System (ADS)

    Wollnik, Hermann

    2015-11-01

    Discussed are different types of high resolving mass spectrographs and spectrometers. In detail outlined are (1) magnetic and electric sector field mass spectrographs, which are the oldest systems, (2) Penning Trap mass spectrographs and spectrometers, which have achieved very high mass-resolving powers, but are technically demanding (3) time-of-flight mass spectrographs using high energy ions passing through accelerator rings, which have also achieved very high mass-resolving powers and are equally technically demanding, (4) linear time-of-flight mass spectrographs, which have become the most versatile mass analyzers for low energy ions, while the even higher performing multi-pass systems have only started to be used, (5) orbitraps, which also have achieved remarkably high mass-resolving powers for low energy ions.

  2. Activated Ion ETD Performed in a Modified Collision Cell on a Hybrid QLT-Oribtrap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Ledvina, Aaron R.; Rose, Christopher M.; McAlister, Graeme C.; Syka, John E. P.; Westphall, Michael S.; Griep-Raming, Jens; Schwartz, Jae C.; Coon, Joshua J.

    2013-11-01

    We describe the implementation and characterization of activated ion electron transfer dissociation (AI-ETD) on a hybrid QLT-Orbitrap mass spectrometer. AI-ETD was performed using a collision cell that was modified to enable ETD reactions, in addition to normal collisional activation. The instrument manifold was modified to enable irradiation of ions along the axis of this modified cell with IR photons from a CO2 laser. Laser power settings were optimized for both charge (z) and mass to charge ( m/z) and the instrument control firmware was updated to allow for automated adjustments to the level of irradiation. This implementation of AI-ETD yielded 1.6-fold more unique identifications than ETD in an nLC-MS/MS analysis of tryptic yeast peptides. Furthermore, we investigated the application of AI-ETD on large scale analysis of phosphopeptides, where laser power aids ETD, but can produce b- and y-type ions because of the phosphoryl moiety's high IR adsorption. nLC-MS/MS analysis of phosphopeptides derived from human embryonic stem cells using AI-ETD yielded 2.4-fold more unique identifications than ETD alone, demonstrating a promising advance in ETD sequencing of PTM containing peptides.

  3. Activated ion ETD performed in a modified collision cell on a hybrid QLT-Oribtrap mass spectrometer.

    PubMed

    Ledvina, Aaron R; Rose, Christopher M; McAlister, Graeme C; Syka, John E P; Westphall, Michael S; Griep-Raming, Jens; Schwartz, Jae C; Coon, Joshua J

    2013-11-01

    We describe the implementation and characterization of activated ion electron transfer dissociation (AI-ETD) on a hybrid QLT-Orbitrap mass spectrometer. AI-ETD was performed using a collision cell that was modified to enable ETD reactions, in addition to normal collisional activation. The instrument manifold was modified to enable irradiation of ions along the axis of this modified cell with IR photons from a CO2 laser. Laser power settings were optimized for both charge (z) and mass to charge (m/z) and the instrument control firmware was updated to allow for automated adjustments to the level of irradiation. This implementation of AI-ETD yielded 1.6-fold more unique identifications than ETD in an nLC-MS/MS analysis of tryptic yeast peptides. Furthermore, we investigated the application of AI-ETD on large scale analysis of phosphopeptides, where laser power aids ETD, but can produce b- and y-type ions because of the phosphoryl moiety's high IR adsorption. nLC-MS/MS analysis of phosphopeptides derived from human embryonic stem cells using AI-ETD yielded 2.4-fold more unique identifications than ETD alone, demonstrating a promising advance in ETD sequencing of PTM containing peptides.

  4. Activated Ion ETD Performed in a Modified Collision Cell on a Hybrid QLT-Oribtrap Mass Spectrometer

    PubMed Central

    Ledvina, Aaron R.; Rose, Christopher M.; McAlister, Graeme C.; Syka, John E.P.; Westphall, Michael S.; Griep-Raming, Jens; Schwartz, Jae C.; Coon, Joshua J.

    2013-01-01

    We describe the implementation and characterization of activated ion electron transfer dissociation (AI-ETD) on a hybrid QLT-Orbitrap mass spectrometer. AI-ETD was performed using a collision cell that was modified to enable ETD reactions, in addition to normal collisional activation. The instrument manifold was modified to enable irradiation of ions along the axis of this modified cell with IR photons from a CO2 laser. Laser power settings were optimized for both charge (z) and mass to charge (m/z) and the instrument control firmware was updated to allow for automated adjustments to the level of irradiation. This implementation of AI-ETD yielded 1.6 fold more unique identifications than ETD in an nLC-MS/MS analysis of tryptic yeast peptides. Furthermore, we investigated the application of AI-ETD on large scale analysis of phosphopeptides, where laser power aids ETD, but can produce b- and y-type ions due to the phosphoryl moiety's high IR adsorption. nLC-MS/MS analysis of phosphopeptides derived from human embryonic stem cells using AI-ETD yielded 2.4 fold more unique identifications than ETD alone, demonstrating a promising advance in ETD sequencing of PTM containing peptides. PMID:23677544

  5. Observations of plasma dynamics in the coma of P/Halley by the Giotto ion mass spectrometer

    NASA Technical Reports Server (NTRS)

    Goldstein, B. E.; Goldstein, R.; Neugebauer, M.; Fuselier, S. A.; Shelley, E. G.; Balsiger, H.; Kettmann, G.; Ip, W.-H.; Rosenbauer, H.; Schwenn, R.

    1992-01-01

    The paper reports observations of plasma dynamics in the coma of P/Halley by the Giotto ion mass spectrometer. Measurements of protons and alpha particles from the far upstream region to the near ionopause region and of ions of mass 12-32 at distances of about 250,000 to 40,000 km from the nucleus are presented. The discontinuity known as the magnetic pileup boundary (MPB) is apparent only in proton, alpha particle, and magnetometer data, indicating that it is a tangential discontinuity of solar wind origin. No significant change is found in the properties of the heavy ions across the MPB. The issue of whether a cometopause was unambiguously observed at Comet Halley is discussed; it is concluded that the observations do not convincingly support the idea of a boundary due to internal cometary processes. A comparison of the observations to MHD models is made. The plasma flow directions at all distances greater than 30,000 km from the nucleus are in agreement with MHD calculations.

  6. The use of the ion probe mass spectrometer in the measurement of hydrogen concentration gradients in Monel K 500

    NASA Technical Reports Server (NTRS)

    Truhan, J. J., Jr.; Hehemann, R. F.

    1974-01-01

    The ion probe mass spectrometer was used to measure hydrogen concentration gradients in cathodically charged Monel K 500. Initial work with the ion probe involved the calibration of the instrument and the establishment of a suitable experimental procedure for this application. Samples of Monel K 500 were cathodically charged in a weak sulfuric acid solution. By varying the current density, different levels of hydrogen were introduced into the samples. Hydrogen concentration gradients were taken by ion sputtering on the surface of these samples and monitoring the behavior of the hydrogen mass peak as a function of time. An attempt was made to determine the relative amounts of hydrogen in the bulk and grain boundaries by analyzing a fresh fracture surface with a higher proportion of grain boundary area. It was found that substantially more hydrogen was detected in the grain boundaries than in the bulk, confirming the predictions of previous workers. A sputter rate determination was made in order to establish the rate of erosion.

  7. Maximizing Ion Transmission from Atmospheric Pressure into the Vacuum of Mass Spectrometers with a Novel Electrospray Interface

    NASA Astrophysics Data System (ADS)

    Krutchinsky, Andrew N.; Padovan, Júlio C.; Cohen, Herbert; Chait, Brian T.

    2015-04-01

    We have discovered that an electrode containing a conical channel with a small angular divergence can transmit into the vacuum almost 100% of an electrospray ion current produced at atmospheric pressure. Our first implementation of such a conical duct, which we term "ConDuct," uses a conductive plastic pipette tip containing an approximately 1.6° divergent channel at its entrance. We observed that the beam formed by the ConDuct electrode has a very low divergence (less than 1°) and persists for long distances in vacuum. Intrigued by these properties, we incorporated this electrode into a novel atmosphere-to-vacuum ion transmission interface, and devised a technique for evaluating its performance relative to the commercial reference interfaces that contain heated metal capillaries. We determined that our new interface transmits at least 400 times more ions than the commercial Thermo LCQ DECA XP atmosphere-to-vacuum interface and 2 to 3 times more than the commercial interface in the Thermo Velos Orbitrap and the Q Exactive mass spectrometers. We conclude that it might be possible to optimize the properties of the transmitted ions further by manufacturing ConDuct inlet electrodes from metal rather than conductive plastic and by determining the optimum angle of channel divergence and channel length.

  8. Maximizing ion transmission from atmospheric pressure into the vacuum of mass spectrometers with a novel electrospray interface.

    PubMed

    Krutchinsky, Andrew N; Padovan, Júlio C; Cohen, Herbert; Chait, Brian T

    2015-04-01

    We have discovered that an electrode containing a conical channel with a small angular divergence can transmit into the vacuum almost 100% of an electrospray ion current produced at atmospheric pressure. Our first implementation of such a conical duct, which we term "ConDuct," uses a conductive plastic pipette tip containing an approximately 1.6° divergent channel at its entrance. We observed that the beam formed by the ConDuct electrode has a very low divergence (less than 1°) and persists for long distances in vacuum. Intrigued by these properties, we incorporated this electrode into a novel atmosphere-to-vacuum ion transmission interface, and devised a technique for evaluating its performance relative to the commercial reference interfaces that contain heated metal capillaries. We determined that our new interface transmits at least 400 times more ions than the commercial Thermo LCQ DECA XP atmosphere-to-vacuum interface and 2 to 3 times more than the commercial interface in the Thermo Velos Orbitrap and the Q Exactive mass spectrometers. We conclude that it might be possible to optimize the properties of the transmitted ions further by manufacturing ConDuct inlet electrodes from metal rather than conductive plastic and by determining the optimum angle of channel divergence and channel length.

  9. Electron transfer dissociation in the hexapole collision cell of a hybrid quadrupole-hexapole Fourier transform ion cyclotron resonance mass spectrometer.

    PubMed

    Kaplan, Desmond A; Hartmer, Ralf; Speir, J Paul; Stoermer, Carsten; Gumerov, Dmitry; Easterling, Michael L; Brekenfeld, Andreas; Kim, Taeman; Laukien, Frank; Park, Melvin A

    2008-01-01

    Electron transfer dissociation (ETD) of proteins is demonstrated in a hybrid quadrupole-hexapole Fourier transform ion cyclotron resonance mass spectrometer (Qh-FTICRMS). Analyte ions are selected in the mass analyzing quadrupole, accumulated in the hexapole linear ion trap, reacted with fluoranthene reagent anions, and then analyzed via an FTICR mass analyzer. The hexapole trap allows for a broad fragment ion mass range and a high ion storage capacity. Using a 3 T FTICRMS, resolutions of 60 000 were achieved with mass accuracies averaging below 1.4 ppm. The high resolution, high mass accuracy ETD spectra provided by FTICR obviates the need for proton transfer reaction (PTR) charge state reduction of ETD product ions when analyzing proteins or large peptides. This is demonstrated with the ETD of ubiquitin and apomyoglobin yielding sequence coverages of 37 and 20%, respectively. We believe this represents the first reported successful combination of ETD and a FTICRMS.

  10. New High Resolution Ion Mobility Mass Spectrometer Capable of Measurements of Collision Cross Sections from 150 to 520 K.

    PubMed

    Ujma, Jakub; Giles, Kevin; Morris, Michael; Barran, Perdita E

    2016-10-04

    We present a new variable temperature (VT), high resolution ion mobility (IM) drift tube coupled to a commercial mass spectrometer (MS). Ions are generated in an electrospray ion source with a sampling cone interface and two stacked ring RF guides which transfer ions into the mobility analyzer located prior to a quadrupole time-of-flight mass spectrometer. The drift cell can be operated over a pressure range of 0.5-3 Torr and a temperature range of 150-520 K with applied fields typically between 3 and 14 V cm(-1). This makes the instrument suitable for rotationally averaged collision cross section (CCS) measurements at low E/N ratios where ions are near thermal equilibrium with the buffer gas. Fundamental studies of the effective ion temperatures can be performed at high E/N ratios. An RF ion trap/buncher is located at the beginning of the drift region, which modulates the continuous ion beam into spatially narrow packets. Packets of ions then drift in a linear electric field, which is 50.5 cm long, and are separated according to their mobility in an inert buffer gas. Post-drift, an ion funnel focuses the radially spread pulses of ions into the inlet of a commercial MS platform (Micromass QToF2). We present the novel features of this instrument and results from VT-IM-MS experiments on a range of model systems-IMS CCS standards (Agilent ESI Tune Mix), the monomeric protein Ubiquitin (8.6 kDa), and the tetrameric protein complex Concanavalin A (103 kDa). We evaluate the performance of the instrument by comparing ambient (DT)CCSHe values of model compounds with those found in the literature. Several effects of temperature on collision cross sections and resolution are observed. For small rigid molecules, changes in resolution are consistent with anticipated thermal diffusion effects. Changes in measured (DT)CCSHe for these rigid systems at different temperatures are attributed primarily to the effect of temperature on the long-range attractive interaction. Similar

  11. A thermosphere composition measurement using a quadrupole mass spectrometer with a side energy focussing quasi-open ion source

    NASA Technical Reports Server (NTRS)

    Niemann, H. B.; Spencer, N. W.; Schmitt, G. A.

    1971-01-01

    The atomic oxygen concentration in the altitude range 130 to 240 km was determined through the use of a quadrupole spectrometer with a strongly focussing ion source. The instrument is used in the Thermosphere Probe in a manner that greatly increases the proportion of measured oxygen ions that have not experienced a surface collision and permits quantitative evaluation of surface recombination and thermalization effects which inevitably enter all spectrometer determinations. The data obtained strengthen the concept that consideration of surface effects is significant in quantifying spectrometer measurements of reactive gases, and tend to be in agreement with von Zahn's recent results.

  12. Organic chemistry in Titan's upper atmosphere and its astrobiological consequences: I. Views towards Cassini plasma spectrometer (CAPS) and ion neutral mass spectrometer (INMS) experiments in space

    NASA Astrophysics Data System (ADS)

    Ali, A.; Sittler, E. C.; Chornay, D.; Rowe, B. R.; Puzzarini, C.

    2015-05-01

    The discovery of carbocations and carbanions by Ion Neutral Mass Spectrometer (INMS) and the Cassini Plasma Spectrometer (CAPS) instruments onboard the Cassini spacecraft in Titan's upper atmosphere is truly amazing for astrochemists and astrobiologists. In this paper we identify the reaction mechanisms for the growth of the complex macromolecules observed by the CAPS Ion Beam Spectrometer (IBS) and Electron Spectrometer (ELS). This identification is based on a recently published paper (Ali et al., 2013. Planet. Space Sci. 87, 96) which emphasizes the role of Olah's nonclassical carbonium ion chemistry in the synthesis of the organic molecules observed in Titan's thermosphere and ionosphere by INMS. The main conclusion of that work was the demonstration of the presence of the cyclopropenyl cation - the simplest Huckel's aromatic molecule - and its cyclic methyl derivatives in Titan's atmosphere at high altitudes. In this study, we present the transition from simple aromatic molecules to the complex ortho-bridged bi- and tri-cyclic hydrocarbons, e.g., CH2+ mono-substituted naphthalene and phenanthrene, as well as the ortho- and peri-bridged tri-cyclic aromatic ring, e.g., perinaphthenyl cation. These rings could further grow into tetra-cyclic and the higher order ring polymers in Titan's upper atmosphere. Contrary to the pre-Cassini observations, the nitrogen chemistry of Titan's upper atmosphere is found to be extremely rich. A variety of N-containing hydrocarbons including the N-heterocycles where a CH group in the polycyclic rings mentioned above is replaced by an N atom, e.g., CH2+ substituted derivative of quinoline (benzopyridine), are found to be dominant in Titan's upper atmosphere. The mechanisms for the formation of complex molecular anions are discussed as well. It is proposed that many closed-shell complex carbocations after their formation first, in Titan's upper atmosphere, undergo the kinetics of electron recombination to form open-shell neutral

  13. Lunar orbital mass spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Lord, W. P.

    1971-01-01

    The design, development, manufacture, test and calibration of five lunar orbital mass spectrometers with the four associated ground support equipment test sets are discussed. A mass spectrometer was installed in the Apollo 15 and one in the Apollo 16 Scientific Instrument Module within the Service Module. The Apollo 15 mass spectrometer was operated with collection of 38 hours of mass spectra data during lunar orbit and 50 hours of data were collected during transearth coast. The Apollo 16 mass spectrometer was operated with collection of 76 hours of mass spectra data during lunar orbit. However, the Apollo 16 mass spectrometer was ejected into lunar orbit upon malfunction of spacecraft boom system just prior to transearth insection and no transearth coast data was possible.

  14. Characterization of TATP gas phase product ion chemistry via isotope labeling experiments using ion mobility spectrometry interfaced with a triple quadrupole mass spectrometer.

    PubMed

    Tomlinson-Phillips, Jill; Wooten, Alfred; Kozole, Joseph; Deline, James; Beresford, Pamela; Stairs, Jason

    2014-09-01

    Identification of the fragment ion species associated with the ion reaction mechanism of triacetone triperoxide (TATP), a homemade peroxide-based explosive, is presented. Ion mobility spectrometry (IMS) has proven to be a key analytical technique in the detection of trace explosive material. Unfortunately, IMS alone does not provide chemical identification of the ions detected; therefore, it is unknown what ion species are actually formed and separated by the IMS. In IMS, ions are primarily characterized by their drift time, which is dependent on the ion׳s mass and molecular cross-section; thus, IMS as a standalone technique does not provide structural signatures, which is in sharp contrast to the chemical and molecular information that is generally obtained from other customary analytical techniques, such as NMR, Raman and IR spectroscopy and mass spectrometry. To help study the ion chemistry that gives rise to the peaks observed in IMS, the hardware of two different commercial IMS instruments has been directly coupled to triple quadrupole (QQQ) mass spectrometers, in order to ascertain each ion׳s corresponding mass/charge (m/z) ratios with different dopants at two temperatures. Isotope labeling was then used to help identify and confirm the molecular identity of the explosive fragment and adduct ions of TATP. The m/z values and isotope labeling experiments were used to help propose probable molecular formulas for the ion fragments. In this report, the fragment and adduct ions m/z 58 and 240 of TATP have been confirmed to be [C3H6NH·H](+) and [TATP·NH4](+), respectively; while the fragment ions m/z 73 and 89 of TATP are identified as having the molecular formulas [C4H9NH2](+) and [C4H9O2](+), respectively. It is anticipated that the work in this area will not only help to facilitate improvements in mobility-based detection (IMS and MS), but also aid in the development and optimization of MS-based detection algorithms for TATP.

  15. Unambiguous characterization of analytical markers in complex, seized opiate samples using an enhanced ion mobility trace detector-mass spectrometer.

    PubMed

    Liuni, Peter; Romanov, Vladimir; Binette, Marie-Josée; Zaknoun, Hafid; Tam, Maggie; Pilon, Pierre; Hendrikse, Jan; Wilson, Derek J

    2014-11-04

    Ion mobility spectroscopy (IMS)-based trace-compound detectors (TCDs) are powerful and widely implemented tools for the detection of illicit substances. They combine high sensitivity, reproducibility, rapid analysis time, and resistance to dirt with an acceptable false alarm rate. The analytical specificity of TCD-IMS instruments for a given analyte depends strongly on a detailed knowledge of the ion chemistry involved, as well as the ability to translate this knowledge into field-robust analytical methods. In this work, we introduce an enhanced hybrid TCD-IMS/mass spectrometer (TCD-IMS/MS) that combines the strengths of ion-mobility-based target compound detection with unambiguous identification by tandem MS. Building on earlier efforts along these lines (Kozole et al., Anal. Chem. 2011, 83, 8596-8603), the current instrument is capable of positive and negative-mode analyses with tightly controlled gating between the IMS and MS modules and direct measurement of ion mobility profiles. We demonstrate the unique capabilities of this instrument using four samples of opium seized by the Canada Border Services Agency (CBSA), consisting of a mixture of opioid alkaloids and other naturally occurring compounds typically found in these samples. Although many analytical methods have been developed for analyzing naturally occurring opiates, this is the first detailed ion mobility study on seized opium samples. This work demonstrates all available analytical modes for the new IMS-MS system including "single-gate", "dual-gate", MS/MS, and precursor ion scan methods. Using a combination of these modes, we unambiguously identify all signals in the IMS spectra, including previously uncharacterized minor peaks arising from compounds that are common in raw opium.

  16. In situ SIMS analysis and reactions of surfaces prepared by soft landing of mass-selected cations and anions using an ion trap mass spectrometer.

    PubMed

    Nie, Zongxiu; Li, Guangtao; Goodwin, Michael P; Gao, Liang; Cyriac, Jobin; Cooks, R Graham

    2009-06-01

    Mass-selected polyatomic cations and anions, produced by electrosonic spray ionization (ESSI), were deposited onto polycrystalline Au or fluorinated self-assembled monolayer (FSAM) surfaces by soft landing (SL), using a rectilinear ion trap (RIT) mass spectrometer. Protonated and deprotonated molecules, as well as intact cations and anions generated from such molecules as peptides, inorganic catalysts, and fluorescent dyes, were soft-landed onto the surfaces. Analysis of the modified surfaces was performed in situ by Cs(+) secondary ion mass spectrometry (SIMS) using the same RIT mass analyzer to characterize the sputtered ions as that used to mass select the primary ions for SL. Soft-landing times as short as 30 s provided surfaces that yielded good quality SIMS spectra. Chemical reactions of the surfaces modified by SL were generated in an attached reaction chamber into which the surface was transferred under vacuum. For example, a surface on which protonated triethanolamine had been soft landed was silylated using vapor-phase chlorotrimethylsilane before being returned still under vacuum to the preparation chamber where SIMS analysis revealed the silyloxy functionalization. SL and vapor-phase reactions are complementary methods of surface modification and in situ surface analysis by SIMS is a simple way to characterize the products produced by either technique.

  17. Negative ion electrospray of bromo- and chloroacetic acids and an evaluation of exact mass measurements with a bench-top time-of-flight mass spectrometer

    PubMed

    Debre; Budde; Song

    2000-09-01

    The negative ion electrospray mass spectra of six bromo- and chloroacetic acids were measured using two different electrospray interfaces and single quadrupole and bench-top time-of-flight mass spectrometers. With each acid at 50 microg/mL in aqueous methanol at pH 10, the anions observed included deprotonated molecules, adducts, and fragment ions. With each acid at 100 ng/mL in aqueous acetonitrile at pH 10, mainly deprotonated molecules are observed. The exact m/z measuring capability of the time-of-flight mass spectrometer was evaluated to assess the potential for the determination of the individual acids in mixtures without an on-line separation. Mean measurement errors were nearly always less than +/- 9 ppm and the majority were less than +/- 5 ppm. Potential interferences by substances having similar exact masses and the ability to form anions in aqueous solutions were evaluated. The estimated detection limits of the five regulated haloacetic acids in drinking water, without a sample preconcentration step, are in the range of 24-86 ng/mL, which is within about a factor of 10 of the levels required for routine monitoring of the acids. Actual drinking water samples were not analyzed pending the development of slightly more sensitive techniques and quantitative analytical procedures.

  18. Surface-induced dissociation of ion mobility-separated noncovalent complexes in a quadrupole/time-of-flight mass spectrometer.

    PubMed

    Zhou, Mowei; Huang, Chengsi; Wysocki, Vicki H

    2012-07-17

    A custom in-line surface-induced dissociation (SID) device has been incorporated into a commercial ion mobility quadrupole/time-of-flight mass spectrometer in order to provide an alternative and potentially more informative activation method than the commonly used collision-induced dissociation (CID). Complicated sample mixtures can be fractionated by ion mobility (IM) and then dissociated by CID or SID for further structural analysis. Interpretation of SID spectra for cesium iodide clusters was greatly simplified with IM prior to dissociation because products originating from different precursors and overlapping in m/z but separated in drift time can be examined individually. Multiple conformations of two protein complexes, source-activated transthyretin tetramer and nativelike serum amyloid P decamer, were separated in ion mobility and subjected to CID and SID. CID spectra of the mobility separated conformations are similar. However, drastic differences can be observed for SID spectra of different conformations, implying different structures in the gas phase. This work highlights the potential of utilizing IM-SID to study quaternary structures of protein complexes and provides information that is complementary to our recently reported SID-IM approach.

  19. Action spectroscopy of SrCl{sup +} using an integrated ion trap time-of-flight mass spectrometer

    SciTech Connect

    Puri, Prateek Schowalter, Steven J.; Hudson, Eric R.; Kotochigova, Svetlana; Petrov, Alexander

    2014-07-07

    The photodissociation cross-section of SrCl{sup +} is measured in the spectral range of 36 000–46 000 cm{sup −1} using a modular time-of-flight mass spectrometer (TOF-MS). By irradiating a sample of trapped SrCl{sup +} molecular ions with a pulsed dye laser, X{sup 1}Σ{sup +} state molecular ions are electronically excited to the repulsive wall of the A{sup 1}Π state, resulting in dissociation. Using the TOF-MS, the product fragments are detected and the photodissociation cross-section is determined for a broad range of photon energies. Detailed ab initio calculations of the SrCl{sup +} molecular potentials and spectroscopic constants are also performed and are found to be in good agreement with experiment. The spectroscopic constants for SrCl{sup +} are also compared to those of another alkaline earth halogen, BaCl{sup +}, in order to highlight structural differences between the two molecular ions. This work represents the first spectroscopy and ab initio calculations of SrCl{sup +}.

  20. On-Line Desalting of Crude Oil in the Source Region of a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Chanthamontri, C. Ken; Stopford, Andrew P.; Snowdon, Ryan W.; Oldenburg, Thomas B. P.; Larter, Stephen R.

    2014-08-01

    The presence of dissolved metal ions in waters associated with crude oils has many negative implications for the transport, processing, and refining of petroleum. In addition, mass spectrometric analysis of sodium containing crude oil samples suffers from ionization suppression, unwanted adduct formation, and an increase in the complexity of data analysis. Here, we describe a method for the reduction/elimination of these adverse effects by modification of the source region gas-inlet system of a 12 T Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Several acids were examined as part of this study, with the most suitable for on-line desalting found to have both high vapor pressure and low pKa; 12.1 M HCl showed the strongest desalting effect for crude oil samples with a sodium removal index (SRI) of 88%-100% ± 7% for the NaOS compound class. In comparison, a SRI of only 38% ± 9% was observed for a H2O/toluene solution-phase extraction of Oil 1. These results clearly demonstrate the increased efficacy of pseudo-vapor phase desalting with the additional advantages that initial sample solution conditions are preserved and no sample preparation is required prior to analysis.

  1. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer.

    PubMed

    Zacek, Petr; Bukowski, Michael; Rosenberger, Thad A; Picklo, Matthew

    2016-12-01

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PCs. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PCs. This approach is comprised of two MS methods: a precursor ion scanning (PIS) of mass m/z 184 in positive mode (PIS m/z +184) and MS(3) fragmentation in negative mode, both performed on the same instrument, a hybrid triple quadrupole ion-trap mass spectrometer. The MS(3) experiment identified the FA composition and the relative abundance of isobaric and sn-1, sn-2 positional isomeric PC species, which were subsequently combined with absolute quantitative data obtained by PIS m/z +184 scan. This approach was applied to the analysis of a National Institute of Standards and Technology human blood plasma standard reference material (SRM 1950). We quantified more than 70 PCs and confirmed that a majority are present in isobaric and isomeric mixtures. The FA content determined by this method was comparable to that obtained using GC with flame ionization detection, supporting the quantitative nature of this MS method. This methodology will provide more in-depth biomarker information for clinical and mechanistic studies.

  2. High-Capacity Ion Trap Coupled to a Time-of-Flight Mass Spectrometer for Comprehensive Linked Scans with no Scanning Losses

    PubMed Central

    Myung, Sunnie; Cohen, Herbert; Fenyo, David; Padovan, Julio C.; Krutchinsky, Andrew N.

    2010-01-01

    A high-capacity ion trap coupled to a time-of-flight (TOF) mass spectrometer has been developed to carry out comprehensive linked scan analysis of all stored ions in the ion trap. The approach involves a novel tapered geometry high-capacity ion trap that can store more than 106 ions (range 800-4000 m/z) without degrading its performance. Ions are stored and scanned out from the high-capacity ion trap as a function of m/z, collisionally fragmented and analyzed by TOF. Accurate mass analysis is achieved on both the precursor and fragment ions of all species ejected from the ion trap. We demonstrate the approach for comprehensive linked-scan identification of phosphopeptides in mixtures with their corresponding unphosphorylated peptides. PMID:21516228

  3. CID of singly charged antioxidants applied in lubricants by means of a 3D ion trap and a linear ion trap-Orbitrap mass spectrometer.

    PubMed

    Kassler, Alexander; Pittenauer, Ernst; Doerr, Nicole; Allmaier, Guenter

    2011-06-01

    The aim of this study was to investigate the fragmentation behavior induced by low-energy collision-induced dissociation (LE-CID) of four selected antioxidants applied in lubricants, by two different types of ion trap mass spectrometers: a three-dimensional ion trap (3D-IT) and a linear IT (LIT) Orbitrap MS. Two sterically hindered phenols and two aromatic amines were selected as model compounds representing different antioxidant classes and were characterized by positive-ion electrospray ionization (ESI) and LE-CID. Various types of molecular ions (e.g. [M](+•) , [M + H](+) , [M + NH(4) ](+) or [M + Na](+) ) were used as precursor ions generating a significant number of structurally relevant product ions. Furthermore, the phenolic compounds were analyzed by negative-ion ESI. For both IT types applied for fragmentation, the antioxidants exhibited the same unusual LE-CID behavior: (1) they formed stable radical product ions and (2) CC bond cleavages of aliphatic substituents were observed and their respective cleavage sites depended on the precursor ion selected. This fragmentation provided information on the type of structural isomer usually not obtainable for branched aliphatic substituents utilizing LE-CID. Comparing the two instruments, the main benefit of applying the LIT-Orbitrap was direct access to elemental composition of product ions enabling unambiguous interpretation of fragmentation trees not obtainable by the 3D-IT device (e.g. loss of isobaric neutrals). It should be emphasized that the types of product ions formed do not depend on the type of IT analyzer applied. For characterizing degradation products of antioxidants, the LIT-Orbitrap hybrid system, allowing the determination of accurate m/z values for product ions, is the method of choice.

  4. High-Resolution Mass Spectrometers

    NASA Astrophysics Data System (ADS)

    Marshall, Alan G.; Hendrickson, Christopher L.

    2008-07-01

    Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

  5. Commercial intermediate pressure MALDI ion mobility spectrometry mass spectrometer capable of producing highly charged laserspray ionization ions.

    PubMed

    Inutan, Ellen D; Wang, Beixi; Trimpin, Sarah

    2011-02-01

    The first examples of highly charged ions observed under intermediate pressure (IP) vacuum conditions are reported using laser ablation of matrix/analyte mixtures. The method and results are similar to those obtained at atmospheric pressure (AP) using laserspray ionization (LSI) and/or matrix assisted inlet ionization (MAII). Electrospray ionization (ESI), LSI, and MAII are methods operating at AP and have been shown, with or without the use of a voltage or a laser, to produce highly charged ions with very similar ion abundance and charge states. A commercial matrix-assisted laser desorption/ionization ion mobility spectrometry (IMS) mass spectrometry (MS) instrument (SYNAPT G2) was used for the IP developments. The necessary conditions for producing highly charged ions of peptides and small proteins at IP appear to be a pressure drop region and the use of suitable matrixes and laser fluence. Ionization to produce these highly charged ions under the low pressure conditions of IP does not require specific heating or a special inlet ion transfer region. However, under the current setup, ubiquitin is the highest molecular weight protein observed. These findings are in accord with the need to provide thermal energy in the pressure drop region, similar to LSI and MAII, to improve sensitivity and extend the types of compounds that produce highly charged ions. The practical utility of IP-LSI in combination with IMS-MS is demonstrated for the analysis of model mixtures composed of a lipid, peptides, and a protein. Further, endogenous multiply charged peptides are observed directly from delipified mouse brain tissue with drift time distributions that are nearly identical in appearance to those obtained from a synthesized neuropeptide standard analyzed by either LSI- or ESI-IMS-MS at AP. Efficient solvent-free gas-phase separation enabled by the IMS dimension separates the multiply charged peptides from lipids that remained on the delipified tissue. Lipid and peptide

  6. Evaluation of Small Mass Spectrometer Systems

    NASA Technical Reports Server (NTRS)

    Arkin, C. Richard; Griffin, Timothy P.; Ottens, Andrew K.; Diaz, Jorge A.; Follistein, Duke W.; Adams, Fredrick W.; Helms, William R.; Voska, N. (Technical Monitor)

    2002-01-01

    Various mass analyzer systems were evaluated. Several systems show promise, including the Stanford Research Systems RGA-100, Inficon XPR-2, the University of Florida's Ion Trap, and the Compact Double Focus Mass Spectrometer. Areas that need improvement are the response time, recovery time, system volume, and system weight. Future work will investigate techniques to improve systems and will evaluate engineering challenges.

  7. Quantitative comparison of a flared and a standard heated metal capillary inlet with a voltage-assisted air amplifier on an electrospray ionization linear ion trap mass spectrometer.

    PubMed

    Dixon, R Brent; Muddiman, David C

    2007-01-01

    The performance characteristics (i.e., ion abundance and electrospray ion current) of a flared and blunt-ended heated metal capillary were evaluated with a voltage-assisted air amplifier on a linear ion trap mass spectrometer (LTQ-MS). The results demonstrated that a standard capillary afforded higher ion abundance than a flared capillary, thus further work is necessary to investigate conditions for which significant benefits with the flared capillary will be observed. The compatibility of a voltage-assisted air amplifier is explored for both types of capillaries and in all cases resulted in improved ion abundance and spray current.

  8. A 3T external source quadrupole Fourier transform mass spectrometer for ion/molecule reactions and analysis

    NASA Astrophysics Data System (ADS)

    McCullough, Sési M.; Gard, Eric; Lebrilla, Carlito B.

    1991-06-01

    A versatile quadrupole Fourier transform mass spectrometry instrument for both ion/molecule chemistry and analysis is described. Preliminary results show that despite the relatively low field (3T), a large mass range (up to m/z 16 000) and high resolution (41 000 FWHH at m/z 1692) are obtained. Metal ions (e.g. Fe+) for ion/molecule chemistry and organic ions (e.g. maltose) for analysis are routinely produced via secondary ion mass spectrometry (and liquid secondary ion mass spectrometry) in the external source.

  9. A miniaturised electron ionisation time-of-flight mass spectrometer that uses a unique helium ion removal pulsing technique specifically for gas analysis.

    PubMed

    Qing, Jiang; Huang, Zhengxu; Zhang, Yan; Zhu, Hui; Tan, Guobin; Gao, Wei; Yang, Peng-yuan

    2013-06-21

    A miniaturised reflectron time-of-flight mass spectrometer combined with an electron ionisation ion source has been developed for the analysis of gases. An entirely new helium ion removal pulsing technique in this mass spectrometer is used to achieve an improved performance for the first time. The helium carrier gas, which enters into the source along with the gaseous sample, is simultaneously ionised and then orthogonally introduced into the time-of-fight mass analyser. Once the relatively light helium ions in the ion packet become extremely close to the reflectron plate (B-plate for short in this article), a modulated pulse is instantaneously applied on the B-plate and a negative reflectron voltage is set to the B-plate and lasts for a very short period, during which all the helium ions are directly bumped into the B-plate and subsequently removed. The helium ion removal pulsing technique can efficiently avoid saturation of the micro-channel plate caused by too many helium ions. A compact and durable instrument is designed, which has a mass resolving resolution greater than 400 FWHM for online gas analysis. The technology may also be further developed to remove other ions for TOF mass spectrometry.

  10. Modified ion source triple quadrupole mass spectrometer gas chromatograph for polycyclic aromatic hydrocarbon analyses

    PubMed Central

    Anderson, Kim A.; Szelewski, Michael J.; Wilson, Glenn; Quimby, Bruce D.; Hoffman, Peter D.

    2015-01-01

    We describe modified gas chromatography electron-impact/triple-quadrupole mass spectrometry (GC–EI/MS/MS) utilizing a newly developed hydrogen-injected self-cleaning ion source and modified 9 mm extractor lens. This instrument, with optimized parameters, achieves quantitative separation of 62 polycyclic aromatic hydrocarbons (PAHs). Existing methods historically limited rigorous identification and quantification to a small subset, such as the 16 PAHs the US EPA has defined as priority pollutants. Without the critical source and extractor lens modifications, the off-the-shelf GC–EI/MS/MS system was unsuitable for complex PAH analysis. Separations were enhanced by increased gas flow, a complex GC temperature profile incorporating multiple isothermal periods, specific ramp rates, and a PAH-optimized column. Typical determinations with our refined GC–EI/MS/MS have a large linear range of 1–10,000 pg μl−1 and detection limits of <2 pg μl−1. Included in the 62 PAHs, multiple-reaction-monitoring (MRM) mode enabled GC-EI/MS/MS identification and quantitation of several constituents of the MW 302 PAHs isomers. Using calibration standards, values determined were within 5% of true values over many months. Standard curve r2 values were typically >0.998, exceptional for compounds which are archetypally difficult. With this method benzo[a]fluorene, benzo[b]fluorene, benzo[c]fluorene were fully separated as was benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[j]fluoranthene. Chrysene and triphenylene, were sufficiently separated to allow accurate quantitation. Mean limits of detection (LODs) across all PAHs were 1.02 ± 0.84 pg μl−1 with indeno[1,2,3-c,d] pyrene having the lowest LOD at 0.26 pg μl−1 and only two analytes above 2.0 pg μl−1; acenaphthalene (2.33 pg μl−1) and dibenzo[a,e]pyrene (6.44 pg μl−1). PMID:26454790

  11. Instrumentation and methodology for simultaneous excitation/detection of ions in an FTICR mass spectrometer

    PubMed

    Schmidt; Fiorentino; Arkin; Laude

    2000-08-01

    A method for direct and continuous detection of ion motion during different perturbation events of the fourier transform ion cyclotron resonance (FTICR) experiment is demonstrated. The modifications necessary to convert an ordinary FTICR cell into one capable of performing simultaneous excitation/detection (SED) using a capacitive network are outlined. With these modifications, a 200-fold reduction in the detection of the coupled excitation signal is achieved. This allows the unique ability not only to observe the response to the perturbation but to observe the perturbation event itself. SED is used successfully to monitor the ion cyclotron transient during single-frequency excitation, remeasurement and exciter-excite experiments.

  12. Analysis of high mass-to-charge ions in a quadrupole ion trap mass spectrometer via an end-cap quadrupolar direct current downscan.

    PubMed

    Prentice, Boone M; McLuckey, Scott A

    2012-09-04

    A method for performing mass-selective instability analysis in a three-dimensional (3-D) quadrupole ion trap is described that involves scanning a direct current (dc) voltage applied to the end-cap electrodes while holding the radio frequency (rf) potential at a fixed value. Rather than eject at the ß(z) = 1 instability line by ramping the amplitude of the drive rf potential applied to the ring electrode, as with the original mass-selective instability scan, this approach effects ion ejection along the ß(z) = 0 instability line in a process identical in principle (though it varies in its method of implementation) to the previously termed "downscan" ( Todd , J. F. J. ; Penman , A. D. ; Smith , R. D. Int. J. Mass Spectrom. Ion Processes 1991 , 106 , 117 - 135 ). A linear scan of the dc amplitude results in a nonlinear mass scale, unlike the conventional resonance ejection scan with a linear scan of the rf amplitude, and the ejection of ions in the direction of high mass-to-charge (m/z) to low m/z. However, the downscan offers some advantages over the traditional rf scan for ions of high m/z values. These include a larger scannable mass range, as well as the opportunity for improved resolution at high mass. These characteristics are demonstrated with ions of m/z 10(4)-10(5).

  13. Detection of cw-related species in complex aerosol particles deposited on surfaces with an ion trap-based aerosol mass spectrometer

    SciTech Connect

    Harris, William A; Reilly, Pete; Whitten, William B

    2007-01-01

    A new type of aerosol mass spectrometer was developed by minimal modification of an existing commercial ion trap to analyze the semivolatile components of aerosols in real time. An aerodynamic lens-based inlet system created a well-collimated particle beam that impacted into the heated ionization volume of the commercial ion trap mass spectrometer. The semivolatile components of the aerosols were thermally vaporized and ionized by electron impact or chemical ionization in the source. The nascent ions were extracted and injected into the ion trap for mass analysis. The utility of this instrument was demonstrated by identifying semivolatile analytes in complex aerosols. This study is part of an ongoing effort to develop methods for identifying chemical species related to CW agent exposure. Our efforts focused on detection of CW-related species doped on omnipresent aerosols such as house dust particles vacuumed from various surfaces found in any office building. The doped aerosols were sampled directly into the inlet of our mass spectrometer from the vacuumed particle stream. The semivolatile analytes were deposited on house dust and identified by positive ion chemical ionization mass spectrometry up to 2.5 h after deposition. Our results suggest that the observed semivolatile species may have been chemisorbed on some of the particle surfaces in submonolayer concentrations and may remain hours after deposition. This research suggests that identification of trace CW agent-related species should be feasible by this technique.

  14. Rapid discrimination of bacteria using a miniature mass spectrometer.

    PubMed

    Pulliam, Christopher J; Wei, Pu; Snyder, Dalton T; Wang, Xiao; Ouyang, Zheng; Pielak, Rafal M; Graham Cooks, R

    2016-03-07

    Bacteria colonies were analyzed using paper spray ionization coupled with a portable mass spectrometer. The spectra were averaged and processed using multivariate analysis to discriminate between different species of bacteria based on their unique phospholipid profiles. Full scan mass spectra and product ion MS/MS data were compared to those recorded using a benchtop linear ion trap mass spectrometer.

  15. Threshold collision-induced dissociation measurements using a ring ion guide as the collision cell in a triple-quadrupole mass spectrometer.

    PubMed

    Romanov, Vladimir; Verkerk, Udo H; Siu, Chi-Kit; Hopkinson, Alan C; Siu, K W Michael

    2009-08-15

    A triple-quadrupole mass spectrometer has been modified for bond-dissociation energy measurements via threshold collision-induced dissociations (TCIDs) by replacing the conventional collision cell with a ring ion guide. Optimal operating conditions for the ring ion guide were determined or derived, and validated using a set of complexes for which bond dissociation energies are known. A comparison with reference data (within a range of 16-57 kcal/mol) indicates an accuracy approaching that of TCID determined on a guided ion-beam mass spectrometer. Complexes for which bond-dissociation energies were measured include metal ion complexes of simple ligands, amino acids and peptides, as well as of carbonic acid. There is excellent agreement between our experimental data and literature data, as well as theoretical data determined using a high-level computational method.

  16. Photon emissions from N2·+ ion beam-target gas collisions in a modified commercial sector mass spectrometer

    NASA Astrophysics Data System (ADS)

    Holmes, H. L.; Mayer, P. M.; Mommers, A. A.

    1994-08-01

    Experiments are reported in which radiative emissions from 8 keV N2·+ projectile ion--target gas (He, N2, O2 and CO2) collisions in the third field-free region of a modified VG ZAB-2F mass spectrometer (BEE geometry) were detected and analyzed using a scanning grating monochromator. The emission spectra between 180 and 680 nm were characterized by the N2·+ (B2[Sigma]u+ --> X2[Sigma]g+) electronic transition and, when N2 and O2 were the targets, the C 3[Pi]u --> B 3[Pi]g second positive system in N2. Fragment N+ emissions were also observed. In addition to the projectile emissions, ionized target gas and even target fragment emissions were present with all targets except helium. Observations made 0.05-0.17 [mu]s after the collision event were similar to those described above, but lacking target gas emissions. Qualitative information concerning the trends in post-collission emission, studied with 18 target gases, was obtained using wavelength cut-off filters. The results were consistent with the above spectral assignments and trends observed in collision induced dissociation mass spectrometry.

  17. A Tuning Method for Electrically Compensated Ion Cyclotron Resonance Mass Spectrometer Traps

    PubMed Central

    Brustkern, Adam M.; Rempel, Don L.; Gross, Michael L.

    2010-01-01

    We describe a method for tuning electrically compensated ion cyclotron resonance (ICR) traps by tracking the observed cyclotron frequency of an ion cloud at different oscillation mode amplitudes. Although we have used this method to tune the compensation voltages of a custom-built electrically compensated trap, the approach is applicable to other designs that incorporate electrical compensation. To evaluate the effectiveness of tuning, we examined the frequency shift as a function of cyclotron orbit size at different z-mode oscillation amplitudes. The cyclotron frequencies varied by ~ 12 ppm for ions with low z-mode oscillation amplitudes compared to those with high z-mode amplitudes. This frequency difference decreased to ~1 ppm by one iteration of trap tuning. PMID:20060743

  18. Construction and operation of parallel electric and magnetic field spectrometers for mass/energy resolved multi-ion charge exchange diagnostics on the Tokamak Fusion Test Reactor

    NASA Astrophysics Data System (ADS)

    Medley, S. S.; Roquemore, A. L.

    1998-07-01

    A novel charge exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory for neutral particle diagnostics on the Tokamak Fusion Test Reactor (TFTR). The E∥B spectrometer has an energy range of 0.5⩽A (amu)E (keV)⩽600 and provides mass-resolved energy spectra of H+, D+, and T+ (or 3He+) ion species simultaneously during a single discharge. The detector plane exhibits parallel rows of analyzed ions, each row containing the energy dispersed ions of a given mass-to-charge ratio. The detector consists of a large area microchannel plate (MCP) which is provided with three rectangular, semicontinuous active area strips, one coinciding with each of the mass rows for detection of H+, D+, and T+ (or 3He+) and each mass row has 75 energy channels. To suppress spurious signals attending operation of the plate in the magnetic fringe field of the spectrometer, the MCP was housed in a double-walled iron shield with a wire mesh ion entrance window. Using an accelerator neutron generator, the MCP neutron detection efficiency was measured to be 1.7×10-3 and 6.4×10-3 counts/neutron/cm2 for 2.5 MeV-DD and 14 MeV-DT neutrons, respectively. The design and calibration of the spectrometer are described in detail, including the effect of MCP exposure to tritium, and results obtained during high performance D-D operation on TFTR are presented to illustrate the performance of the E∥B spectrometer. The spectrometers were not used during D-T plasma operation due to the cost of providing the required radiation shielding.

  19. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1997-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  20. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1998-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  1. Method for increasing the dynamic range of mass spectrometers

    DOEpatents

    Belov, Mikhail; Smith, Richard D.; Udseth, Harold R.

    2004-09-07

    A method for enhancing the dynamic range of a mass spectrometer by first passing a sample of ions through the mass spectrometer having a quadrupole ion filter, whereupon the intensities of the mass spectrum of the sample are measured. From the mass spectrum, ions within this sample are then identified for subsequent ejection. As further sampling introduces more ions into the mass spectrometer, the appropriate rf voltages are applied to a quadrupole ion filter, thereby selectively ejecting the undesired ions previously identified. In this manner, the desired ions may be collected for longer periods of time in an ion trap, thus allowing better collection and subsequent analysis of the desired ions. The ion trap used for accumulation may be the same ion trap used for mass analysis, in which case the mass analysis is performed directly, or it may be an intermediate trap. In the case where collection is an intermediate trap, the desired ions are accumulated in the intermediate trap, and then transferred to a separate mass analyzer. The present invention finds particular utility where the mass analysis is performed in an ion trap mass spectrometer or a Fourier transform ion cyclotron resonance mass spectrometer.

  2. Data Reduction and Analysis of Pioneer Venus Orbital Ion Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Cloutier, Paul A.

    1996-01-01

    Research was carried out on developing a flow field interaction model for both the dayside and nightside ionosphere of Venus. Specific topics related to the dayside ionosphere included: (1) wave particle mechanisms at the ionopause, (2) structure and dynamics of the Venus ionopause and Ionosphere, and (3) flows and fields in the Venus Ionosphere. The structure and dynamics of ion troughs was also studied in the nightside ionosphere of Venus.

  3. A Quadrupole Ion Trap Mass Spectrometer for Quantitative Analysis of Nitrogen-Purged Compartments within the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Ottens, Andrew K.; Griffin, Timothy P.; Helms, William R.; Yost, Richard A.; Steinrock, T. (Technical Monitor)

    2001-01-01

    To enter orbit the Space Shuttle burns 1.8 million liters of liquid hydrogen combined with 0.8 million liters of liquid oxygen through three rocket engines mounted in the aft. NASA monitors the nitrogen-purged aft compartment for increased levels of hydrogen or oxygen in order to detect and determine the severity of a cryogenic fuel leak. Current monitoring is accomplished with a group of mass spectrometer systems located as much as 400 feet away from the shuttle. It can take up to 45 seconds for gas to reach the mass spectrometer, which precludes monitoring for leaks in the final moments before liftoff (the orbiter engines are started at T-00:06 seconds). To remedy the situation, NASA is developing a small rugged mass spectrometer to be used as point-sources around the Space Shuttle.

  4. The development of an Omegratron plasma ion mass spectrometer for Alcator C-Mod

    SciTech Connect

    Thomas, E.E. Jr.

    1993-05-01

    A new diagnostic device, the Omegatron Probe, has been developed to investigate relative impurity levels and impurity charge state distribution in the Alcator C-Mod Tokamak edge plasma. The Omegatron probe consists of two principal components, a ``front-end`` of independently biased grids, arranged in a gridded energy analyzer fashion and a large collection cavity. Particles enter the probe in a thin ``ribbon`` through a knife-edge slit. The grids provide a means to measure and control the parallel energy distribution of the ions. In the collection cavity, an oscillating electric field is applied perpendicularly to the ambient magnetic field. Ions whose cyclotron frequencies are resonant with this electric field oscillation will gain perpendicular energy and be collected. In this way, the probe can be operated in two modes: first, by fixing the potentials on the grids and sweeping frequencies to obtain a `` Z/m spectrum`` of ion species and second, by fixing the frequency and sweeping the grid potentials to obtain the distribution function of an individual impurity species. The Omegatron probe performed successfully in tests on a Hollow Cathode Discharge (HCD) linear plasma column. It obtained measurements of T{sub e} {approx} 5 eV, T{sub i} (H{sup +}) {approx} 2.0 {plus_minus} 0.2 eV, n{sub 0} {approx} 9 {times} 10{sup 15} m{sup {minus}3}, RMS potential fluctuation levels of {approximately} 0.5 {plus_minus} 0.05 {plus_minus} T{sub e}, and obtained ``Z/m`` spectra for the plasma ions (H{sup +}, H{sub 2}{sup +}, He{sup +}). Additional experiments confirmed the theoretical scalings of the f/{delta}f resolution with the applied electric field and magnetic field strengths. The instrument yielded an absolute level of resolution, f/{delta}f, of approximately 2.5 to 3 times the theoretical values. Finally, the results from the HCD are used to project operation on Alcator C-Mod.

  5. The TFTR E Parallel B Spectrometer for Mass and Energy Resolved Multi-Ion Charge Exchange Diagnostics

    SciTech Connect

    A.L. Roquemore; S.S. Medley

    1998-01-01

    The Charge Exchange Neutral Analyzer diagnostic for the Tokamak Fusion Test Reactor was designed to measure the energy distributions of both the thermal ions and the supra thermal populations arising from neutral-beam injection and ion cyclotron radio-frequency heating. These measurements yield the plasma ion temperature, as well as several other plasma parameters necessary to provide an understanding of the plasma condition and the performance of the auxiliary heating methods. For this application, a novel charge-exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory. The design and performance of this spectrometer is described in detail, including the effects of exposure of the microchannel plate detector to magnetic fields, neutrons, and tritium.

  6. A Low-Noise, Wideband Preamplifier for a Fourier-Transform Ion Cyclotron Resonance Mass Spectrometer

    PubMed Central

    Mathur, Raman; Knepper, Ronald W.; O'Connor, Peter B.

    2009-01-01

    FTMS performance parameters such as limits of detection, dynamic range, sensitivity, and even mass accuracy and resolution can be greatly improved by enhancing its detection circuit. An extended investigation of significant design considerations for optimal signal-to-noise ratio in an FTMS detection circuit are presented. A low noise amplifier for an FTMS is developed based on the discussed design rules. The amplifier has a gain of ≈ 3500 and a bandwidth of 10 kHz - 1 MHz corresponding to m/z range of 100 Da to 10 kDa (at 7 Tesla). The performance of the amplifier was tested on a MALDI-FTMS, and has demonstrated a 25-fold reduction in noise in a mass spectrum of C60 compared to that of a commercial amplifier. PMID:18029195

  7. Compact hydrogen/helium isotope mass spectrometer

    DOEpatents

    Funsten, Herbert O.; McComas, David J.; Scime, Earl E.

    1996-01-01

    The compact hydrogen and helium isotope mass spectrometer of the present invention combines low mass-resolution ion mass spectrometry and beam-foil interaction technology to unambiguously detect and quantify deuterium (D), tritium (T), hydrogen molecule (H.sub.2, HD, D.sub.2, HT, DT, and T.sub.2), .sup.3 He, and .sup.4 He concentrations and concentration variations. The spectrometer provides real-time, high sensitivity, and high accuracy measurements. Currently, no fieldable D or molecular speciation detectors exist. Furthermore, the present spectrometer has a significant advantage over traditional T detectors: no confusion of the measurements by other beta-emitters, and complete separation of atomic and molecular species of equivalent atomic mass (e.g., HD and .sup.3 He).

  8. DETERMINATION OF ION AND NEUTRAL LOSS COMPOSITIONS AND DECONVOLUTION OF PRODUCT ION MASS SPECTRA USING AN ORTHOGONAL ACCELERATION, TIME-OF-FLIGHT MASS SPECTROMETER AND AN ION CORRELATION PROGRAM

    EPA Science Inventory

    Exact masses of monoisotopic ions and the relative isotopic abundances (RIAs) of ions greater in mass by 1 and 2 Da than the monoisotopic ion are independent and complementary physical properties useful for istinguishing among ion compositions possible for a given nominal mass. U...

  9. Miniature Ion-Array Spectrometer

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    A figure is shown that depicts a proposed miniature ion-mobility spectrometer that would share many features of design and operation of the instrument described in another article. The main differences between that instrument and this one would lie in the configuration and mode of operation of the filter and detector electrodes. A filter electrode and detector electrodes would be located along the sides of a drift tube downstream from the accelerator electrode. These electrodes would apply a combination of (1) a transverse AC electric field that would effect differential transverse dispersal of ions and (2) a transverse DC electric field that would drive the dispersed ions toward the detector electrodes at different distances along the drift tube. The electric current collected by each detector electrode would be a measure of the current, and thus of the abundance of the species of ions impinging on that electrode. The currents collected by all the detector electrodes could be measured simultaneously to obtain continuous readings of abundances of species. The downstream momentum of accelerated ions would be maintained through neutralization on the electrodes; the momentum of the resulting neutral atoms would serve to expel gases from spectrometer, without need for a pump.

  10. Highly charged ion secondary ion mass spectroscopy

    DOEpatents

    Hamza, Alex V.; Schenkel, Thomas; Barnes, Alan V.; Schneider, Dieter H.

    2001-01-01

    A secondary ion mass spectrometer using slow, highly charged ions produced in an electron beam ion trap permits ultra-sensitive surface analysis and high spatial resolution simultaneously. The spectrometer comprises an ion source producing a primary ion beam of highly charged ions that are directed at a target surface, a mass analyzer, and a microchannel plate detector of secondary ions that are sputtered from the target surface after interaction with the primary beam. The unusually high secondary ion yield permits the use of coincidence counting, in which the secondary ion stops are detected in coincidence with a particular secondary ion. The association of specific molecular species can be correlated. The unique multiple secondary nature of the highly charged ion interaction enables this new analytical technique.

  11. A Thomson-type mass and energy spectrometer for characterizing ion energy distributions in a coaxial plasma gun operating in a gas-puff mode

    NASA Astrophysics Data System (ADS)

    Rieker, G. B.; Poehlmann, F. R.; Cappelli, M. A.

    2013-07-01

    Measurements of ion energy distribution are performed in the accelerated plasma of a coaxial electromagnetic plasma gun operating in a gas-puff mode at relatively low discharge energy (900 J) and discharge potential (4 kV). The measurements are made using a Thomson-type mass and energy spectrometer with a gated microchannel plate and phosphor screen as the ion sensor. The parabolic ion trajectories are captured from the sensor screen with an intensified charge-coupled detector camera. The spectrometer was designed and calibrated using the Geant4 toolkit, accounting for the effects on the ion trajectories of spatial non-uniformities in the spectrometer magnetic and electric fields. Results for hydrogen gas puffs indicate the existence of a class of accelerated protons with energies well above the coaxial discharge potential (up to 24 keV). The Thomson analyzer confirms the presence of impurities of copper and iron, also of relatively high energies, which are likely erosion or sputter products from plasma-electrode interactions.

  12. A Thomson-type mass and energy spectrometer for characterizing ion energy distributions in a coaxial plasma gun operating in a gas-puff mode.

    PubMed

    Rieker, G B; Poehlmann, F R; Cappelli, M A

    2013-07-01

    Measurements of ion energy distribution are performed in the accelerated plasma of a coaxial electromagnetic plasma gun operating in a gas-puff mode at relatively low discharge energy (900 J) and discharge potential (4 kV). The measurements are made using a Thomson-type mass and energy spectrometer with a gated microchannel plate and phosphor screen as the ion sensor. The parabolic ion trajectories are captured from the sensor screen with an intensified charge-coupled detector camera. The spectrometer was designed and calibrated using the Geant4 toolkit, accounting for the effects on the ion trajectories of spatial non-uniformities in the spectrometer magnetic and electric fields. Results for hydrogen gas puffs indicate the existence of a class of accelerated protons with energies well above the coaxial discharge potential (up to 24 keV). The Thomson analyzer confirms the presence of impurities of copper and iron, also of relatively high energies, which are likely erosion or sputter products from plasma-electrode interactions.

  13. A Thomson-type mass and energy spectrometer for characterizing ion energy distributions in a coaxial plasma gun operating in a gas-puff mode

    SciTech Connect

    Rieker, G. B.; Poehlmann, F. R.; Cappelli, M. A.

    2013-07-15

    Measurements of ion energy distribution are performed in the accelerated plasma of a coaxial electromagnetic plasma gun operating in a gas-puff mode at relatively low discharge energy (900 J) and discharge potential (4 kV). The measurements are made using a Thomson-type mass and energy spectrometer with a gated microchannel plate and phosphor screen as the ion sensor. The parabolic ion trajectories are captured from the sensor screen with an intensified charge-coupled detector camera. The spectrometer was designed and calibrated using the Geant4 toolkit, accounting for the effects on the ion trajectories of spatial non-uniformities in the spectrometer magnetic and electric fields. Results for hydrogen gas puffs indicate the existence of a class of accelerated protons with energies well above the coaxial discharge potential (up to 24 keV). The Thomson analyzer confirms the presence of impurities of copper and iron, also of relatively high energies, which are likely erosion or sputter products from plasma-electrode interactions.

  14. A Thomson-type mass and energy spectrometer for characterizing ion energy distributions in a coaxial plasma gun operating in a gas-puff mode

    PubMed Central

    Rieker, G. B.; Poehlmann, F. R.; Cappelli, M. A.

    2013-01-01

    Measurements of ion energy distribution are performed in the accelerated plasma of a coaxial electromagnetic plasma gun operating in a gas-puff mode at relatively low discharge energy (900 J) and discharge potential (4 kV). The measurements are made using a Thomson-type mass and energy spectrometer with a gated microchannel plate and phosphor screen as the ion sensor. The parabolic ion trajectories are captured from the sensor screen with an intensified charge-coupled detector camera. The spectrometer was designed and calibrated using the Geant4 toolkit, accounting for the effects on the ion trajectories of spatial non-uniformities in the spectrometer magnetic and electric fields. Results for hydrogen gas puffs indicate the existence of a class of accelerated protons with energies well above the coaxial discharge potential (up to 24 keV). The Thomson analyzer confirms the presence of impurities of copper and iron, also of relatively high energies, which are likely erosion or sputter products from plasma-electrode interactions. PMID:23983449

  15. Characterization of ion processes in a GC/DMS air quality monitor by integration of the instrument to a mass spectrometer.

    PubMed

    Limero, T F; Nazarov, E G; Menlyadiev, M; Eiceman, G A

    2015-02-07

    The air quality monitor (AQM), which included a portable gas chromatograph (GC) and a detector was interfaced to a mass spectrometer (MS) by introducing flow from the GC detector to the atmospheric pressure ion source of the MS. This small GC system, with a gas recirculation loop for carrier and detector make-up gases, comprised an inlet to preconcentrate volatile organic compounds (VOCs) in air, a thermal desorber before the GC column, a differential mobility spectrometer (DMS), and another DMS as an atmospheric pressure ionization source for the MS. Return flow to the internally recirculated air system of the AQM's DMS was replenished using purified air. Although ions and unreacted neutral vapors flowed from the detector through Viton® tubing into the source of the MS, ions were not detected in the MS without the auxillary ion source, (63)Ni as in the mobility detector. The GC-DMS-MS instrument provided a 3-D measurement platform (GC, DMS, and MS analysis) to explore the gas composition inside the GC-DMS recirculation loop and provide DMS-MS measurement of the components of a complex VOC mixture with performance significantly enhanced by mass-analysis, either with mass spectral scans or with an extracted ion chromatogram. This combination of a mobility spectrometer and a mass spectrometer was possible as vapors and ions are carried together through the DMS analyzer, thereby preserving the chromatographic separation efficiency. The critical benefit of this instrument concept is that all flows in and through the thoroughly integrated GC-DMS analyzer are kept intact allowing a full measure of the ion and vapor composition in the complete system. Performance has been evaluated using a synthetic air sample and a sample of airborne vapors in a laboratory. Capabilities and performance values are described using results from AQM-MS analysis of purified air, ambient air from a research laboratory in a chemistry building, and a sample of synthetic air of known composition

  16. Miniaturized GC/MS instrumentation for in situ measurements: micro gas chromatography coupled with miniature quadrupole array and paul ion trap mass spectrometers

    NASA Technical Reports Server (NTRS)

    Holland, P.; Chutjian, A.; Darrach, M.; Orient, O.

    2002-01-01

    Miniaturized chemical instrumentation is needed for in situ measurements in planetary exploration and other spaceflight applications where factors such as reduction in payload requirements and enhanced robustness are important. In response to this need, we are 'continuing to develop miniaturized GC/MS instrumentation which combines chemical separations by gas chromatography (GC) with mass spectrometry (MS) to provide positive identification of chemical compounds in complex mixtures of gases, such as those found in the International Space Station's cabin atmosphere. Our design approach utilizes micro gas chromatography components coupled with either a miniature quadrupole mass spectrometer array (QMSA) or compact, high-resolution Paul ion trap.

  17. Miniature Ion-Mobility Spectrometer

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    The figure depicts a proposed miniature ion-mobility spectrometer that would be fabricated by micromachining. Unlike prior ion-mobility spectrometers, the proposed instrument would not be based on a time-of-flight principle and, consequently, would not have some of the disadvantageous characteristics of prior time-of-flight ion-mobility spectrometers. For example, one of these characteristics is the need for a bulky carrier-gas-feeding subsystem that includes a shutter gate to provide short pulses of gas in order to generate short pulses of ions. For another example, there is need for a complex device to generate pulses of ions from the pulses of gas and the device is capable of ionizing only a fraction of the incoming gas molecules; these characteristics preclude miniaturization. In contrast, the proposed instrument would not require a carrier-gas-feeding subsystem and would include a simple, highly compact device that would ionize all the molecules passing through it. The ionization device in the proposed instrument would be a 0.1-micron-thick dielectric membrane with metal electrodes on both sides. Small conical holes would be micromachined through the membrane and electrodes. An electric potential of the order of a volt applied between the membrane electrodes would give rise to an electric field of the order of several megavolts per meter in the submicron gap between the electrodes. An electric field of this magnitude would be sufficient to ionize all the molecules that enter the holes. Ionization (but not avalanche arcing) would occur because the distance between the ionizing electrodes would be less than the mean free path of gas molecules at the operating pressure of instrument. An accelerating grid would be located inside the instrument, downstream from the ionizing membrane. The electric potential applied to this grid would be negative relative to the potential on the inside electrode of the ionizing membrane and would be of a magnitude sufficient to

  18. Simultaneous Transmission Mode Collision-Induced Dissociation and Ion/Ion Reactions for Top-Down Protein Identification/Characterization Using a Quadrupole/Time-of-Flight Tandem Mass Spectrometer

    PubMed Central

    Liu, Jian; Huang, Teng-Yi; McLuckey, Scott A.

    2009-01-01

    Simultaneous transmission mode collision-induced dissociation (CID) and ion/ion proton transfer reactions have been implemented on a quadrupole/time-of-flight (TOF) tandem mass spectrometer. Reagent anions were trapped in a pressurized quadrupole collision cell by applying appropriate DC voltages while multiply protonated protein precursor ions were injected into the collision cell at energies sufficient to give rise to CID. Intact precursor ions as well as fragment ions underwent ion/ion proton transfer reactions during their passage through the collision cell and on to an orthogonal acceleration TOF mass analyzer. The resulting product ion spectrum was then submitted to deconvolution to yield a “zero-charge” spectrum, which was then matched against in silico produced spectra derived from a protein database. Dramatic improvements in the scores associated with correct matches were obtained relative to CID data without benefit of ion/ion reactions for proteins as large as carbonic anhydrase (29 kDa). The parameters that most affect the extent of ion/ion proton transfer during transmission through the instrument include the number of anions stored in the collision cell, the amplitude of the radio-frequency trapping voltage, the voltage of the LINAC potential associated with the collision cell, and the collision gas pressure. This work demonstrates that it is possible to effect whole protein tandem mass spectrometry with simultaneous CID, ion/ion reactions, and mass analysis for high duty cycle top-down protein characterization. PMID:19281259

  19. Screening for DNA Adducts by Data-Dependent Constant Neutral Loss - Triple Stage (MS3) Mass Spectrometry with a Linear Quadrupole Ion Trap Mass Spectrometer

    PubMed Central

    Bessette, Erin E.; Goodenough, Angela K.; Langouët, Sophie; Yasa, Isil; Kozekov, Ivan D.; Spivack, Simon D.; Turesky, Robert J.

    2009-01-01

    A 2-dimensional linear quadrupole ion trap mass spectrometer (LIT/MS) was employed to simultaneously screen for DNA adducts of environmental, dietary, and endogenous genotoxicants, by data-dependent constant neutral loss scanning followed by triple-stage mass spectrometry (CNL-MS3). The loss of the deoxyribose (dR) from the protonated DNA adducts ([M+H-116]+) in the MS/MS scan mode triggered the acquisition of MS3 product ion spectra of the aglycone adducts [BH2+]. Five DNA adducts of the tobacco carcinogen 4-aminobiphenyl (4-ABP) were detected in human hepatocytes treated with 4-ABP, and three DNA adducts of the cooked-meat carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) were identified in the livers of rats exposed to MeIQx, by the CNL-MS3 scan mode. Buccal-cell DNA from tobacco smokers was screened for DNA adducts of various classes of carcinogens in tobacco smoke including 4-ABP, 2-amino-9H-pyrido[2,3-b]indole (AαC), and benzo[a]pyrene (BaP); the cooked-meat carcinogens MeIQx, AαC, and 2-amino-1-methyl-6-phenylmidazo[4,5-b]pyridine (PhIP); and the lipid peroxidation products acrolein (AC) and trans-4-hydroxynonenal (HNE). The CNL-MS3 scanning technique can be used to simultaneously screen for multiple DNA adducts derived from different classes of carcinogens, at levels of adduct modification approaching 1 adduct per 108 unmodified DNA bases, when 10 μg of DNA are employed for the assay. PMID:19086795

  20. Screening for DNA adducts by data-dependent constant neutral loss-triple stage mass spectrometry with a linear quadrupole ion trap mass spectrometer.

    PubMed

    Bessette, Erin E; Goodenough, Angela K; Langouët, Sophie; Yasa, Isil; Kozekov, Ivan D; Spivack, Simon D; Turesky, Robert J

    2009-01-15

    A two-dimensional linear quadrupole ion trap mass spectrometer (LIT/MS) was employed to simultaneously screen for DNA adducts of environmental, dietary, and endogenous genotoxicants, by data-dependent constant neutral loss scanning followed by triple-stage mass spectrometry (CNL-MS3). The loss of the deoxyribose (dR) from the protonated DNA adducts ([M + H - 116]+) in the MS/MS scan mode triggered the acquisition of MS3 product ion spectra of the aglycone adducts [BH2]+. Five DNA adducts of the tobacco carcinogen 4-aminobiphenyl (4-ABP) were detected in human hepatocytes treated with 4-ABP, and three DNA adducts of the cooked-meat carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) were identified in the livers of rats exposed to MeIQx, by the CNL-MS3 scan mode. Buccal cell DNA from tobacco smokers was screened for DNA adducts of various classes of carcinogens in tobacco smoke including 4-ABP, 2-amino-9H-pyrido[2,3-b]indole (AalphaC), and benzo[a]pyrene (BaP); the cooked-meat carcinogens MeIQx, AalphaC, and 2-amino-1-methyl-6-phenylmidazo[4,5-b]pyridine (PhIP); and the lipid peroxidation products acrolein (AC) and trans-4-hydroxynonenal (HNE). The CNL-MS3 scanning technique can be used to simultaneously screen for multiple DNA adducts derived from different classes of carcinogens, at levels of adduct modification approaching 1 adduct per 108 unmodified DNA bases, when 10 microg of DNA is employed for the assay.

  1. First signal from a broadband cryogenic preamplifier cooled by circulating liquid nitrogen in a 7 T Fourier transform ion cyclotron resonance mass spectrometer.

    PubMed

    Choi, Myoung Choul; Lee, Jeong Min; Lee, Se Gyu; Choi, Sang Hwan; Choi, Yeon Suk; Lee, Kyung Jae; Kim, SeungYong; Kim, Hyun Sik; Stahl, Stefan

    2012-12-18

    Despite the outstanding performance of Fourier transform ion cyclotron/mass spectrometry (FTICR/MS), the complexity of the cellular proteome or natural compounds presents considerable challenges. Sensitivity is a key performance parameter of a FTICR mass spectrometer. By improving this parameter, the dynamic range of the instrument can be increased to improve the detection signal of low-abundance compounds or fragment ion peaks. In order to improve sensitivity, a cryogenic detection system was developed by the KBSI (Korean Basic Science Institute) in collaboration with Stahl-Electronics (Mettenheim, Germany). A simple, efficient liquid circulation cooling system was designed and a cryogenic preamplifier implemented inside a FTICR mass spectrometer. This cooling system circulates a cryoliquid from a Dewar to the "liquid circulation unit" through a CF flange to cool a copper block and a cryopreamplifier; the cooling medium is subsequently exhausted into the air. The cryopreamplifier can be operated over a very wide temperature range, from room temperature to low temperature environments (4.2 K). First, ion signals detected by the cryopreamplifier using a circulating liquid nitrogen cooling system were observed and showed a signal-to-noise ratio (S/N) about 130% better than that obtained at room temperature.

  2. Imaging MS Methodology for More Chemical Information in Less Data Acquisition Time Utilizing a Hybrid Linear Ion Trap-Orbitrap Mass Spectrometer

    SciTech Connect

    Perdian, D. C.; Lee, Young Jin

    2010-11-15

    A novel mass spectrometric imaging method is developed to reduce the data acquisition time and provide rich chemical information using a hybrid linear ion trap-orbitrap mass spectrometer. In this method, the linear ion trap and orbitrap are used in tandem to reduce the acquisition time by incorporating multiple linear ion trap scans during an orbitrap scan utilizing a spiral raster step plate movement. The data acquisition time was decreased by 43-49% in the current experiment compared to that of orbitrap-only scans; however, 75% or more time could be saved for higher mass resolution and with a higher repetition rate laser. Using this approach, a high spatial resolution of 10 {micro}m was maintained at ion trap imaging, while orbitrap spectra were acquired at a lower spatial resolution, 20-40 {micro}m, all with far less data acquisition time. Furthermore, various MS imaging methods were developed by interspersing MS/MS and MSn ion trap scans during orbitrap scans to provide more analytical information on the sample. This method was applied to differentiate and localize structural isomers of several flavonol glycosides from an Arabidopsis flower petal in which MS/MS, MSn, ion trap, and orbitrap images were all acquired in a single data acquisition.

  3. Portable gas chromatograph-mass spectrometer

    DOEpatents

    Andresen, Brian D.; Eckels, Joel D.; Kimmons, James F.; Myers, David W.

    1996-01-01

    A gas chromatograph-mass spectrometer (GC-MS) for use as a field portable organic chemical analysis instrument. The GC-MS is designed to be contained in a standard size suitcase, weighs less than 70 pounds, and requires less than 600 watts of electrical power at peak power (all systems on). The GC-MS includes: a conduction heated, forced air cooled small bore capillary gas chromatograph, a small injector assembly, a self-contained ion/sorption pump vacuum system, a hydrogen supply, a dual computer system used to control the hardware and acquire spectrum data, and operational software used to control the pumping system and the gas chromatograph. This instrument incorporates a modified commercial quadrupole mass spectrometer to achieve the instrument sensitivity and mass resolution characteristic of laboratory bench top units.

  4. Portable gas chromatograph-mass spectrometer

    DOEpatents

    Andresen, B.D.; Eckels, J.D.; Kimmons, J.F.; Myers, D.W.

    1996-06-11

    A gas chromatograph-mass spectrometer (GC-MS) is described for use as a field portable organic chemical analysis instrument. The GC-MS is designed to be contained in a standard size suitcase, weighs less than 70 pounds, and requires less than 600 watts of electrical power at peak power (all systems on). The GC-MS includes: a conduction heated, forced air cooled small bore capillary gas chromatograph, a small injector assembly, a self-contained ion/sorption pump vacuum system, a hydrogen supply, a dual computer system used to control the hardware and acquire spectrum data, and operational software used to control the pumping system and the gas chromatograph. This instrument incorporates a modified commercial quadrupole mass spectrometer to achieve the instrument sensitivity and mass resolution characteristic of laboratory bench top units. 4 figs.

  5. Portable gas chromatograph-mass spectrometer

    SciTech Connect

    Andresen, B.D.; Eckels, J.D.; Kimmins, J.F.; Myers, D.W.

    1994-12-31

    A gas chromatograph-mass spectrometer (GC-MS) for use as a field portable organic chemical analysis instrument. The GC-MS is designed to be contained in a standard size suitcase, weighs less than 70 pounds, and requires less than 600 watts of electrical power at peak power (all systems on). The GC-MS includes: a conduction heated, forced air cooled small bore capillary gas chromatograph, a small injector assembly, a self-contained ion/sorption pump vacuum system, a hydrogen supply, a dual computer system used to control the hardware and acquire spectrum data, and operational software used to control the pumping system and the gas chromatograph. This instrument incorporates a modified commercial quadrupole mass spectrometer to achieve the instrument sensitivity and mass resolution characteristic of laboratory bench top units.

  6. COSIMA Mass Spectrometer for the ROSETTA Mission

    NASA Astrophysics Data System (ADS)

    Henkel, H.; Höfner, H.; Kissel, J.; Koch, A.

    2003-04-01

    The eries COmetary eries Secondary eries Ion eries Mass eries Analyzer (COSIMA) is a german contribution to ESA's ROSETTA mission. The COSIMA instrument has been built by vH&S as prime contractor, with contributions by the MPE in Garching and various institutes from Germany and abroad. COSIMA's principal investigator is Dr. Jochen Kissel, MPE. COSIMA will extend our knowledge about comets by analyzing the chemical composition of the dust from comet Wirtanen, which it will visit in 2011. COSIMA is a time-of-flight (TOF) mass spectrometer system. The cometary dust is collected on metal black surfaces of targets, which are exposed to space. There are 24 such targets stored in a manipulation unit. A target is moved by a miniaturized robotic arm either to exposure or into one of three analyze positions: In one position, a microscopic camera localizes dust grains on the target and calculates their coordinates. In another position, the chemistry station, targets are thermally treated to later analyze modifications by heat. The third, main position is the analyzing spot of the TOF spectrometer; here a pulsed primary ion beam with energy 8 keV partially ionizes the dust grain. The secondary ions are extracted by an electrostatic lens and accelerated to an energy of 1 keV. The ions travel through a drift tube free of electrical fields; they are reflected at its end by an electrostatic reflector, travel back through the same tube, and finally hit an ion detector (microsphere plate with discriminating amplifier). From the individual flight times of the secondary ions a time-of-flight spectrum is assembled, which corresponds to the mass spectrum of the analyzed grain. The primary ions are generated by a liquid-metal Indium source. An ion-optical system, consisting of a beam switch, lenses, chopper, buncher stages, and deflection plates, forms the focused primary ion pulse. An auxiliary Indium source is used for sputtering/cleaning the targets and serves for redundancy by a

  7. Enhancement of Compound Selectivity Using a Radio Frequency Ion-Funnel Proton Transfer Reaction Mass Spectrometer: Improved Specificity for Explosive Compounds.

    PubMed

    González-Méndez, Ramón; Watts, Peter; Olivenza-León, David; Reich, D Fraser; Mullock, Stephen J; Corlett, Clive A; Cairns, Stuart; Hickey, Peter; Brookes, Matthew; Mayhew, Chris A

    2016-11-01

    A key issue with any analytical system based on mass spectrometry with no initial separation of compounds is to have a high level of confidence in chemical assignment. This is particularly true for areas of security, such as airports, and recent terrorist attacks have highlighted the need for reliable analytical instrumentation. Proton transfer reaction mass spectrometry is a useful technology for these purposes because the chances of false positives are small owing to the use of a mass spectrometric analysis. However, the detection of an ion at a given m/z for an explosive does not guarantee that that explosive is present. There is still some ambiguity associated with any chemical assignment owing to the presence of isobaric compounds and, depending on mass resolution, ions with the same nominal m/z. In this article we describe how for the first time the use of a radio frequency ion-funnel (RFIF) in the reaction region (drift tube) of a proton transfer reaction-time-of-flight-mass spectrometer (PTR-ToF-MS) can be used to enhance specificity by manipulating the ion-molecule chemistry through collisional induced processes. Results for trinitrotoluene, dinitrotoluenes, and nitrotoluenes are presented to demonstrate the advantages of this new RFIF-PTR-ToF-MS for analytical chemical purposes.

  8. Direct and Sensitive Detection of CWA Simulants by Active Capillary Plasma Ionization Coupled to a Handheld Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Wolf, Jan-Christoph; Etter, Raphael; Schaer, Martin; Siegenthaler, Peter; Zenobi, Renato

    2016-07-01

    An active capillary plasma ionization (ACI) source was coupled to a handheld mass spectrometer (Mini 10.5; Aston Labs, West Lafayette, IN, USA) and applied to the direct gas-phase detection and quantification of chemical warfare agent (CWA) related chemicals. Complementing the discontinuous atmospheric pressure interface (DAPI) of the Mini 10.5 mass spectrometer with an additional membrane pump, a quasi-continuous sample introduction through the ACI source was achieved. Nerve agent simulants (three dialkyl alkylphosphonates, a dialkyl phosporamidate, and the pesticide dichlorvos) were detected at low gas-phase concentrations with limits of detection ranging from 1.0 μg/m3 to 6.3 μg/m3. Our results demonstrate a sensitivity enhancement for portable MS-instrumentation by using an ACI source, enabling direct, quantitative measurements of volatile organic compounds. Due to its high sensitivity, selectivity, low power consumption (<80 W) and weight (<13 kg), this instrumentation has the potential for direct on-site CWA detection as required by military or civil protection.

  9. Resonance activation and collision-induced-dissociation of ions using rectangular wave dipolar potentials in a digital ion trap mass spectrometer.

    PubMed

    Xu, Fuxing; Wang, Liang; Dai, Xinhua; Fang, Xiang; Ding, Chuan-Fan

    2014-04-01

    Collision-induced dissociation (CID) of ions by resonance activation in a quadrupole ion trap is usually accomplished by resonance exciting the ions to higher kinetic energy, whereby the high kinetic energy ions collide with a bath gas, such as helium or argon, inside the trap and dissociate to fragments. A new ion activation method using a well-defined rectangular wave dipolar potential formed by dividing down the trapping rectangular waveform is developed and examined herein. The mass-selected parent ions are resonance excited to high kinetic energies by simply changing the frequency of the rectangular wave dipolar potential and dissociation proceeds. A relationship between the ion mass and the activation waveform frequency is also identified and described. This highly efficient (CID) procedure can be realized by simply changing the waveform frequency of the dipolar potential, which could certainly simplify tandem mass spectrometry analysis methods.

  10. Mass spectrometer with magnetic pole pieces providing the magnetic fields for both the magnetic sector and an ion-type vacuum pump

    NASA Technical Reports Server (NTRS)

    Sieradski, L. M.; Giffin, C. E.; Nier, A. O. (Inventor)

    1976-01-01

    A mass spectrometer (MS) with unique magnetic pole pieces which provide a homogenous magnetic field across the gap of the MS magnetic sector as well as the magnetic field across an ion-type vacuum pump is disclosed. The pole pieces form the top and bottom sides of a housing. The housing is positioned so that portions of the pole pieces form part of the magnetic sector with the space between them defining the gap region of the magnetic sector, through which an ion beam passes. The pole pieces extend beyond the magnetic sector with the space between them being large enough to accommodate the electrical parts of an ion-type vacuum pump. The pole pieces which provide the magnetic field for the pump, together with the housing form the vacuum pump enclosure or housing.

  11. Advanced Mass Spectrometers for Hydrogen Isotope Analyses

    SciTech Connect

    Chastagner, P.

    2001-08-01

    This report is a summary of the results of a joint Savannah River Laboratory (SRL) - Savannah River Plant (SRP) ''Hydrogen Isotope Mass Spectrometer Evaluation Program''. The program was undertaken to evaluate two prototype hydrogen isotope mass spectrometers and obtain sufficient data to permit SRP personnel to specify the mass spectrometers to replace obsolete instruments.

  12. Comparison of the applicability of mass spectrometer ion sources using a polarity- molecular weight scattergram with a 600 sample in-house chemical library.

    PubMed

    Sugimura, Natsuhiko; Furuya, Asami; Yatsu, Takahiro; Shibue, Toshimichi

    2015-01-01

    To provide a practical guideline for the selection of a mass spectrometer ion source, we compared the applicability of three types of ion source: direct analysis in real time (DART), electrospray ionization (ESI) and fast atom bombardment (FAB), using an in-house high-resolution mass spectrometry sample library consisting of approximately 600 compounds. The great majority of the compounds (92%), whose molecular weights (MWs) were broadly distributed between 150 and 1000, were detected using all the ion sources. Nevertheless, some compounds were not detected using specific ion sources. The use of FAB resulted in the highest sample detection rate (>98%), whereas the detection rates obtained using DART and ESI were slightly lower (>96%). A scattergram constructed using MW and topological polar surface area (tPSA) as a substitute for molecular polarity showed that the performance of ESI was weak in the low-MW (<400), low-polarity (tPSA<60) area, whereas the performance of DART was weak in the high-MW (>800) area. These results might provide guidelines for the selection of ion sources for inexperienced mass spectrometry users.

  13. Performance of the Linear Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer (MOMA) Investigation on the 2018 Exomars Rover

    NASA Technical Reports Server (NTRS)

    Arevalo, Ricardo, Jr.; Brinckerhoff, William B.; Pinnick, Veronica T.; van Amerom, Friso H. W.; Danell, Ryan M.; Li, Xiang; Getty, Stephanie; Hovmand, Lars; Atanassova, Martina; Mahaffy, Paul R.; Chu, Zhiping; Goesmann, Fred; Steininger, Harald

    2014-01-01

    The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from degradation derived from cosmic radiation and/or oxidative chemical reactions. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. The MOMA investigation is led by the Max Planck Institute for Solar System Research (MPS) with the mass spectrometer subsystem provided by NASA GSFC. MOMA's linear ion trap mass spectrometer (ITMS) is designed to analyze molecular composition of: (i) gas evolved from pyrolyzed powder samples and separated in a gas chromatograph; and, (ii) ions directly desorbed from crushed solid samples at Mars ambient pressure, as enabled by a pulsed UV laser system, fast-actuating aperture valve and capillary ion inlet. Breadboard ITMS and associated electronics have been advanced to high end-to-end fidelity in preparation for flight hardware delivery to Germany in 2015.

  14. Utilizing artificial neural networks in MATLAB to achieve parts-per-billion mass measurement accuracy with a fourier transform ion cyclotron resonance mass spectrometer.

    PubMed

    Williams, D Keith; Kovach, Alexander L; Muddiman, David C; Hanck, Kenneth W

    2009-07-01

    Fourier transform ion cyclotron resonance mass spectrometry has the ability to realize exceptional mass measurement accuracy (MMA); MMA is one of the most significant attributes of mass spectrometric measurements as it affords extraordinary molecular specificity. However, due to space-charge effects, the achievable MMA significantly depends on the total number of ions trapped in the ICR cell for a particular measurement, as well as relative ion abundance of a given species. Artificial neural network calibration in conjunction with automatic gain control (AGC) is utilized in these experiments to formally account for the differences in total ion population in the ICR cell between the external calibration spectra and experimental spectra. In addition, artificial neural network calibration is used to account for both differences in total ion population in the ICR cell as well as relative ion abundance of a given species, which also affords mean MMA values at the parts-per-billion level.

  15. Automated mass spectrometer grows up

    SciTech Connect

    McInteer, B.B.; Montoya, J.G.; Stark, E.E.

    1984-01-01

    In 1980 we reported the development of an automated mass spectrometer for large scale batches of samples enriched in nitrogen-15 as ammonium salts. Since that time significant technical progress has been made in the instrument. Perhaps more significantly, administrative and institutional changes have permitted the entire effort to be transferred to the private sector from its original base at the Los Alamos National Laboratory. This has ensured the continuance of a needed service to the international scientific community as revealed by a development project at a national laboratory, and is an excellent example of beneficial technology transfer to private industry.

  16. Conformational ordering of biomolecules in the gas phase: nitrogen collision cross sections measured on a prototype high resolution drift tube ion mobility-mass spectrometer.

    PubMed

    May, Jody C; Goodwin, Cody R; Lareau, Nichole M; Leaptrot, Katrina L; Morris, Caleb B; Kurulugama, Ruwan T; Mordehai, Alex; Klein, Christian; Barry, William; Darland, Ed; Overney, Gregor; Imatani, Kenneth; Stafford, George C; Fjeldsted, John C; McLean, John A

    2014-02-18

    Ion mobility-mass spectrometry measurements which describe the gas-phase scaling of molecular size and mass are of both fundamental and pragmatic utility. Fundamentally, such measurements expand our understanding of intrinsic intramolecular folding forces in the absence of solvent. Practically, reproducible transport properties, such as gas-phase collision cross-section (CCS), are analytically useful metrics for identification and characterization purposes. Here, we report 594 CCS values obtained in nitrogen drift gas on an electrostatic drift tube ion mobility-mass spectrometry (IM-MS) instrument. The instrument platform is a newly developed prototype incorporating a uniform-field drift tube bracketed by electrodynamic ion funnels and coupled to a high resolution quadrupole time-of-flight mass spectrometer. The CCS values reported here are of high experimental precision (±0.5% or better) and represent four chemically distinct classes of molecules (quaternary ammonium salts, lipids, peptides, and carbohydrates), which enables structural comparisons to be made between molecules of different chemical compositions for the rapid "omni-omic" characterization of complex biological samples. Comparisons made between helium and nitrogen-derived CCS measurements demonstrate that nitrogen CCS values are systematically larger than helium values; however, general separation trends between chemical classes are retained regardless of the drift gas. These results underscore that, for the highest CCS accuracy, care must be exercised when utilizing helium-derived CCS values to calibrate measurements obtained in nitrogen, as is the common practice in the field.

  17. Conformational Ordering of Biomolecules in the Gas Phase: Nitrogen Collision Cross Sections Measured on a Prototype High Resolution Drift Tube Ion Mobility-Mass Spectrometer

    PubMed Central

    2014-01-01

    Ion mobility-mass spectrometry measurements which describe the gas-phase scaling of molecular size and mass are of both fundamental and pragmatic utility. Fundamentally, such measurements expand our understanding of intrinsic intramolecular folding forces in the absence of solvent. Practically, reproducible transport properties, such as gas-phase collision cross-section (CCS), are analytically useful metrics for identification and characterization purposes. Here, we report 594 CCS values obtained in nitrogen drift gas on an electrostatic drift tube ion mobility-mass spectrometry (IM-MS) instrument. The instrument platform is a newly developed prototype incorporating a uniform-field drift tube bracketed by electrodynamic ion funnels and coupled to a high resolution quadrupole time-of-flight mass spectrometer. The CCS values reported here are of high experimental precision (±0.5% or better) and represent four chemically distinct classes of molecules (quaternary ammonium salts, lipids, peptides, and carbohydrates), which enables structural comparisons to be made between molecules of different chemical compositions for the rapid “omni-omic” characterization of complex biological samples. Comparisons made between helium and nitrogen-derived CCS measurements demonstrate that nitrogen CCS values are systematically larger than helium values; however, general separation trends between chemical classes are retained regardless of the drift gas. These results underscore that, for the highest CCS accuracy, care must be exercised when utilizing helium-derived CCS values to calibrate measurements obtained in nitrogen, as is the common practice in the field. PMID:24446877

  18. Evaluation of Nickel and Chromium Ion Release During Fixed Orthodontic Treatment Using Inductively Coupled Plasma-Mass Spectrometer: An In Vivo Study

    PubMed Central

    Nayak, Rabindra S; Khanna, Bharti; Pasha, Azam; Vinay, K; Narayan, Anjali; Chaitra, K

    2015-01-01

    Background: Fixed orthodontic appliances with the use of stainless steel brackets and archwires made of nitinol have a corrosive potential in the oral environment. Nickel and chromium ions released from these appliances act as allergens apart from being cytotoxic, mutagenic and carcinogenic in smaller quantities in the range of nanograms. This study was done to evaluate the release of nickel and chromium ions from orthodontic appliances in the oral cavity using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Materials and Methods: Saliva samples from 30 orthodontic patients undergoing treatment with 0.022″ MBT mechanotherapy were collected prior to commencement of treatment, after initial aligning wires and after 10-12 months of treatment. Salivary nickel and chromium ion concentration was measured in parts per billion (ppb) using ICP-MS. Results: Mean, standard deviation and range were computed for the concentrations of ions obtained. Results analyzed using ANOVA indicated a statistically significant increase of 10.35 ppb in nickel ion concentration and 33.53 ppb in chromium ion concentration after initial alignment. The ionic concentration at the end of 10-12 months of treatment showed a statistically significant increase in of 17.92 ppb for chromium and a statistically insignificant decrease in nickel ion concentration by 1.58 ppb. Pearson’s correlation coefficient showed a positive correlation for an increase in nickel concentration after aligning, but not at the end of 10-12 months. A positive correlation was seen for an increase in chromium ion concentration at both time intervals. Conclusion: Nickel and chromium ion concentration in saliva even though below the recommended daily allowance should not be ignored in light of the new knowledge regarding effects of these ions at the molecular level and the allergic potential. Careful and detailed medical history of allergy is essential. Nickel free alternatives should form an essential part of an

  19. Surface-Induced Dissociation of Protein Complexes in a Hybrid Fourier Transform Ion Cyclotron Resonance Mass Spectrometer.

    PubMed

    Yan, Jing; Zhou, Mowei; Gilbert, Joshua D; Wolff, Jeremy J; Somogyi, Árpád; Pedder, Randall E; Quintyn, Royston S; Morrison, Lindsay J; Easterling, Michael L; Paša-Tolić, Ljiljana; Wysocki, Vicki H

    2017-01-03

    Mass spectrometry continues to develop as a valuable tool in the analysis of proteins and protein complexes. In protein complex mass spectrometry studies, surface-induced dissociation (SID) has been successfully applied in quadrupole time-of-flight (Q-TOF) instruments. SID provides structural information on noncovalent protein complexes that is complementary to other techniques. However, the mass resolution of Q-TOF instruments can limit the information that can be obtained for protein complexes by SID. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) provides ultrahigh resolution and ultrahigh mass accuracy measurements. In this study, an SID device was designed and successfully installed in a hybrid FT-ICR instrument in place of the standard gas collision cell. The SID-FT-ICR platform has been tested with several protein complex systems (homooligomers, a heterooligomer, and a protein-ligand complex, ranging from 53 to 85 kDa), and the results are consistent with data previously acquired on Q-TOF platforms, matching predictions from known protein interface information. SID fragments with the same m/z but different charge states are well-resolved based on distinct spacing between adjacent isotope peaks, and the addition of metal cations and ligands can also be isotopically resolved with the ultrahigh mass resolution available in FT-ICR.

  20. Calculations for Calibration of a Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Lee, Seungwon

    2008-01-01

    A computer program performs calculations to calibrate a quadrupole mass spectrometer in an instrumentation system for identifying trace amounts of organic chemicals in air. In the operation of the mass spectrometer, the mass-to-charge ratio (m/z) of ions being counted at a given instant of time is a function of the instantaneous value of a repeating ramp voltage waveform applied to electrodes. The count rate as a function of time can be converted to an m/z spectrum (equivalent to a mass spectrum for singly charged ions), provided that a calibration of m/z is available. The present computer program can perform the calibration in either or both of two ways: (1) Following a data-based approach, it can utilize the count-rate peaks and the times thereof measured when fed with air containing known organic compounds. (2) It can utilize a theoretical proportionality between the instantaneous m/z and the instantaneous value of an oscillating applied voltage. The program can also estimate the error of the calibration performed by the data-based approach. If calibrations are performed in both ways, then the results can be compared to obtain further estimates of errors.

  1. Characterizing a switching reagent ion chemical ionization high resolution time of flight mass spectrometer: Standard additions, External calibrations, and Inlet response during SOAS

    NASA Astrophysics Data System (ADS)

    Brophy, P.; Farmer, D.

    2013-12-01

    A high-resolution time of flight chemical ionization mass spectrometer (HRToF-CIMS) with switching reagent ion source and low pressure, gas-phase inlet was deployed during the 2013 Southern Oxidant and Aerosol Study (SOAS) in Brent, Alabama. Acetate chemistry was employed for the detection of small acids and iodine chemistry for the detection of peroxy acids. Switching between the two ion sources was found to be possible on less than ten minute time scales with minimal artifacts observed. Online calibrations for formic acid on both the acetate and iodine sources were performed every hour using both standard addition techniques as well as external standard calibrations; offline formic acid calibrations were also conducted. Inlet responses were investigated though a number of experiments finding that the inlet has minimal hysteresis and rapid response times.

  2. AN ION CORRELATION PROGRAM FOR DECONVOLUTING COMPOSITE MASS SPECTRA ACQUIRED USING A DIRECT SURFACE IONIZATION SOURCE INTERFACED TO A TIME-OF-FLIGHT MASS SPECTROMETER

    EPA Science Inventory

    The rapid sampling provided by the DART in ambient air will allow rapid delineation of areas of dispersed chemicals after natural or man-made disasters. Exact masses and RIAs of dimer, precursor, and product ions measured by the oa-TOFMS entered dinto the Ion Correlation Program...

  3. Lens system for a photo ion spectrometer

    DOEpatents

    Gruen, Dieter M.; Young, Charles E.; Pellin, Michael J.

    1990-01-01

    A lens system in a photo ion spectrometer for manipulating a primary ion beam and ionized atomic component. The atomic components are removed from a sample by a primary ion beam using the lens system, and the ions are extracted for analysis. The lens system further includes ionization resistant coatings for protecting the lens system.

  4. Lens system for a photo ion spectrometer

    DOEpatents

    Gruen, D.M.; Young, C.E.; Pellin, M.J.

    1990-11-27

    A lens system in a photo ion spectrometer for manipulating a primary ion beam and ionized atomic component is disclosed. The atomic components are removed from a sample by a primary ion beam using the lens system, and the ions are extracted for analysis. The lens system further includes ionization resistant coatings for protecting the lens system. 8 figs.

  5. Detection of Amines and Ammonia with an Ambient Pressure Mass Spectrometer using a Corona Discharge Ion Source, in an Urban Atmosphere and in a Teflon Film Chamber

    NASA Astrophysics Data System (ADS)

    Alves, M.; Hanson, D. R.; Grieves, C.; Ortega, J. V.

    2015-12-01

    Amines and ammonia are an important group of molecules that can greatly affect atmospheric particle formation that can go on to impact cloud formation and their scattering of thermal and solar radiation, and as a result human health and ecosystems. In this study, an Ambient Pressure Mass Spectrometer (AmPMS) that is selective and sensitive to molecules with a high proton affinity, such as amines, was coupled with a newly built corona discharge ion source. AmPMS was used to monitor many different nitrogenous compound that are found in an urban atmosphere (July 2015, Minneapolis), down to the single digit pmol/mol level. Simultaneous to this, a proton transfer mass spectrometer also sampled the atmosphere through an inlet within 20 m of the AmPMS inlet. In another set of studies, a similar AmPMS was attached to a large Teflon film chamber at the Atmospheric Chemistry Division at NCAR (August 2015, Boulder). Exploratory studies are planned on the sticking of amines to the chamber walls as well as oxidizing the amine and monitoring products. Depending on the success of these studies, results will be presented on the reversability of amine partitioning and mass balance for these species in the chamber.

  6. Ion mobility-mass spectrometry.

    PubMed

    Kanu, Abu B; Dwivedi, Prabha; Tam, Maggie; Matz, Laura; Hill, Herbert H

    2008-01-01

    This review article compares and contrasts various types of ion mobility-mass spectrometers available today and describes their advantages for application to a wide range of analytes. Ion mobility spectrometry (IMS), when coupled with mass spectrometry, offers value-added data not possible from mass spectra alone. Separation of isomers, isobars, and conformers; reduction of chemical noise; and measurement of ion size are possible with the addition of ion mobility cells to mass spectrometers. In addition, structurally similar ions and ions of the same charge state can be separated into families of ions which appear along a unique mass-mobility correlation line. This review describes the four methods of ion mobility separation currently used with mass spectrometry. They are (1) drift-time ion mobility spectrometry (DTIMS), (2) aspiration ion mobility spectrometry (AIMS), (3) differential-mobility spectrometry (DMS) which is also called field-asymmetric waveform ion mobility spectrometry (FAIMS) and (4) traveling-wave ion mobility spectrometry (TWIMS). DTIMS provides the highest IMS resolving power and is the only IMS method which can directly measure collision cross-sections. AIMS is a low resolution mobility separation method but can monitor ions in a continuous manner. DMS and FAIMS offer continuous-ion monitoring capability as well as orthogonal ion mobility separation in which high-separation selectivity can be achieved. TWIMS is a novel method of IMS with a low resolving power but has good sensitivity and is well intergrated into a commercial mass spectrometer. One hundred and sixty references on ion mobility-mass spectrometry (IMMS) are provided.

  7. TEMPO-Assisted Free Radical-Initiated Peptide Sequencing Mass Spectrometry (FRIPS MS) in Q-TOF and Orbitrap Mass Spectrometers: Single-Step Peptide Backbone Dissociations in Positive Ion Mode

    NASA Astrophysics Data System (ADS)

    Jang, Inae; Lee, Sun Young; Hwangbo, Song; Kang, Dukjin; Lee, Hookeun; Kim, Hugh I.; Moon, Bongjin; Oh, Han Bin

    2017-01-01

    The present study demonstrates that one-step peptide backbone fragmentations can be achieved using the TEMPO [2-(2,2,6,6-tetramethyl piperidine-1-oxyl)]-assisted free radical-initiated peptide sequencing (FRIPS) mass spectrometry in a hybrid quadrupole time-of-flight (Q-TOF) mass spectrometer and a Q-Exactive Orbitrap instrument in positive ion mode, in contrast to two-step peptide fragmentation in an ion-trap mass spectrometer (reference Anal. Chem. 85, 7044-7051 (30)). In the hybrid Q-TOF and Q-Exactive instruments, higher collisional energies can be applied to the target peptides, compared with the low collisional energies applied by the ion-trap instrument. The higher energy deposition and the additional multiple collisions in the collision cell in both instruments appear to result in one-step peptide backbone dissociations in positive ion mode. This new finding clearly demonstrates that the TEMPO-assisted FRIPS approach is a very useful tool in peptide mass spectrometry research.

  8. TEMPO-Assisted Free Radical-Initiated Peptide Sequencing Mass Spectrometry (FRIPS MS) in Q-TOF and Orbitrap Mass Spectrometers: Single-Step Peptide Backbone Dissociations in Positive Ion Mode.

    PubMed

    Jang, Inae; Lee, Sun Young; Hwangbo, Song; Kang, Dukjin; Lee, Hookeun; Kim, Hugh I; Moon, Bongjin; Oh, Han Bin

    2017-01-01

    The present study demonstrates that one-step peptide backbone fragmentations can be achieved using the TEMPO [2-(2,2,6,6-tetramethyl piperidine-1-oxyl)]-assisted free radical-initiated peptide sequencing (FRIPS) mass spectrometry in a hybrid quadrupole time-of-flight (Q-TOF) mass spectrometer and a Q-Exactive Orbitrap instrument in positive ion mode, in contrast to two-step peptide fragmentation in an ion-trap mass spectrometer (reference Anal. Chem. 85, 7044-7051 (30)). In the hybrid Q-TOF and Q-Exactive instruments, higher collisional energies can be applied to the target peptides, compared with the low collisional energies applied by the ion-trap instrument. The higher energy deposition and the additional multiple collisions in the collision cell in both instruments appear to result in one-step peptide backbone dissociations in positive ion mode. This new finding clearly demonstrates that the TEMPO-assisted FRIPS approach is a very useful tool in peptide mass spectrometry research. Graphical Abstract ᅟ.

  9. Measurement of carbon distribution in nuclear fuel pin cladding specimens by means of a secondary ion mass spectrometer

    NASA Astrophysics Data System (ADS)

    Bart, Gerhard; Aerne, Ernst Tino; Burri, Martin; Zwicky, Hans-Urs

    1986-11-01

    Cladding carburization during irradiation of advanced mixed uranium plutonium carbide fast breeder reactor fuel is possibly a life limiting fuel pin factor. The quantitative assessment of such clad carbon embrittlement is difficult to perform by electron microprobe analysis because of sample surface contamination, and due to the very low energy of the carbon K α X-ray transition. The work presented here describes a method developed at the Swiss Federal Institute for Reactor Research (EIR) to use shielded secondary ion mass spectrometry (SIMS) as an accurate tool to determine radial distribution profiles of carbon in radioactive stainless steel fuel pin cladding. Compared with nuclear microprobe analysis (NMA) [1], which is also an accurate method for carbon analysis, the SIMS method distinguishes itself by its versatility for simultaneous determination of additional impurities.

  10. Flow reactor and triple quadrupole mass spectrometer investigations of negative ion reactions involving nitric acid - Implications for atmospheric HNO3 detection by chemical ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Moehler, O.; Arnold, F.

    1991-07-01

    The ion-molecule reactions on which Active Chemical Ionization Mass Spectrometry (ACIMS) measurements of atmospheric nitric acid are based are presently subjected to product-ion distribution and rate coefficient measurements. The results obtained indicate that while previous stratospheric nitric acid measurements were not impared by collisional dissociation processes, these processes may have played a major role during previous tropospheric measurements: leading to an undereestimation of nitric acid concentrations. A novel ACIMS ion source has been developed in order to avoid these problems.

  11. Spectrometer for cluster ion beam induced luminescence

    SciTech Connect

    Ryuto, H. Sakata, A.; Takeuchi, M.; Takaoka, G. H.; Musumeci, F.

    2015-02-15

    A spectrometer to detect the ultra-weak luminescence originated by the collision of cluster ions on the surfaces of solid materials was constructed. This spectrometer consists of 11 photomultipliers with band-pass interference filters that can detect the luminescence within the wavelength ranging from 300 to 700 nm and of a photomultiplier without filter. The calibration of the detection system was performed using the photons emitted from a strontium aluminate fluorescent tape and from a high temperature tungsten filament. Preliminary measurements show the ability of this spectrometer to detect the cluster ion beam induced luminescence.

  12. A Mass Spectrometer Simulator in Your Computer

    ERIC Educational Resources Information Center

    Gagnon, Michel

    2012-01-01

    Introduced to study components of ionized gas, the mass spectrometer has evolved into a highly accurate device now used in many undergraduate and research laboratories. Unfortunately, despite their importance in the formation of future scientists, mass spectrometers remain beyond the financial reach of many high schools and colleges. As a result,…

  13. Tandem time-of-flight mass spectrometer for photodissociation of biopolymer ions generated by matrix-assisted laser desorption ionization (MALDI-TOF-PD-TOF) using a linear-plus-quadratic potential reflectron.

    PubMed

    Oh, Joo Yeon; Moon, Jeong Hee; Kim, Myung Soo

    2004-08-01

    A tandem time-of-flight mass spectrometer for the study of photodissociation of biopolymer ions generated by matrix-assisted laser desorption ionization was designed and constructed. A reflectron with linear and quadratic (LPQ) potential components was used. Characteristics of the LPQ reflectron and its utility as the second stage analyzer of the tandem mass spectrometer were investigated. Performance of the instrument was tested by observing photodissociation of [M + H](+) from angiotensin II, a prototype polypeptide. Quality of the photodissociation tandem mass spectrum was almost comparable to that of the post-source decay spectrum. Monoisotopic selection of the parent ion was possible, which was achieved through the ion beam-laser beam synchronization. General theoretical considerations needed for a successful photodissociation of large biopolymer ions are also presented.

  14. Miniaturised Time-of-Flight Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Rohner, U.; Benz, W.; Whitby, J. A.; Wurz, P.; Schulz, R.; Romstedt, J.

    2004-04-01

    Originally intended for the European Space Agency's BepiColombo mission to Mercury, we have built a series of highly miniaturised laser ablation time of flight mass spectrometers (LMS), suitable for in situ measurements of the elemental and isotopic composition of the surface of airless planetary bodies. The instruments will determine ma jor, minor, and trace element abundances in minerals on a spatial scale of 10 m, and will have sufficient dynamic range and mass resolution to perform useful isotopic measurements in favourable cases. Solid material is simultaneously evaporated and ionised by means of laser ablation, requiring intense pulsed laser radiation. Laser ablation was chosen as the sample introduction technique principally because of its high spatial resolution and the lack of any need for sample preparation. Advantages of the technique include simplicity of the resulting design, speed of measurement, and the ability for depth profiling (potentially important for a regolith in which mineral grains are coated with impact produced glass). Time of flight mass spectrometers are simple, robust devices that couple well to a pulsed ion source and we have previous experience of their construction for space flight, e.g. the ROSINA instrument suite for the ROSETTA mission. For BepiColombo, we have built two prototype instruments, one with a design mass of 500 g and a volume comparable to a beer can intended to be deployed on a static lander, and a smaller cigarettebox sized version with a design mass of 250 g, small enough to be integrated in a rover or robotic arm.

  15. Ion mobility spectrometer with virtual aperture grid

    SciTech Connect

    Pfeifer, Kent B.; Rumpf, Arthur N.

    2010-11-23

    An ion mobility spectrometer does not require a physical aperture grid to prevent premature ion detector response. The last electrodes adjacent to the ion collector (typically the last four or five) have an electrode pitch that is less than the width of the ion swarm and each of the adjacent electrodes is connected to a source of free charge, thereby providing a virtual aperture grid at the end of the drift region that shields the ion collector from the mirror current of the approaching ion swarm. The virtual aperture grid is less complex in assembly and function and is less sensitive to vibrations than the physical aperture grid.

  16. Miniature Focusing Time-of-Flight Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Kanik, Isik; Srivastava, Santosh

    2005-01-01

    An improved miniature time-of-flight mass spectrometer has been developed in a continuing effort to minimize the sizes, weights, power demands, and costs of mass spectrometers for such diverse applications as measurement of concentrations of pollutants in the atmosphere, detecting poisonous gases in mines, and analyzing exhaust gases of automobiles. Advantageous characteristics of this mass spectrometer include the following: It is simple and rugged. Relative to prior mass spectrometers, it is inexpensive to build. There is no need for precise alignment of its components. Its mass range is practically unlimited Relative to prior mass spectrometers, it offers high sensitivity (ability to measure relative concentrations as small as parts per billion). Its resolution is one dalton (one atomic mass unit). An entire mass spectrum is recorded in a single pulse. (In a conventional mass spectrometer, a spectrum is recorded mass by mass.) The data-acquisition process takes only seconds. It is a lightweight, low-power, portable instrument. Although time-of-flight mass spectrometers (TOF-MSs) have been miniaturized previously, their performances have not been completely satisfactory. An inherent adverse effect of miniaturization of a TOF-MS is a loss of resolution caused by reduction of the length of its flight tube. In the present improved TOF-MS, the adverse effect of shortening the flight tube is counteracted by (1) using charged-particle optics to constrain ion trajectories to the flight-tube axis while (2) reducing ion velocities to increase ion flight times. In the present improved TOF-MS, a stream of gas is generated by use of a hypodermic needle. The stream of gas is crossed by an energy-selected, pulsed beam of electrons (see Figure 1). The ions generated by impingement of the electrons on the gas atoms are then focused by three cylindrical electrostatic lenses, which constitute a segmented flight tube. After traveling along the flight tube, the ions enter a charged

  17. Composition of hot ions /0.1-16 keV/e/ as observed by the GEOS and ISEE mass spectrometers and inferences for the origin and circulation of magnetospheric plasmas

    NASA Technical Reports Server (NTRS)

    Balsiger, H.

    1981-01-01

    The composition of hot magnetospheric plasma through different regions of the magnetosphere is described on the basis of mass spectrometer measurements by the GEOS 1, GEOS 2, and ISEE-1 spacecraft. Coordinated composition measurements on the different spacecraft also provide information on the spatial and temporal characteristics of the plasma during storms. Data on ion origins are also provided.

  18. Composition of hot ions /0. 1-16 keV/e/ as observed by the GEOS and ISEE mass spectrometers and inferences for the origin and circulation of magnetospheric plasmas

    SciTech Connect

    Balsiger, H.

    1981-01-01

    The composition of hot magnetospheric plasma through different regions of the magnetosphere is described on the basis of mass spectrometer measurements by the GEOS 1, GEOS 2, and ISEE-1 spacecraft. Coordinated composition measurements on the different spacecraft also provide information on the spatial and temporal characteristics of the plasma during storms. Data on ion origins are also provided.

  19. The PNL high-transmission three-stage mass spectrometer

    NASA Astrophysics Data System (ADS)

    Stoffels, J. J.; Ells, D. R.; Bond, L. A.; Freedman, P. A.; Tattersall, B. N.; Lagergren, C. R.

    1992-12-01

    We have constructed a three-stage isotope-ratio mass spectrometer of unique ion-optical design that achieves high ion transmission efficiency and high abundance sensitivity. The spectrometer has tandem 90 deg deflection magnets with boundaries 18 deg off normal. The magnet drift lengths are 1.48 times the 27-cm radius of deflection. This extended geometry gives a mass dispersion equivalent to a 40-cm-radius magnet with normal boundaries. The first magnet renders the ion beam parallel in the vertical plane and provides a focus in the horizontal plane of mass dispersion. The second magnet brings the beam to a stigmatic focus. This novel ion-optical design gives 100 percent transmission without the need for intermediate focusing lenses. It also provides a 16 percent increase in mass resolution over the traditional tandem geometry with normal magnet boundaries. Complete transmission of ions is maintained through a third-stage cylindrical electric sector of 38-cm radius, which provides increased isotope-abundance sensitivity. The isotope-abundance sensitivity of the new mass spectrometer is an order of magnitude better than similar instruments with normal magnet boundaries. This is because the vertical focusing of the ion beam prevents ion scattering from the top and bottom of the flight tube. The measured values of the isotope-abundance sensitivity one-half mass unit away from the rhenium ion peaks at masses 185 and 187 are M - 1/2 = (6.5 +/- 0.5)(10)(exp -10) and M + 1/2 = (3.1 +/- 0.8)(10)(exp -10). By extrapolation, the uranium isotope-abundance sensitivity is M - 1 = 1(10)(exp -10). Construction of the instrument was facilitated by using standard commercial mass spectrometer components.

  20. The PNL high-transmission three-stage mass spectrometer

    SciTech Connect

    Stoffels, J.J.; Ells, D.R.; Bond, L.A.; Freedman, P.A.; Tattersall, B.N.; Lagergren, C.R.

    1992-12-01

    We have constructed a three-stage isotope-ratio mass spectrometer of unique ion-optical design that achieves high ion transmission efficiency and high abundance sensitivity. The spectrometer has tandem 90{degrees} -deflection magnets with boundaries 18{degrees} off normal. The magnet drift lengths are 1.48 times the 27-cm radius of deflection. This extended geometry gives mass dispersion equivalent to a 40-cm-radius magnet with normal boundaries. The first magnet renders the ion beam parallel in the vertical plane and provides a focus in the horizontal plane of mass dispersion. The second magnet brings the beam to a stigmatic focus. This novel ion-optical design gives 100% transmission without the need for intermediate focusing lenses. It also provides a 16% increase in mass resolution over the traditional tandem geometry with normal magnet boundaries. Complete transmission of ions is maintained through a third-stage cylindrical electric sector of 38-cm radius, which provides increased isotope-abundance sensitivity. The isotope-abundance sensitivity of the new mass spectrometer is an order of magnitude better than similar instruments with normal magnet boundaries. This is because the vertical focusing of the ion beam prevents ion scattering from the top and bottom of the flight tube. The measured values of the isotope-abundance sensitivity one-half mass unit away from the rhenium ion peaks at masses 185 and 187 are M {minus} 1/2 = (6.5 {plus_minus} 0.5){times} 0{sup {minus}10} M + 1/2 = (3.1 {plus_minus} 0.8) {times} 10{sup {minus}10}. By extrapolation, the uranium isotope-abundance sensitivity is m {minus} 1 = 1 {times} 10{sup {minus}10}. Construction of the instrument was facilitated by using standard commercial mass spectrometer components.

  1. The PNL high-transmission three-stage mass spectrometer

    SciTech Connect

    Stoffels, J.J.; Ells, D.R.; Bond, L.A. ); Freedman, P.A.; Tattersall, B.N. ); Lagergren, C.R. )

    1992-12-01

    We have constructed a three-stage isotope-ratio mass spectrometer of unique ion-optical design that achieves high ion transmission efficiency and high abundance sensitivity. The spectrometer has tandem 90[degrees] -deflection magnets with boundaries 18[degrees] off normal. The magnet drift lengths are 1.48 times the 27-cm radius of deflection. This extended geometry gives mass dispersion equivalent to a 40-cm-radius magnet with normal boundaries. The first magnet renders the ion beam parallel in the vertical plane and provides a focus in the horizontal plane of mass dispersion. The second magnet brings the beam to a stigmatic focus. This novel ion-optical design gives 100% transmission without the need for intermediate focusing lenses. It also provides a 16% increase in mass resolution over the traditional tandem geometry with normal magnet boundaries. Complete transmission of ions is maintained through a third-stage cylindrical electric sector of 38-cm radius, which provides increased isotope-abundance sensitivity. The isotope-abundance sensitivity of the new mass spectrometer is an order of magnitude better than similar instruments with normal magnet boundaries. This is because the vertical focusing of the ion beam prevents ion scattering from the top and bottom of the flight tube. The measured values of the isotope-abundance sensitivity one-half mass unit away from the rhenium ion peaks at masses 185 and 187 are M [minus] 1/2 = (6.5 [plus minus] 0.5)[times] 0[sup [minus]10] M + 1/2 = (3.1 [plus minus] 0.8) [times] 10[sup [minus]10]. By extrapolation, the uranium isotope-abundance sensitivity is m [minus] 1 = 1 [times] 10[sup [minus]10]. Construction of the instrument was facilitated by using standard commercial mass spectrometer components.

  2. Application and field test of a mobile thermal desorption - single photon ionization - ion trap mass spectrometer (TD-SPI-ITMS) for trace detection of security relevant substances

    NASA Astrophysics Data System (ADS)

    Schramm, Elisabeth; Heindl, Thomas; Hölzer, Jasper; McNeish, Alexander; Puetz, Michael; Ries, Hermann; Schall, Patricia; Schulte-Ladbeck, Rasmus; Schultze, Rainer; Sklorz, Martin; Spieker, Gerd; Trebbe, Roman; Ulrich, Andreas; Wieser, Jochen; Zimmermann, Ralf

    2009-05-01

    The objective of this accomplished project funded by the German BMBF was to develop a single photon ionization ion trap mass spectrometer (SPI-ITMS) for detection of security relevant substances in complex matrices at low concentrations. The advantage of such a soft ionization technique is a reduction of target ion fragmentation allowing identification of signals from complex matrices and enabling MS/MS capability. To obtain low detection limits, the applied photon energy has to be below the ionization potential (IP) of the bulk matrix components. Therefore, photon energies between 8 eV (155 nm) and 12 eV (103 nm) are necessary which was achieved with newly developed electron beam excimer lamps (EBEL). They generate light at different wavelengths depending on the selected rare gas emitting wavelengths adapted to the analyzed substances. So, e.g. with a krypton-EBEL with 8.4 eV photon energy most narcotics can be ionized without notable fragmentation. Due to their higher IPs, EBEL with higher photon energy have to be used for most explosives. Very low false-positive and false-negative rates have been achieved using MS/MS studies. First field tests of a demonstrator provided the proof of principle.

  3. Determination of the abundance of delta15N in nitrate ion in contaminated groundwater samples using an elemental analyzer coupled to a mass spectrometer.

    PubMed

    Ogawa, Y; Nishikawa, M; Nakasugi, O; Ii, H; Hirata, T

    2001-07-01

    A rapid method for measuring the delta15N of nitrate ion in water samples using an isotope ratio mass spectrometer coupled to an elemental analyzer system (EA-MS) was investigated. The water should be removed from the analytical sample before measurement with this system. We investigated the application of a super-absorbent polymer resin powder to various water samples. Each 1 mg of polymer resin powder can absorb about 50-100 mg of solution depending on the concentrations of major ions. Only samples which contain more than 100 mg l(-1) of nitrate-nitrogen are suitable to be absorbed by the polymer resin for the determination of delta15N of nitrate. Preconcentration by rotary evaporation was necessary for dilute samples but the temperature should be kept below 60 degrees C. The polymer resin (about 8 mg) containing the nitrate was directly analyzed using an EA-MS after being oven-dried at 80 degrees C. Good accuracy (precision +/- 0.3%) for delta15N measurements of nitrate-nitrogen in a sample without any isotope fractionation effects during pre-treatment was observed. Results for delta15N of nitrate in contaminated groundwater samples collected in the spring at a tea plantation area in Shizuoka, Japan, were from 9.8 to 10.6%, which were close to the delta15N abundance in organic fertilizers.

  4. On-line measurements of α-pinene ozonolysis products using an atmospheric pressure chemical ionisation ion-trap mass spectrometer

    NASA Astrophysics Data System (ADS)

    Warscheid, Bettina; Hoffmann, Thorsten

    An on-line technique to investigate complex organic oxidation reactions in environmental chamber experiments is presented. The method is based on the direct introduction of the chamber air into an atmospheric pressure ion source of a commercial ion-trap mass spectrometer. To demonstrate the analytical potential of the method (atmospheric pressure chemical ionisation/mass spectrometry, APCI/MS), the ozonolysis of α-pinene was investigated in a series of experiments performed in various sized reaction chambers at atmospheric pressure and 296 K in synthetic air. Investigations were focussed on the influence of the water vapour concentration on the formation of the predominant oxidation product, pinonaldehyde, derived from the α-pinene/ozone reaction. Quantification of pinonaldehyde was achieved by conducting a standard addition technique. The molar yield of pinonaldehyde was found to depend strongly on the actual water vapour concentration between <1 and 80% relative humidity. Starting with an average yield of 0.23±0.05 at dry conditions, pinonaldehyde formation was approximately doubled by reaching a yield of 0.53±0.05 at a relative humidity of around 60%. Furthermore, the formation mechanism of pinonaldehyde was investigated in greater detail using isotopically labelled water. Applying on-line APCI/MS, pinonaldehyde formation under incorporation of 18O was observed, strongly supporting the reaction of the stabilised Criegee radical with water in the gas phase as suggested by Alvarado et al. (Journal of Geophysical Research 103 (1998) 25541-25551). Furthermore, the mass spectra recorded on-line were used to perform a semi-quantitative estimation of the decomposition pathway of the primary ozonide, indicating a branching ratio of 0.35/0.65.

  5. Mass spectrometer vacuum housing and pumping system

    DOEpatents

    Coutts, Gerald W.; Bushman, John F.; Alger, Terry W.

    1996-01-01

    A vacuum housing and pumping system for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof.

  6. Mass spectrometer vacuum housing and pumping system

    DOEpatents

    Coutts, G.W.; Bushman, J.F.; Alger, T.W.

    1996-07-23

    A vacuum housing and pumping system is described for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof. 7 figs.

  7. Gas sampling system for a mass spectrometer

    DOEpatents

    Taylor, Charles E; Ladner, Edward P

    2003-12-30

    The present invention relates generally to a gas sampling system, and specifically to a gas sampling system for transporting a hazardous process gas to a remotely located mass spectrometer. The gas sampling system includes a capillary tube having a predetermined capillary length and capillary diameter in communication with the supply of process gas and the mass spectrometer, a flexible tube surrounding and coaxial with the capillary tube intermediate the supply of process gas and the mass spectrometer, a heat transfer tube surrounding and coaxial with the capillary tube, and a heating device in communication the heat transfer tube for substantially preventing condensation of the process gas within the capillary tube.

  8. Strategic Characteristics of Dynamics Explorer. 1. Retarding Ion Mass Spectrometer and the Consequences for Core Plasma Measurements

    DTIC Science & Technology

    1989-09-14

    appears. This plasma, combined with an oxygen component inferred from measurements by the High Altitude Plasma Instrument (HAPI). comprise an unusually...Winningham, J. L. Burch, W. K. Peterson, J. H. Waite, and D. R. Weimer, Enhanced ion outflows measured by the DE 1 high - altitude plasma instrument in the

  9. Measuring Gas-Phase Basicities of Amino Acids Using an Ion Trap Mass Spectrometer: A Physical Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Sunderlin, Lee S.; Ryzhov, Victor; Keller, Lanea M. M.; Gaillard, Elizabeth R.

    2005-01-01

    An experiment is performed to measure the relative gas-phase basicities of a series of five amino acids to compare the results to literature values. The experiments use the kinetic method for deriving ion thermochemistry and allow students to perform accurate measurements of thermodynamics in a relatively short time.

  10. Mass Spectrometer for Airborne Micro-Organisms

    NASA Technical Reports Server (NTRS)

    Sinha, M. P.; Friedlander, S. K.

    1986-01-01

    Bacteria and other micro-organisms identified continously with aid of new technique for producing samples for mass spectrometer. Technique generates aerosol of organisms and feeds to spectrometer. Given species of organism produces characteristic set of peaks in mass spectrum and thereby identified. Technique useful for monitoring bacterial makeup in environmental studies and in places where cleanliness is essential, such as hospital operating rooms, breweries, and pharmaceutical plants.

  11. Formation of solvated ions in the atmospheric interface of an electrospray ionization triple-quadrupole mass spectrometer.

    PubMed

    Schlosser, Gitta; Takáts, Zoltán; Vékey, Károly

    2003-12-01

    A simple method capable of generating and investigating various solvent clusters and solvated ions was developed. The technique opens a door to studying these complexes on commercially available instruments. Formation of the desired solvated ion in the gas phase was achieved by introducing the appropriate volatile solvent vapour into the curtain gas stream. Capabilities of the technique are illustrated by generating alkali, alkaline earth and transition metal cations solvated by various volatile compounds such as water, methanol and acetonitrile. Depending on the ligands and on the experimental conditions, clusters of 2-100 molecules may be observed. Isotope labelling suggests that these are formed by a re-solvation process in the curtain gas region.

  12. Multiphoton Ionization of Laser-Desorbed Neutral Molecules in a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

    DTIC Science & Technology

    1990-05-19

    dissociates when irradiated with a gated pulse of light from a continuous wave carbon dioxide laser , forming two fragment ions at m/z = 200 and 171...this manner to laser photodissociation in a unique 3- laser experiment in which a third (gated, continuous- wave (cw) CO) laser has been used to...pathway shown in Figure 1), thus allowing the beam to travel through the center of the cell. Typical UV laser pulse energies were on the order of 50-100

  13. Mass spectrometry and inhomogeneous ion optics

    NASA Technical Reports Server (NTRS)

    White, F. A.

    1973-01-01

    Work done in several areas to advance the state of the art of magnetic mass spectrometers is described. The calculations and data necessary for the design of inhomogeneous field mass spectrometers, and the calculation of ion trajectories through such fields are presented. The development and testing of solid state ion detection devices providing the capability of counting single ions is discussed. New techniques in the preparation and operation of thermal-ionization ion sources are described. Data obtained on the concentrations of copper in rainfall and uranium in air samples using the improved thermal ionization techniques are presented. The design of a closed system static mass spectrometer for isotopic analyses is discussed. A summary of instrumental aspects of a four-stage mass spectrometer comprising two electrostatic and two 90 deg. magnetic lenses with a 122-cm radius used to study the interaction of ions with solids is presented.

  14. A field measurement based scaling approach for quantification of major ions, organic carbon, and elemental carbon using a single particle aerosol mass spectrometer

    NASA Astrophysics Data System (ADS)

    Zhou, Yang; Huang, X. H. Hilda; Griffith, Stephen M.; Li, Mei; Li, Lei; Zhou, Zhen; Wu, Cheng; Meng, Junwang; Chan, Chak K.; Louie, Peter K. K.; Yu, Jian Zhen

    2016-10-01

    Single Particle Aerosol Mass Spectrometers (SPAMS) have been increasingly deployed for aerosol studies in Asia. To date, SPAMS is most often used to provide unscaled information for both the size and chemical composition of individual particles. The instrument's lack of accuracy is primarily due to only a fraction of particles being detected after collection, and the instrumental sensitivity is un-calibrated for various chemical species in mixed ambient aerosols. During a campaign from January to April 2013 at a coastal site in Hong Kong, the particle number information and ion intensity of major PM2.5 components collected by SPAMS were scaled by comparing with collocated bulk PM2.5 measurements of hourly or higher resolution. The bulk measurements include PM2.5 mass by a SHARP 5030 Monitor, major ions by a Monitor for Aerosols & Gases in ambient Air (MARGA), and organic carbon (OC) and elemental carbon (EC) by a Sunset OCEC analyzer. During the data processing, both transmission efficiency (scaled with the Scanning Mobility Particle Sizer) and hit efficiency conversion were considered, and component ion intensities quantified as peak area (PA) and relative peak area (RPA) were analyzed to track the performance. The comparison between the scaled particle mass assuming a particle density of 1.9 g cm-3 from SPAMS and PM2.5 concentration showed good correlation (R2 = 0.81) with a slope of 0.814 ± 0.004. Regression analysis results suggest an improved scaling performance using RPA compared with PA for most of the major PM2.5 components, including sulfate, nitrate, potassium, ammonium, OC and EC. Thus, we recommend preferentially scaling these species using the RPA. For periods of high K+ concentrations (>1.5 μg m-3), under-estimation of K+ by SPAMS was observed due to exceeding the dynamic range of the acquisition board. When only applying the hit efficiency correction, data for sulfate, nitrate, ammonium, potassium and OC were in reasonably good correlation (R2 = 0

  15. Ion Composition in Titan's Exosphere from the Cassini Plasma Spectrometer

    NASA Astrophysics Data System (ADS)

    Woodson, A.; Smith, H. T.; Johnson, R. E.

    2013-12-01

    A primary goal of the Cassini mission has been to characterize the complex interaction between Saturn's magnetosphere and Titan's ionosphere. To this end, the Cassini spacecraft carries two instruments-the Ion and Neutral Mass Spectrometer (INMS) and the Cassini Plasma Spectrometer (CAPS)-capable of energy- and mass-analysis. The Ion Mass Spectrometer (IMS), one of three instruments composing CAPS, is designed to characterize diffuse plasmas throughout the magnetosphere while the INMS is optimized for measurements within Titan's upper atmosphere. As such, mass-resolved ion compositions confirming a variety of hydrocarbons and nitriles have been extracted from INMS data for numerous Titan encounters. Similar analysis of IMS data, however, has largely been resolution-limited to the identification of 'light' and 'heavy' ion groups in the wake. Herein we present a technique for extracting Dalton-resolved ion compositions from IMS spectra acquired below ~5 Titan radii. The method is then applied to data from the T40 encounter and the resulting relative abundances compared with those derived from the INMS data for the same encounter.

  16. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion trap mass spectrometer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PC. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PC. This approach is comprised of two mass spectr...

  17. UTILITY OF THREE TYPES OF MASS SPECTROMETERS FOR DETERMINING ELEMENTAL COMPOSITIONS OF IONS FORMED FROM CHROMATOGRAPHICALLY SEPARATED COMPOUNDS

    EPA Science Inventory

    Sponsor Referee: Douglas F. Barofsky, Oregon State University Concentration factors of 1000 and more reveal dozens of compounds in extracts of water supplies. Library mass spectra for most of these compounds are not available, and alternative means of identification are needed. D...

  18. Direct peel monitoring of xenobiotics in fruit by direct analysis in real time coupled to a linear quadrupole ion trap-orbitrap mass spectrometer.

    PubMed

    Farré, Marinella; Picó, Yolanda; Barceló, Damià

    2013-03-05

    Study of xenobiotics present in fruit peel by exposing it (without any pretreatment) to direct analysis in real time coupled to a high-resolution orbitrap mass spectrometer (DART-HRMS) is reported for the first time. Variables such as DART gas heater temperature and pressure, source-to-MS distance, and sample velocity are investigated. The analysis of one sample by DART-MS lasts ca. 1 min, and the benefits of both high-resolution and tandem mass spectrometry to elucidate nontarget or unknown compounds are combined. Identification of postharvest fungicides, antioxidants, and sugars in fruit peel is performed in the positive ion mode. A possible elemental formula is suggested for marker components. The lowest imazalil concentration that could be detected by this system is 1 ng (equivalent to a concentration of ca. 300 μg kg(-1)), which is well below the maximum residue limit. For oranges and apples, direct peel exposition demonstrated good interday precision (within 20% for any concentration) and proper linearity (R(2) ≥ 0.99), with a dynamic range from 1 to 2500 ng for apple. A comparison of the results obtained using the direct peel screening DART-based method is made with those obtained by DART analysis of solvent extracts, as well as those obtained analyzing these extracts by ultrahigh-performance liquid chromatography orbitrap mass spectrometry (UHPLC-Orbitrap). The results are in good agreement. Thus, the proposed method proves to be quantitatively accurate with indisputable identification specificity. As an independent method, the approach of direct scanning of peel is of high interest and of potential future within food analysis to guarantee safety, quality, and authenticity.

  19. High-performance double-focusing mass spectrometer

    NASA Technical Reports Server (NTRS)

    Nier, A. O.; Schlutter, D. J.

    1985-01-01

    Double focusing was first employed when mass spectrometers of a simpler design were not capable any longer to satisfy increasing demands in mass spectroscopy. One of the successful instruments of the 1930's was the mass spectrometer designed by Mattauch and Herzog (1934). The compactness of the Mattauch-Herzog geometry became particularly important in connection with studies involving the employment of rockets, satellites, or space probes. Another advantage of the considered spectrometer is related to the capability of measuring several masses of ions simultaneously. The instrument design was, therefore adopted for some rocket flights to the upper atmosphere, the investigation of the upper atmosphere of Mars, and for studying the upper atmosphere of Venus. Attention is given to laboratory applications involving the instrument in a somewhat enlarged version, and aspects of instrument operation and performance.

  20. Dynamics Explorer 1, retarding ion mass spectrometer summary spectrograms: 81/280 to 81/365 spin-time spectrograms for H(+), He(+), O(+), N(+), O(++), M/Z=2, and molecular ions

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Retarding Ion Mass Spectrometer (RIMS) experiment onboard the Dynamics Explorer 1 (DE 1) satellite was designed to perform energy and mass-per-charge analysis on low-energy ions (less than 50 eV) with mass/charge ratios ranging from 1 to 40 amu/Z. The DE 1 satellite, carrying the RIMS experiment, was launched into an elliptical polar orbit on August 3, 1981. The approximately 7.5 hour orbit has perigee of 675 km altitude and apogee of 24,875 km altitude. This document, as well as those that follow in this series, contains summary RIMS data spectrograms for each orbit for which RIMS data are available. The RIMS instrument began returning science data on day 280 of 1981 and continued to return usable data until the end of the DE mission in March 1991. It should be noted that studies of the RIMS data set should be conducted only with a thorough awareness of the material described in the introduction section presented here, or in collaboration with a scientist familiar with RIMS data analysis.

  1. Dynamics Explorer 1, retarding ion mass spectrometer summary spectrograms-82/110 to 82/229 spin-time spectrograms for H(+), He(+), O(+), N(+), O(++), M/Z = 2, and molecular ions

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The retarding ion mass spectrometer (RIMS) experiment onboard the Dynamics Explorer 1 (DE 1) satellite was designed to perform energy and mass-per-charge analysis on low-energy ions (less than 50 eV) with mass/charge ratios ranging from 1 to 40 amu/Z. The DE 1 satellite, carrying the RIMS experiment, was launched into an elliptical polar orbit on August 3, 1981. The approximately 7.5 hour orbit has perigee of 675 km altitude and apogee of 24,875 km altitude. this document and those that following in this series, contains summary RIMS data spectrograms for each orbit for which RIMS data are available. The RIMS instrument began returning science data on day 280 of 1981 and continued to return usable data until the end of the DE mission in March 1991. It should be noted that studies of the RIMS data set should be conducted only with a thorough awareness of the material described in the introduction section presented here, or in collaboration with a scientist familiar with RIMS data analysis.

  2. Dynamics Explorer 1, retarding ion mass spectrometer summary spectrograms-82/230 to 82/265 spin-time spectrograms for H(+), He(+), O(+), N(+), O(++), M/Z = 2, and molecular ions

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The retarding ion mass spectrometer (RIMS) experiment onboard the Dynamics Explorer 1 (DE 1) satellite was designed to perform energy and mass-per-charge analysis on low-energy ions (less than 50 eV) with mass/charge ratios ranging from 1 to 40 amu/Z. the DE 1 satellite, carrying the RIMS experiment, was launched into an elliptical polar orbit on August 3, 1981. The approximately 7.5 hour orbit has perigee of 675 km altitude and apogee of 24,875 km altitude. This document and those that follow in this series, contain summary RIMS data spectrograms for each orbit for which RIMS data are available. The RIMS instrument began returning science data on day 280 of 1981 and continued to return usable data until the end of the DE mission in March 1991. It should be noted that studies of the RIMS data set should be conducted only with a thorough awareness of the material described in the introduction section presented here, or in collaboration with a scientist familiar with RIMS data analysis.

  3. Dynamics Explorer 1, retarding ion mass spectrometer summary spectrograms: 82/001 to 82/109 spin-time spectrograms for H(+), He(+), O(+), N(+), O(++), M/Z=2, and molecular ions

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Retarding Ion Mass Spectrometer (RIMS) experiment onboard the Dynamics Explorer 1 (DE 1) satellite was designed to perform energy and mass-per-change analysis on low-energy ions (less than 50 eV) with mass/charge ratios ranging from 1 to 40 amu/Z. The DE 1 satellite, carrying the RIMS experiment, was launched into an elliptical polar orbit on August 3, 1981. The approximate 7.5 hour orbit has perigee of 675 km altitude and apogee of 24,875 km altitude. This document, and those that follow in this series, contains summary RIMS data spectrograms for each orbit for which RIMS data are available. The RIMS instrument began returning science data on day 280 of 1981 and continued to return usable data until the end of the DE mission in March 1991. It should be noted that studies of the RIMS data set should be conducted only with a thorough awareness of the material described in the introduction section presented here, or in collaboration with a scientist familiar with RIMS data analysis.

  4. Dynamics Explorer 1, retarding ion mass spectrometer summary spectrograms: 82/001 to 82/109 spin-time spectrograms for H(+), He(+), O(+), N(+), O(++), M/Z=2, and molecular ions

    SciTech Connect

    Not Available

    1994-10-01

    The Retarding Ion Mass Spectrometer (RIMS) experiment onboard the Dynamics Explorer 1 (DE 1) satellite was designed to perform energy and mass-per-charge analysis on low-energy ions (less than 50 eV) with mass/charge ratios ranging from 1 to 40 amu/Z. The DE 1 satellite, carrying the RIMS experiment, was launched into an elliptical polar orbit on August 3, 1981. The approximate 7.5 hour orbit has perigee of 675 km altitude and apogee of 24,875 km altitude. This document, and those that follow in this series, contains summary RIMS data spectrograms for each orbit for which RIMS data are available. The RIMS instrument began returning science data on day 280 of 1981 and continued to return usable data until the end of the DE mission in March 1991. It should be noted that studies of the RIMS data set should be conducted only with a thorough awareness of the material described in the introduction section presented here, or in collaboration with a scientist familiar with RIMS data analysis.

  5. Apparatus and method for characterizing the transmission efficiency of a mass spectrometer

    NASA Technical Reports Server (NTRS)

    Srivasytava, Santash (Inventor)

    1990-01-01

    An electron/ion coincidence technique is employed to characterize the absolute mass dependent transmission efficiency of mass spectrometers. The technique is not dependent upon the partial pressure of the sample beam or the ionization cross sections of calibrant gases.

  6. Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX).

    PubMed

    Smith, Philip A; Lepage, Carmela R Jackson; Savage, Paul B; Bowerbank, Christopher R; Lee, Edgar D; Lukacs, Michael J

    2011-04-01

    The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H](+)) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H](+) ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d(15) provided evidence that [M+H](+) production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H](+) ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

  7. A novel ion trap that enables high duty cycle and wide m/z range on an orthogonal injection TOF mass spectrometer.

    PubMed

    Loboda, Alexander V; Chernushevich, Igor V

    2009-07-01

    Although TOF analyzers with orthogonal ion injection provide the whole spectrum without scanning, their duty cycle is low compared with scanning analyzers in single ion monitoring mode. Typical duty cycle is in the range of 5% to 30% depending on the instrument geometry and ion m/z value. We present here a novel trapping/releasing setup, which offers the duty cycle near 100% over a wide range. Operation in the mass range from m/z 120 to almost 2000 is demonstrated. Ions are trapped in a short linear ion trap at the end of the collision cell in an axial pseudopotential well created by additional rf ("AC") voltage applied to all four rods of the trap with the same amplitude and phase. The pseudopotential created by AC field is mass dependent, and by ramping down the AC voltage, ions can be released from the trap sequentially from high m/z to low, while all ions are gaining the same kinetic energy. Upon entering the TOF accelerator, ions with lower m/z catch up with heavier ions, and the AC ramp parameters can be selected to make all ions meet in the center of the TOF extraction region, resulting in sensitivity gains from 3 to 14 without loss of mass accuracy or resolution.

  8. Detection of atmospheric gaseous amines and amides by a high-resolution time-of-flight chemical ionization mass spectrometer with protonated ethanol reagent ions

    NASA Astrophysics Data System (ADS)

    Yao, Lei; Wang, Ming-Yi; Wang, Xin-Ke; Liu, Yi-Jun; Chen, Hang-Fei; Zheng, Jun; Nie, Wei; Ding, Ai-Jun; Geng, Fu-Hai; Wang, Dong-Fang; Chen, Jian-Min; Worsnop, Douglas R.; Wang, Lin

    2016-11-01

    Amines and amides are important atmospheric organic-nitrogen compounds but high time resolution, highly sensitive, and simultaneous ambient measurements of these species are rather sparse. Here, we present the development of a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) method, utilizing protonated ethanol as reagent ions to simultaneously detect atmospheric gaseous amines (C1 to C6) and amides (C1 to C6). This method possesses sensitivities of 5.6-19.4 Hz pptv-1 for amines and 3.8-38.0 Hz pptv-1 for amides under total reagent ion signals of ˜ 0.32 MHz. Meanwhile, the detection limits were 0.10-0.50 pptv for amines and 0.29-1.95 pptv for amides at 3σ of the background signal for a 1 min integration time. Controlled characterization in the laboratory indicates that relative humidity has significant influences on the detection of amines and amides, whereas the presence of organics has no obvious effects. Ambient measurements of amines and amides utilizing this method were conducted from 25 July to 25 August 2015 in urban Shanghai, China. While the concentrations of amines ranged from a few parts per trillion by volume to hundreds of parts per trillion by volume, concentrations of amides varied from tens of parts per trillion by volume to a few parts per billion by volume. Among the C1- to C6-amines, the C2-amines were the dominant species with concentrations up to 130 pptv. For amides, the C3-amides (up to 8.7 ppb) were the most abundant species. The diurnal and backward trajectory analysis profiles of amides suggest that in addition to the secondary formation of amides in the atmosphere, industrial emissions could be important sources of amides in urban Shanghai. During the campaign, photo-oxidation of amines and amides might be a main loss pathway for them in daytime, and wet deposition was also an important sink.

  9. Detection of formaldehyde emissions from an industrial zone in the Yangtze River Delta region of China using a proton transfer reaction ion-drift chemical ionization mass spectrometer

    NASA Astrophysics Data System (ADS)

    Ma, Yan; Diao, Yiwei; Zhang, Bingjie; Wang, Weiwei; Ren, Xinrong; Yang, Dongsen; Wang, Ming; Shi, Xiaowen; Zheng, Jun

    2016-12-01

    A proton transfer reaction ion-drift chemical ionization mass spectrometer (PTR-ID-CIMS) equipped with a hydronium (H3+O) ion source was developed and deployed near an industrial zone in the Yangtze River Delta (YRD) region of China in spring 2015 to investigate industry-related emissions of volatile organic compounds (VOCs). Air pollutants including formaldehyde (HCHO), aromatics, and other trace gases (O3 and CO) were simultaneously measured. Humidity effects on the sensitivity of the PTR-ID-CIMS for HCHO detection were investigated and quantified. The performances of the PTR-ID-CIMS were also validated by intercomparing with offline HCHO measurement technique using 2,4-dinitrophenylhydrazone (DNPH) cartridges and the results showed fairly good agreement (slope = 0.81, R2 = 0.80). The PTR-ID-CIMS detection limit of HCHO (10 s, three-duty-cycle averages) was determined to be 0.9-2.4 (RH = 1-81.5 %) parts per billion by volume (ppbv) based on 3 times the standard deviations of the background signals. During the field study, observed HCHO concentrations ranged between 1.8 and 12.8 ppbv with a campaign average of 4.1 ± 1.6 ppbv, which was comparable with previous HCHO observations in other similar locations of China. However, HCHO diurnal profiles showed few features of secondary formation. In addition, time series of both HCHO and aromatic VOCs indicated strong influence from local emissions. Using a multiple linear regression fit model, on average the observed HCHO can be attributed to secondary formation (13.8 %), background level (27.0 %), and industry-related emissions, i.e., combustion sources (43.2 %) and chemical productions (16.0 %). Moreover, within the plumes the industry-related emissions can account for up to 69.2 % of the observed HCHO. This work has provided direct evidence of strong primary emissions of HCHO from industry-related activities. These primary HCHO sources can potentially have a strong impact on local and regional air pollution formation

  10. Characteristics and performance of several mass spectrometer residual gas analyzers

    NASA Technical Reports Server (NTRS)

    Hultzman, W. W.

    1974-01-01

    The operation and properties of various mass-spectrometer residual gas analyzers for use in vacuum measurements were analyzed in terms of efficiencies of ion extraction, ion separation and transmission, and ion collection. Types of instruments studied were magnetic sector, omegatron, quadrupole, and monopole. Experimental results presented include absolute sensitivity to argon, relative sensitivity to 10 gases, and cracking patterns for these gases. It is shown that the properties are strongly dependent on instrument range, resolution, and the particular voltages, currents, or field intensities used to control the instrument.

  11. Thermal desorption mass spectrometer for mass metrology.

    PubMed

    Silvestri, Z; Azouigui, S; Bouhtiyya, S; Macé, S; Plimmer, M D; Pinot, P; Tayeb-Chandoul, F; Hannachi, R

    2014-04-01

    This article presents a device for the study of physisorbed elements on polished surfaces (diameter ⩽56 mm) of the kind used in mass metrology. The technique is based on mass spectrometry of molecules desorbed after heating under vacuum of the analyzed surface. We describe a first application of the device to study current and future mass standards in order to understand how their surface reactivity depends on storage conditions, cleaning processes, and polishing methods. Surface contamination analysis by thermal desorption mass spectrometry to examine the effect of cleaning on pure iridium is given as an example.

  12. A miniature mass spectrometer for hydrazine detection

    NASA Technical Reports Server (NTRS)

    Houseman, J.; Sinha, M. P.

    2003-01-01

    A Miniature Mass Spectrometer (MMS) with a focal plane (Mattauch-Herzog) geometry has been developed at the Jet Propulsion Laboratory. The MMS has the potential to meet the NASA requirements of 10 parts per billion sensitivity for Hydrazine detection, as well as the requirements for instant response, portability, and low maintenance.

  13. Miniature Mass Spectrometers on Space and Planetary Missions

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, William

    2008-01-01

    Space flight mass spectrometers contribute our understanding of the origin and evolution of our solar system and even of life itself. This fundamental role has motivated increasing interest in miniature mass spectrometry for planetary missions. Several remarkable new instruments are en route or under development to investigate the composition of planetary bodies such as Mars and comets. For instance, the Sample Analysis at Mars (SAM) suite on the 2009 Mars Science Laboratory (MSL) mission includes a quadrupole mass spectrometer with a sophisticated gas processing system as well as pyrolysis and chemical derivatization protocols for solid samples. Future missions will require even lighter, lower power, and yet more capable mass spectrometers, particularly to analyze samples in situ on planetary surfaces. We have been developing laser-based mass spectrometers for elemental and organic/molecular analysis of rock, ice, or fine particle samples. These typically use time-of-flight (TOF) mass analyzers, which are readily miniaturized and can detect both atomic species and complex organics that occur in a variety of planetary materials. For example, nonvolatile polycyclic aromatic hydrocarbons and kerogen-like macromolecular carbon are found in some carbonaceous meteorites, which derived from asteroid parent bodies. A single focused laser pulse is able to volatilize and ionize some of these compounds for direct TOF analysis. While this is possible without any sample preparation or contact, sensitivity and quantitative performance can improve significantly with some sample handling. As such we have also been examining robotic mechanisms and protocols to accompany space flight mass spectrometers. In addition, sensors in early development may significantly improve these capabilities, via use of techniques such as switchable polarity, ambient pressure, or resonant ionization; tandem mass spectrometry (TOF or ion trap); and chemical imaging.

  14. IDENTIFICATION OF MICROCYSTIN TOXINS FROM A STRAIN OF MICROCYSTIS AERUGINOSA BY LIQUID CHROMATOGRAPHY INTRODUCTION INTO A HYBRID LINEAR ION TRAP-FOURIER TRANSFORM ION CYCLOTRON RESONANCE MASS SPECTROMETER

    EPA Science Inventory

    The cyclic heptapeptide microcystin toxins produced by a strain of Microcystis aeruginosa that has not been investigated previously were separated by liquid chromatography and identified by high-accuracy m/z measurements of their [M + H]+ ions and the fragment i...

  15. Comparison of triple quadrupole, hybrid linear ion trap triple quadrupole, time-of-flight and LTQ-Orbitrap mass spectrometers in drug discovery phase metabolite screening and identification in vitro--amitriptyline and verapamil as model compounds.

    PubMed

    Rousu, Timo; Herttuainen, Jukka; Tolonen, Ari

    2010-04-15

    Liquid chromatography in combination with mass spectrometry (LC/MS) is a superior analytical technique for metabolite profiling and identification studies performed in drug discovery and development laboratories. In the early phase of drug discovery the analytical approach should be both time- and cost-effective, thus providing as much data as possible with only one visit to the laboratory, without the need for further experiments. Recent developments in mass spectrometers have created a situation where many different mass spectrometers are available for the task, each with their specific strengths and drawbacks. We compared the metabolite screening properties of four main types of mass spectrometers used in analytical laboratories, considering both the ability to detect the metabolites and provide structural information, as well as the issues related to time consumption in laboratory and thereafter in data processing. Human liver microsomal incubations with amitriptyline and verapamil were used as test samples, and early-phase 'one lab visit only' approaches were used with all instruments. In total, 28 amitriptyline and 69 verapamil metabolites were found and tentatively identified. Time-of-flight mass spectrometry (TOFMS) was the only approach detecting all of them, shown to be the most suitable instrument for elucidating as comprehensive metabolite profile as possible leading also to lowest overall time consumption together with the LTQ-Orbitrap approach. The latter however suffered from lower detection sensitivity and false negatives, and due to slow data acquisition rate required slower chromatography. Approaches with triple quadrupole mass spectrometry (QqQ) and hybrid linear ion trap triple quadrupole mass spectrometry (Q-Trap) provided the highest amount of fragment ion data for structural elucidation, but, in addition to being unable to produce very high-important accurate mass data, they suffered from many false negatives, and especially with the Qq

  16. Formation of (bn−1 + H2O) Ions by Collisional Activation of MALDI-formed Peptide [M + H]+ Ions in a QqTOF Mass Spectrometer*

    PubMed Central

    She, Yi-Min; Krokhin, Oleg; Spicer, Victor; Loboda, Alexandre; Garland, Gideon; Ens, Werner; Standing, Kenneth G.; Westmore, John B.

    2007-01-01

    Collisional activation of [M + H]+ parent ions from peptides of n amino acid residues may yield a rearrangement that involves loss of the C-terminal amino acid residue to produce (bn−1+H2O) daughters. We have studied this reaction by a retrospective examination of the m/z spectra of two collections of data. The first set comprised 398 peptides from coat protein digests of a number of plant viruses by various enzymes, where conditions in the tryptic digests were chosen so as to produce many missed cleavages. In this case a large effect was observed– 323 (bn−1+H2O) daughter ions (~81%), including 185 (~ 46%) “strong” decays with ratios (bn−1+H2O)/(bn−1)>1. The second set comprised 1200 peptides, all from tryptic digests, which were carried out under more stringent conditions, resulting in relatively few missed cleavages. Even here, 190 (bn−1+H2O) ions (~ 16 %) were observed, including 87 (> 7%) “strong” decays, so the effect is still appreciable. The results suggest that the tendency for (bn−1+H2O) ion formation is promoted by the protonated side chain of a non-C-terminal basic amino acid residue, in the order arginine ≫ lysine ≥ histidine, and that its (non-C-terminal) position is not critical. The results can be interpreted by a mechanism in which hydrogen bonding between the protonated side chain and the (n-1) carbonyl oxygen facilitates loss of the C-terminal amino acid residue to give a product ion having a carboxyl group at the new C-terminus. PMID:17418589

  17. High-efficiency electron ionizer for a mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Darrach, Murray R. (Inventor); Orient, Otto J. (Inventor)

    2001-01-01

    The present invention provides an improved electron ionizer for use in a quadrupole mass spectrometer. The improved electron ionizer includes a repeller plate that ejects sample atoms or molecules, an ionizer chamber, a cathode that emits an electron beam into the ionizer chamber, an exit opening for excess electrons to escape, at least one shim plate to collimate said electron beam, extraction apertures, and a plurality of lens elements for focusing the extracted ions onto entrance apertures.

  18. Interface for liquid chromatograph-mass spectrometer

    DOEpatents

    Andresen, B.D.; Fought, E.R.

    1989-09-19

    A moving belt interface is described for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer. 8 figs.

  19. Interface for liquid chromatograph-mass spectrometer

    DOEpatents

    Andresen, Brian D.; Fought, Eric R.

    1989-01-01

    A moving belt interface for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer.

  20. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Fuerstenau, Stephen D. (Inventor); Orient, Otto J. (Inventor); Yee, Karl Y. (Inventor); Rice, John T. (Inventor)

    2000-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter, or pole array, for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  1. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Fuerstenau, Stephen D. (Inventor); Orient, Otto J. (Inventor); Yee, Karl Y. (Inventor); Rice, John T. (Inventor)

    2001-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter, or pole array, for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  2. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael (Inventor); Orient, Otto (Inventor); Wiberg, Dean (Inventor); Brennen, Reid A. (Inventor)

    2001-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and aligrnent for use in a final quadrupole mass spectrometer device.

  3. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael (Inventor); Orient, Otto (Inventor); Wiberg, Dean (Inventor); Brennen, Reid A. (Inventor)

    2000-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  4. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael (Inventor); Orient, Otto (Inventor); Wiberg, Dean (Inventor); Brennen, Reid A. (Inventor)

    2001-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  5. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Fuerstenau, Stephen D. (Inventor); Orient, Otto J. (Inventor); Yee, Karl Y. (Inventor); Rice, John T. (Inventor)

    2002-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter, or pole array, for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  6. Evaluation of a novel approach for peptide sequencing: laser-induced acoustic desorption combined with P(OCH(3))(2)(+) chemical ionization and collision-activated dissociation in a Fourier transform ion cyclotron resonance mass spectrometer.

    PubMed

    Somuramasami, Jayalakshmi; Kenttämaa, Hilkka I

    2007-03-01

    A novel mass spectrometric method has been developed for obtaining sequence information on small peptides. The peptides are desorbed as intact neutral molecules into a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR) by means of laser-induced acoustic desorption (LIAD). Reactions of the neutral peptides with the dimethoxyphosphenium ion, P(OCH(3))(2)(+), occur predominantly by addition of the peptide to P(OCH(3))(2)(+) followed by the loss of two methanol molecules, thus yielding product ions with the composition (peptide + P - 2H)(+). Upon sustained off-resonance irradiation for collision-activated dissociation (SORI-CAD), the (peptide + P - 2H)(+) ions undergo successive losses of CO and NHCHR or H(2)O, CO, and NHCHR to yield sequence-related fragment ions in addition to the regular a(n)- and b(n)-type ions. Under the same conditions, SORI-CAD of the analogous protonated peptides predominantly yields the regular a(n)- and b(n)-type ions. The mechanisms of the reactions of peptides with P(OCH(3))(2)(+) and the dissociation of the (peptide + P - 2H)(+) ions were examined by using model peptides and molecular orbital calculations.

  7. Evaluation of a Novel Approach for Peptide Sequencing: Laser-induced Acoustic Desorption Combined with P(OCH3)2+ Chemical Ionization and Collision-activated Dissociation in a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

    PubMed Central

    Somuramasami, Jayalakshmi; Kenttämaa, Hilkka I.

    2007-01-01

    A novel mass spectrometric method has been developed for obtaining sequence information on small peptides. The peptides are desorbed as intact neutral molecules into a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR) by means of laser-induced acoustic desorption (LIAD). Reactions of the neutral peptides with the dimethoxyphosphenium ion, P(OCH3)2+, occur predominantly by addition of the peptide to P(OCH3)2+ followed by the loss of two methanol molecules, thus yielding product ions with the composition (peptide + P − 2H)+. Upon sustained off-resonance irradiation for collision-activated dissociation (SORI-CAD), the (peptide + P − 2H)+ ions undergo successive losses of CO and NH = CHR or H2O, CO, and NH = CHR to yield sequence-related fragment ions in addition to the regular an- and bn-type ions. Under the same conditions, SORI-CAD of the analogous protonated peptides predominantly yields the regular an- and bn-type ions. The mechanisms of the reactions of peptides with P(OCH3)2+ and the dissociation of the (peptide + P − 2H)+ ions were examined by using model peptides and molecular orbital calculations. PMID:17157527

  8. Evaluation of Small Mass Spectrometer Systems

    NASA Technical Reports Server (NTRS)

    Arkin, C. Richard; Griffin, Timothy P.; Ottens, Andrew K.; Diaz, Jorge A.; Follistein, Duke W.; Adams, Fredrick W.; Helms, William R.; Voska, N. (Technical Monitor)

    2002-01-01

    This work is aimed at understanding the aspects of designing a miniature mass spectrometer (MS) system. A multitude of commercial and government sectors, such as the military, environmental agencies and industrial manufacturers of semiconductors, refrigerants, and petroleum products, would find a small, portable, rugged and reliable MS system beneficial. Several types of small MS systems are evaluated and discussed, including linear quadrupole, quadrupole ion trap, time of flight and sector. The performance of each system in terms of accuracy, precision, limits of detection, response time, recovery time, scan rate, volume and weight is assessed. A performance scale is setup to rank each systems and an overall performance score is given to each system. All experiments involved the analysis of hydrogen, helium, oxygen and argon in a nitrogen background with the concentrations of the components of interest ranging from 0-5000 part-per-million (ppm). The relative accuracies of the systems vary from < 1% to approx. 40% with an average below 10%. Relative precisions varied from 1% to 20%, with an average below 5%. The detection limits had a large distribution, ranging from 0.2 to 170 ppm. The systems had a diverse response time ranging from 4 s to 210 s as did the recovery time with a 6 s to 210 s distribution. Most instruments had scan times near, 1 s, however one instrument exceeded 13 s. System weights varied from 9 to 52 kg and sizes from 15 x 10(exp 3)cu cm to 110 x 10(exp 3) cu cm.

  9. New perspectives in laser analytics: Resonance-enhanced multiphoton ionization in a Paul ion trap combined with a time-of-flight mass spectrometer

    NASA Astrophysics Data System (ADS)

    Bisling, Peter; Heger, Hans Jörg; Michaelis, Walfried; Weitkamp, Claus; Zobel, Harald

    1995-04-01

    A new laser analytical device has been developed that is based on resonance-enhanced multiphoton ionization in the very center of a radio-frequency quadrupole ion trap. Applications in speciation anlaysis of biological and enviromental samples and in materials science will all benefit from laser-optical selectivity in the resonance excitation process, combined with mass-spectropic sensivity which is further enhanced by the ion accumulation and storage capability.

  10. A Mass Spectrometer Simulator in Your Computer

    NASA Astrophysics Data System (ADS)

    Gagnon, Michel

    2012-12-01

    Introduced to study components of ionized gas, the mass spectrometer has evolved into a highly accurate device now used in many undergraduate and research laboratories. Unfortunately, despite their importance in the formation of future scientists, mass spectrometers remain beyond the financial reach of many high schools and colleges. As a result, it is not possible for instructors to take full advantage of this equipment. Therefore, to facilitate accessibility to this tool, we have developed a realistic computer-based simulator. Using this software, students are able to practice their ability to identify the components of the original gas, thereby gaining a better understanding of the underlying physical laws. The software is available as a free download.

  11. Capillary zone electrophoresis-mass spectrometer interface

    DOEpatents

    D'Silva, Arthur

    1996-08-06

    A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conducts is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer.

  12. Capillary zone electrophoresis-mass spectrometer interface

    DOEpatents

    D`Silva, A.

    1996-08-06

    A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conductors is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer. 1 fig.

  13. Pioneer Venus large probe neutral mass spectrometer

    NASA Technical Reports Server (NTRS)

    Hoffman, J.

    1982-01-01

    The deuterium hydrogen abundance ratio in the Venus atmosphere was measured while the inlets to the Pioneer Venus large probe mass spectrometer were coated with sulfuric acid from Venus' clouds. The ratio is (1.6 + or - 0.2) x 10 to the minus two power. It was found that the 100 fold enrichment of deuterium means that Venus outgassed at least 0.3% of a terrestrial ocean and possibly more.

  14. Expert overseer for mass spectrometer system

    DOEpatents

    Filby, Evan E.; Rankin, Richard A.

    1991-01-01

    An expert overseer for the operation and real-time management of a mass spectrometer and associated laboratory equipment. The overseer is a computer-based expert diagnostic system implemented on a computer separate from the dedicated computer used to control the mass spectrometer and produce the analysis results. An interface links the overseer to components of the mass spectrometer, components of the laboratory support system, and the dedicated control computer. Periodically, the overseer polls these devices and as well as itself. These data are fed into an expert portion of the system for real-time evaluation. A knowledge base used for the evaluation includes both heuristic rules and precise operation parameters. The overseer also compares current readings to a long-term database to detect any developing trends using a combination of statistical and heuristic rules to evaluate the results. The overseer has the capability to alert lab personnel whenever questionable readings or trends are observed and provide a background review of the problem and suggest root causes and potential solutions, or appropriate additional tests that could be performed. The overseer can change the sequence or frequency of the polling to respond to an observation in the current data.

  15. Mechanism of Formation of the Major Estradiol Product Ions Following Collisional Activation of the Molecular Anion in a Tandem Quadrupole Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Wooding, Kerry M.; Barkley, Robert M.; Hankin, Joseph A.; Johnson, Christopher A.; Bradford, Andrew P.; Santoro, Nanette; Murphy, Robert C.

    2013-10-01

    The importance of the mass spectral product ion structure is highlighted in quantitative assays, which typically use multiple reaction monitoring (MRM), and in the discovery of novel metabolites. Estradiol is an important sex steroid whose quantitation and metabolite identification using tandem mass spectrometry has been widely employed in numerous clinical studies. Negative electrospray ionization tandem mass spectrometry of estradiol (E2) results in several product ions, including the abundant m/z 183 and 169. Although m/z 183 is one of the most abundant product ions used in many quantitative assays, the structure of m/z 183 has not been rigorously examined. We suggest a structure for m/z 183 and a mechanism of formation consistent with collision induced dissociation (CID) of E2 and several stable isotopes ([D4]-E2, [13C6]-E2, and [D1]-E2). An additional product ion from E2, namely m/z 169, has also been examined. MS3 experiments indicated that both m/z 183 and m/z 169 originate from only E2 [M - H]- m/z 271. These ions, m/z 183 and m/z 169, were also present in the collision induced decomposition mass spectra of other prominent estrogens, estrone (E1) and estriol (E3), indicating that these two product ions could be used to elucidate the estrogenic origin of novel metabolites. We propose two fragmentation schemes to explain the CID data and suggest a structure of m/z 183 and m/z 169 consistent with several isotopic variants and high resolution mass spectrometric measurements.

  16. A Remote Laser Mass Spectrometer for Lunar Resource Assessment

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Williams, M. D.

    1992-01-01

    The use of lasers as a source of excitation for surface mass spectroscopy has been investigated for some time. Since the laser can be focused to a small spot with intensity, it can vaporize and accelerate atoms of material. Using this phenomenon with a time-of-flight mass spectrometer allows a surface elemental mass analysis of a small region with each laser pulse. While the technique has been well developed for Earth applications, space applications are less developed. NASA Langley recently began a research program to investigate the use of a laser to create ions from the lunar surface and to analyze the ions at an orbiting spacecraft. A multijoule, Q-switched Nd:YAG laser would be focused to a small spot on the lunar surface, creating a dense plasma. This plasma would eject high-energy ions, as well as neutrals, electrons, and photons. An experiment is being set up to determine the characteristics of such a laser mass spectrometer at long flight distances. This experiment will determine the character of a future flight instrument for lunar resource assessment.

  17. Design and operational characteristics of a cast steel mass spectrometer

    SciTech Connect

    Blantocas, Gene Q.; Ramos, Henry J.; Wada, Motoi

    2004-09-01

    A cast steel magnetic sector mass analyzer is developed for studies of hydrogen and helium ion beams generated by a gas discharge compact ion source. The optimum induced magnetic flux density of 3500 G made it possible to scan the whole spectrum of hydrogen and helium ion species. Analysis of beam characteristics shows that the mass spectrometer sensitivity, and resolving power are approximately inversely proportional. The resolution is enhanced at higher pressures and lower current discharges. In contrast, the instrument sensitivity increased at higher current discharges and decreased at higher pressures. Calculations of the ultimate resolving power with reference to analyzer dimensions yield a numerical value of 30. System anomaly in the form of spherical aberrations was also analyzed using the paraxial beam envelope equation. Beam divergence is most significant at high discharge conditions where angular spread reaches an upper limit of 8.6 deg.

  18. Seven Channel Multi-collector Isotope Ratio Mass Spectrometer

    SciTech Connect

    Anthony D. Appelhans

    2008-07-01

    A new magnetic sector mass spectrometer that utilizes seven full-sized discrete dynode electron multipliers operating simultaneously has been designed, constructed and is in preliminary testing. The instrument utilizes a newly developed ion dispersion lens that enables the mass dispersed individual isotope beams to be separated sufficiently (35 mm) to allow a full-sized discrete dynode pulse counting multiplier to be used for each beam. The ion dispersion lens is a two element electrostatic 90 degree sector device that causes the beam-to-beam dispersion to increase faster than the intra-beam dispersion. Each multiplier is contained in an isolated case with a deflector/condenser lens at the entrance. A 9-sample filament cartridge is mounted on a micro-manipulator two-axis stage that enables adjustment of the filament position with 10 micron resolution within the ion lens. Results of initial testing with actinides will be presented.

  19. Study of a micro chamber quadrupole mass spectrometer

    SciTech Connect

    Wang Jinchan; Zhang Xiaobing; Mao Fuming; Xiao Mei; Cui Yunkang; Engelsen, Daniel den; Lei Wei

    2008-03-15

    The design of a micro chamber quadrupole mass spectrometer (MCQMS) having a small total volume of only 20 cm{sup 3}, including Faraday cup ion detector and ion source, is described. This MCQMS can resist a vacuum baking temperature of 400-500 deg. C. The quadrupole elements with a hyperbolic surface are made of a ceramic material and coated with a thin metal layer. The quadrupole mass filter has a field radius of 3 mm and a length of 100 mm. Prototypes of this new MCQMS can detect a minimum partial pressure of 10{sup -8} Pa, have a peak width of {delta}M=1 at 10% peak height from mass number 1 to 60, and show an excellent long-term stability. The new MCQMS is intended to be used in residual gas analyses of electron devices during a mutual pumping and baking process.

  20. Influence of instrumental parameters on the kinetic energy of ions and plasma temperature for a hexapole collision/reaction-cell-based inductively coupled plasma quadrupole mass spectrometer.

    PubMed

    Favre, Georges; Brennetot, René; Chartier, Frédéric; Tortajada, Jeanine

    2009-02-01

    Inductively coupled plasma mass spectrometry (ICP-MS) is widely used in inorganic analytical chemistry for element and/or isotope ratio measurements. The presence of interferences, which is one of the main limitations of this method, has been addressed in recent years with the introduction of collision/reaction cell devices on ICP-MS apparatus. The study of ion-molecule reactions in the gas phase then became of great importance for the development of new analytical strategies. Knowing the kinetic energy and the electronic states of the ions prior to their entrance into the cell, i.e., just before they react, thereby constitutes crucial information for the interpretation of the observed reactivities. Such studies on an ICP-MS commonly used for routine analyses require the determination of the influence of different instrumental parameters on the energy of the ions and on the plasma temperature from where ions are sampled. The kinetic energy of ions prior to their entrance into the cell has been connected to the voltage applied to the hexapole according to a linear relationship determined from measurements of ion energy losses due to collisions with neutral gas molecules. The effects of the plasma forward power, sampling depth, and the addition of a torch shield to the ICP source were then examined. A decrease of the plasma potential due to the torch shielding, already mentioned in the literature, has been quantified in this study at about 3 V.

  1. The Solar Wind Ion Composition Spectrometer

    NASA Technical Reports Server (NTRS)

    Gloeckler, G.; Geiss, J.; Balsiger, H.; Bedini, P.; Cain, J. C.; Fisher, J.; Fisk, L. A.; Galvin, A. B.; Gliem, F.; Hamilton, D. C.

    1992-01-01

    The Solar Wind Ion Composition Spectrometer (SWICS) on Ulysses is designed to determine uniquely the elemental and ionic-charge composition, and the temperatures and mean speeds of all major solar-wind ions, from H through Fe, at solar wind speeds ranging from 175 km/s (protons) to 1280 km/s (Fe(8+)). The instrument, which covers an energy per charge range from 0.16 to 59.6 keV/e in about 13 min, combines an electrostatic analyzer with postacceleration, followed by a time-of-flight and energy measurement. The measurements made by SWICS will have an impact on many areas of solar and heliospheric physics, in particular providing essential and unique information on: (1) conditions and processes in the region of the corona where the solar wind is accelerated; (2) the location of the source regions of the solar wind in the corona; (3) coronal heating processes; (4) the extent and causes of variations in the composition of the solar atmosphere; (5) plasma processes in the solar wind; (6) the acceleration of energetic particles in the solar wind; (7) the thermalization and acceleration of interstellar ions in the solar wind, and their composition; and (8) the composition, charge states, and behavior of the plasma in various regions of the Jovian magnetosphere.

  2. Miniature mass spectrometer systems based on a microengineered quadrupole filter.

    PubMed

    Malcolm, Andrew; Wright, Steven; Syms, Richard R A; Dash, Neil; Schwab, Marc-André; Finlay, Alan

    2010-03-01

    Two miniature mass spectrometer systems based on a microengineered quadrupole mass filter have been developed. One of the instruments has a footprint of 27 cm x 20 cm and is intended for laboratory use when space is at a premium. The other is portable and intended for use in the field. It is battery powered, weighs 14.9 kg, and is housed in a rugged case. This is the first example of a portable mass spectrometer incorporating an analyzer fabricated using microelectromechanical systems (MEMS) techniques. The starting material for construction of the filters is a bonded silicon on insulator substrate, which is selectively etched using batch processing techniques to form coupling optics and springs that accurately hold 0.5 mm diameter stainless steel rods in the required geometry. Assembled filters measure 35 mm x 6 mm x 1.5 mm and are mounted, together with an ion source and channeltron detector, in small, interchangeable cartridges, which plug into a 220 cm(3) vacuum chamber. Recovery from accidental contamination or when servicing is required can be achieved within 5-10 min, as the cartridge is easily exchanged with a spare. A potential application to environmental monitoring has been investigated. The headspace above water spiked with dibutyl mercaptan was sampled with a solid phase microextraction (SPME) fiber, which was then injected directly into the vacuum chamber of the mass spectrometer. Using this method, the limit of detection was found to be approximately 5 ppm for a 15 s sampling period.

  3. A tandem time-of-flight spectrometer for negative-ion/positive-ion coincidence measurements with soft x-ray excitation

    NASA Astrophysics Data System (ADS)

    Strâhlman, Christian; Sankari, Rami; Kivimäki, Antti; Richter, Robert; Coreno, Marcello; Nyholm, Ralf

    2016-01-01

    We present a newly constructed spectrometer for negative-ion/positive-ion coincidence spectroscopy of gaseous samples. The instrument consists of two time-of-flight ion spectrometers and a magnetic momentum filter for deflection of electrons. The instrument can measure double and triple coincidences between mass-resolved negative and positive ions with high detection efficiency. First results include identification of several negative-ion/positive-ion coincidence channels following inner-shell photoexcitation of sulfur hexafluoride (SF6).

  4. Evaluation of signal and noise and identification of a suitable target function in the tuning of an ESI ion trap mass spectrometer by multivariate pattern recognition tools.

    PubMed

    Marengo, Emilio; Robotti, Elisa; Gosetti, Fabio; Zerbinati, Orfeo; Gennaro, Maria Carla

    2009-10-01

    When mass spectrometry is not combined to separation techniques, the evaluation of signal and noise in a complex mass spectrum is not trivial. The tuning of the spectrometer based only on the increase of the signal of a selected number of m/z values does not ensure the achievement of the best experimental conditions: signal could improve and noise could increase as well. The scope of this work is the development of a function separating signal and noise (for evaluating the S/N) from complex mass spectra for potential use as target function for the automatic tuning of the instrument. Two different methods were applied: the first is based on the separation of a pool of m/z values attributable to the signal from the m/z values due to the noise, while the second is based on the application of principal component analysis to separate the signal (present in the significant components) from the noise (present in the residuals). The comparison of the two methods was carried out by the evaluation of the stability of the signal and the target functions obtained, and the evaluation of the variation of the target functions as a function of concentration.

  5. A high-resolution time-of-flight chemical ionization mass spectrometer utilizing hydronium ions (H3O+ ToF-CIMS) for measurements of volatile organic compounds in the atmosphere

    NASA Astrophysics Data System (ADS)

    Yuan, Bin; Koss, Abigail; Warneke, Carsten; Gilman, Jessica B.; Lerner, Brian M.; Stark, Harald; de Gouw, Joost A.

    2016-07-01

    Proton transfer reactions between hydronium ions (H3O+) and volatile organic compounds (VOCs) provide a fast and highly sensitive technique for VOC measurements, leading to extensive use of proton-transfer-reaction mass spectrometry (PTR-MS) in atmospheric research. Based on the same ionization approach, we describe the development of a high-resolution time-of-flight chemical ionization mass spectrometer (ToF-CIMS) utilizing H3O+ as the reagent ion. The new H3O+ ToF-CIMS has sensitivities of 100-1000 cps ppb-1 (ion counts per second per part-per-billion mixing ratio of VOC) and detection limits of 20-600 ppt at 3σ for a 1 s integration time for simultaneous measurements of many VOC species of atmospheric relevance. The ToF analyzer with mass resolution (m/Δm) of up to 6000 allows the separation of isobaric masses, as shown in previous studies using similar ToF-MS. While radio frequency (RF)-only quadrupole ion guides provide better overall ion transmission than ion lens system, low-mass cutoff of RF-only quadrupole causes H3O+ ions to be transmitted less efficiently than heavier masses, which leads to unusual humidity dependence of reagent ions and difficulty obtaining a humidity-independent parameter for normalization. The humidity dependence of the instrument was characterized for various VOC species and the behaviors for different species can be explained by compound-specific properties that affect the ion chemistry (e.g., proton affinity and dipole moment). The new H3O+ ToF-CIMS was successfully deployed on the NOAA WP-3D research aircraft for the SONGNEX campaign in spring of 2015. The measured mixing ratios of several aromatics from the H3O+ ToF-CIMS agreed within ±10 % with independent gas chromatography measurements from whole air samples. Initial results from the SONGNEX measurements demonstrate that the H3O+ ToF-CIMS data set will be valuable for the identification and characterization of emissions from various sources, investigation of secondary

  6. Electron Transfer Dissociation of All Ions at All Times, MSETD, in a Quadrupole Time-of-Flight (Q-ToF) Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Cramer, Christian N.; Brown, Jeffery M.; Tomczyk, Nick; Nielsen, Peter Kresten; Haselmann, Kim F.

    2017-02-01

    Data-independent mass spectral acquisition is particularly powerful when combined with ultra-performance liquid chromatography (LC) that provides excellent separation of most components present in a given sample. Data-independent analysis (DIA) consists of alternating full MS scans and scans with fragmentation of all ions within a selected m/z range, providing precursor masses and structure information, respectively. Fragmentation spectra are acquired either by sequential isolation and fragmentation of sliding m/z ranges or fragmenting all ions entering the MS instrument with no ion isolation, termed broadband DIA. Previously, broadband DIA has only been possible using collision induced dissociation (CID). Here, we report the use of electron transfer dissociation (ETD) as the fragmentation technique in broadband DIA instead of traditional collision induced dissociation (CID) during MSE. In this approach, which we refer to as MSETD, we implement the inherent benefits provided by ETD, such as discrimination of leucine and isoleucine, in a DIA setup. The combination of DIA analysis and ETD fragmentation with supplemental CID energy provides a powerful platform to obtain information on all precursors and their sequence from a single experiment.

  7. A compact E × B filter: A multi-collector cycloidal focusing mass spectrometer

    SciTech Connect

    Blase, Ryan C. Miller, Greg; Brockwell, Tim; Waite, J. Hunter; Westlake, Joseph; Ostrom, Nathaniel; Ostrom, Peggy H.

    2015-10-15

    A compact E × B mass spectrometer is presented. The mass spectrometer presented is termed a “perfect focus” mass spectrometer as the resolution of the device is independent of both the initial direction and energy of the ions (spatial and energy independent). The mass spectrometer is small in size (∼10.7 in.{sup 3}) and weight (∼2 kg), making it an attractive candidate for portability when using small, permanent magnets. A multi-collector Faraday cup design allows for the detection of multiple ion beams in discrete collectors simultaneously; providing the opportunity for isotope ratio monitoring. The mass resolution of the device is around 400 through narrow collector slits and the sensitivity of the device follows expected theoretical calculations of the ion current produced in the electron impact ion source. Example mass spectra obtained from the cycloidal focusing mass spectrometer are presented as well as information on mass discrimination based on instrumental parameters and isotope ratio monitoring of certain ion signals in separate Faraday cups.

  8. A compact E × B filter: A multi-collector cycloidal focusing mass spectrometer.

    PubMed

    Blase, Ryan C; Miller, Greg; Westlake, Joseph; Brockwell, Tim; Ostrom, Nathaniel; Ostrom, Peggy H; Waite, J Hunter

    2015-10-01

    A compact E × B mass spectrometer is presented. The mass spectrometer presented is termed a "perfect focus" mass spectrometer as the resolution of the device is independent of both the initial direction and energy of the ions (spatial and energy independent). The mass spectrometer is small in size (∼10.7 in.(3)) and weight (∼2 kg), making it an attractive candidate for portability when using small, permanent magnets. A multi-collector Faraday cup design allows for the detection of multiple ion beams in discrete collectors simultaneously; providing the opportunity for isotope ratio monitoring. The mass resolution of the device is around 400 through narrow collector slits and the sensitivity of the device follows expected theoretical calculations of the ion current produced in the electron impact ion source. Example mass spectra obtained from the cycloidal focusing mass spectrometer are presented as well as information on mass discrimination based on instrumental parameters and isotope ratio monitoring of certain ion signals in separate Faraday cups.

  9. Miniature Time-of-Flight Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Potember, Richard S.

    1999-01-01

    Major advances must occur to protect astronauts from prolonged periods in near-zero gravity and high radiation associated with extended space travel. The dangers of living in space must be thoroughly understood and methods developed to reverse those effects that cannot be avoided. Six of the seven research teams established by the National Space Biomedical Research Institute (NSBRI) are studying biomedical factors for prolonged space travel to deliver effective countermeasures. To develop effective countermeasures, each of these teams require identification of and quantitation of complex pharmacological, hormonal, and growth factor compounds (biomarkers) in humans and in experimental animals to develop an in-depth knowledge of the physiological changes associated with space travel. At present, identification of each biomarker requires a separate protocol. Many of these procedures are complicated and the identification of each biomarker requires a separate protocol and associated laboratory equipment. To carry all of this equipment and chemicals on a spacecraft would require a complex clinical laboratory; and it would occupy much of the astronauts time. What is needed is a small, efficient, broadband medical diagnostic instrument to rapidly identify important biomarkers for human space exploration. The Miniature Time-Of- Flight Mass Spectrometer Project in the Technology Development Team is developing a small, high resolution, time-of-flight mass spectrometer (TOFMS) to quantitatively measure biomarkers for human space exploration. Virtues of the JHU/APL TOFMS technologies reside in the promise for a small (less than one cubic ft), lightweight (less than 5 kg), low-power (less than 50 watts), rugged device that can be used continuously with advanced signal processing diagnostics. To date, the JHU/APL program has demonstrated mass capability from under 100 to beyond 10,000 atomic mass units (amu) in a very small, low power prototype for biological analysis. Further

  10. SIPT--An Ultrasensitive Mass Spectrometer for Rare Isotopes

    NASA Astrophysics Data System (ADS)

    Ringle, Ryan

    2014-09-01

    Over the last few decades, advances in radioactive beam facilities like the Coupled Cyclotron Facility at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU) have made short-lived, rare-isotope beams available for study in various science areas, and new facilities, like the Facility for Rare Isotope Beams (FRIB) under construction at MSU, will provide even more exotic rare isotopes. The determination of the masses of these rare isotopes is of utmost importance since it provides a direct measurement of the binding energy of the nucleons in the atomic nucleus. For this purpose we are currently developing a dedicated Single-Ion Penning Trap (SIPT) mass spectrometer at NSCL to handle the specific challenges posed by rare isotopes. These challenges, which include short half-lives and extremely low production rates, are dealt with by employing the narrowband FT-ICR detection method under cryogenic conditions. Used in concert with the 9.4-T time-of-flight mass spectrometer, the 7-T SIPT system will ensure that the LEBIT mass measurement program at MSU will make optimal use of the wide range of rare isotope beams provided by the future FRIB facility, addressing such topics as nuclear structure, nuclear astrophysics, and fundamental interactions. Over the last few decades, advances in radioactive beam facilities like the Coupled Cyclotron Facility at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU) have made short-lived, rare-isotope beams available for study in various science areas, and new facilities, like the Facility for Rare Isotope Beams (FRIB) under construction at MSU, will provide even more exotic rare isotopes. The determination of the masses of these rare isotopes is of utmost importance since it provides a direct measurement of the binding energy of the nucleons in the atomic nucleus. For this purpose we are currently developing a dedicated Single-Ion Penning Trap (SIPT) mass

  11. A sensitive method for digoxin determination using formate-adduct ion based on the effect of ionization enhancement in liquid chromatograph-mass spectrometer.

    PubMed

    Li, Xia; Wang, Yu; Zhou, Qingyuan; Yu, Yunqiu; Chen, Lihong; Zheng, Jie

    2015-01-26

    A sensitive and rapid method based on formate-adduct ion detection was developed and fully validated for digoxin determination in rat plasma. For LC/MS/MS detection with formate-adducts as precursor ions, transitions of m/z 825.5→779.9 for digoxin and m/z 809.5→763.4 for the internal standard (digitoxin) were monitored in negative mode. To investigate the impact of formic acid on the mass response and method sensitivity, a formic acid concentration range of 0-0.1% (0, 0.0005%, 0.002%, 0.01%, 0.1%, v/v) was evaluated. A concentration of 0.002% gave the highest sensitivity, which was 16- to 18-fold higher than deprotonated ions, and was designated as the contribution giving the strongest ionization enhancement and adduction. A number of parameters were then varied in order to optimize the method, and a limit of quantitation (LOQ) at 0.2 ng/mL was reached with an injection volume of 5 μL, a total run time of 3 min, and 0.1 mL of rat plasma. A calibration curve was plotted over the range 0.2-50 ng/mL (R(2)=0.9998), and the method was successfully applied to study pharmacokinetics in rat following a single oral administration of digoxin (0.05 mg/kg). Four additional steroid saponins (digitoxin, deslanoside, ginsenoside Rg1 and Rb1) were investigated to assess the impact of formic acid on the mass response of steroid saponins. Compounds with a conjugated lactonic ring in their structures such as digoxin, digitoxin and deslanoside tended to form stable formate-adduct ions more easily. The LC/MS/MS method developed here is therefore well suited for the quantification of steroid saponins that are difficult to deprotonate using other MS approaches.

  12. A computer controlled mass spectrometer system for investigating the decomposition of non-metallic materials under atmospheric conditions

    NASA Technical Reports Server (NTRS)

    Thompson, J. M.

    1985-01-01

    A PDP 11/23 quadrupole mass spectrometer system was coupled to a nondiscriminating gas inlet system permitting gases at atmospheric pressure to be admitted into a high vacuum chamber containing the ion source of the mass spectrometer without separation of the gaseous components. The resolution of related software problems has resulted in a convenient computer-mass spectrometer system capable of generating masses, relative intensities and related data on the gaseous products resulting from the atmospheric thermal decomposition of nonmetallic materials.

  13. Performance characteristics of an automated gas chromatograph-ion trap mass spectrometer system used for the 1995 Southern Oxidants Study field investigation in Nashville, Tennessee

    NASA Astrophysics Data System (ADS)

    Daughtrey, E. Hunter; Adams, Jeffrey R.; Oliver, Karen D.; Kronmiller, Keith G.; McClenny, William A.

    1998-09-01

    A trailer-deployed automated gas chromatograph-mass spectrometer (autoGC-MS) system capable of making continuous hourly measurements was used to determine volatile organic compounds (VOCs) in ambient air at New Hendersonville, Tennessee, and Research Triangle Park, North Carolina, in 1995. The system configuration, including the autoGC-MS, trailer and transfer line, siting, and sampling plan and schedule, is described. The autoGC-MS system employs a pair of matched sorbent traps to allow simultaneous sampling and desorption. Desorption is followed by Stirling engine cryofocusing and subsequent GC separation and mass spectral identification and quantification. Quality control measurements described include evaluating precision and accuracy of replicate analyses of independently supplied audit and round-robin canisters and determining the completeness of the data sets taken in Tennessee. Data quality objectives for precision (±10%) and accuracy (±20%) of 10- to 20-ppbv audit canisters and a completeness of >75% data capture were met. Quality assurance measures used in reviewing the data set include retention time stability, calibration checks, frequency distribution checks, and checks of the mass spectra. Special procedures and tests were used to minimize sorbent trap artifacts, to verify the quality of a standard prepared in our laboratory, and to prove the integrity of the insulated, heated transfer line. A rigorous determination of total system blank concentration levels using humidified scientific air spiked with ozone allowed estimation of method detection limits, ranging from 0.01 to 1.0 ppb C, for most of the 100 target compounds, which were a composite list of the target compounds for the Photochemical Assessment Monitoring Station network, those for Environmental Protection Agency method TO-14, and selected oxygenated VOCs.

  14. Low-Pressure, Field-Ionizing Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Hartley, Frank; Smith, Steven

    2009-01-01

    A small mass spectrometer utilizing a miniature field ionization source is now undergoing development. It is designed for use in a variety of applications in which there are requirements for a lightweight, low-power-consumption instrument that can analyze the masses of a wide variety of molecules and ions. The device can operate without need for a high-vacuum, carrier-gas feed radioactive ionizing source, or thermal ionizer. This mass spectrometer can operate either in the natural vacuum of outer space or on Earth at any ambient pressure below 50 torr (below about 6.7 kPa) - a partial vacuum that can easily be reached by use of a small sampling pump. This mass spectrometer also has a large dynamic range - from singly charged small gas ions to deoxyribonucleic acid (DNA) fragments larger than 104 atomic mass units - with sensitivity adequate for detecting some molecules and ions at relative abundances of less than one part per billion. This instrument (see figure) includes a field ionizer integrated with a rotating-field mass spectrometer (RFMS). The field ionizer effects ionization of a type characterized as "soft" in the art because it does not fragment molecules or initiate avalanche arcing. What makes the "soft" ionization mode possible is that the distance between the ionizing electrodes is less than mean free path for ions at the maximum anticipated operating pressure, so that the ionizer always operates on the non-breakdown side of the applicable Paschen curve (a standard plot of breakdown potential on the ordinate and pressure electrode separation on the abscissa). The field ionizer in this instrument is fabricated by micromachining a submicron-thick membrane out of an electrically nonconductive substrate, coating the membrane on both sides to form electrodes, then micromachining small holes through the electrodes and membrane. Because of the submicron electrode separation, even a potential of only 1 V applied between the electrodes gives rise to an electric

  15. A velocity map imaging spectrometer for electron?ion and ion?ion coincidence experiments with synchrotron radiation

    SciTech Connect

    Advanced Light Source; Kilcoyne, Arthur L; Rolles, D.; Pesic, Z.D.; Perri, M.; Bilodeau, R.C.; Ackerman, G.D.; Rude, B.S.; Kilcoyne, A.L.D.; Bozek, J.D.; Berrah, N.

    2007-04-27

    We have built a velocity imaging (VMI) spectrometer optimized for angle-resolved photoionization experiments with synchrotron radiation (SR) in the VUV and soft X-tay range. The spectrometer is equiped with four electrostatic lenses that focus the charged photoionization products onto a position-sensitive multi-hit delay-line anode. The use of two additional electrostatic lens elements as compared to the standard design of Eppink and Parker [T.J.B. Eppink and D.H. Parker, Rev. Sci. Instrum. 68 (1997) 3477]provides better focusing of an extended interaction region, which is crucial for most SR applications. Furthermore, the apparatus is equipped with a second micro-channel plate detector opposite to the VMI spectrometer, enabling electron-ion coincidence experiments and thereby mass-resolved ion spectroscopy independent of the time structure of the synchrotron radiation. First results for the photofragmentation of CO2 molecules are presented.

  16. Micro mass spectrometer on a chip.

    SciTech Connect

    Cruz, Dolores Y.; Blain, Matthew Glenn; Fleming, James Grant

    2005-11-01

    The design, simulation, fabrication, packaging, electrical characterization and testing analysis of a microfabricated a cylindrical ion trap ({mu}CIT) array is presented. Several versions of microfabricated cylindrical ion traps were designed and fabricated. The final design of the individual trap array element consisted of two end cap electrodes, one ring electrode, and a detector plate, fabricated in seven tungsten metal layers by molding tungsten around silicon dioxide (SiO{sub 2}) features. Each layer of tungsten is then polished back in damascene fashion. The SiO{sub 2} was removed using a standard release processes to realize a free-hung structure. Five different sized traps were fabricated with inner radii of 1, 1.5, 2, 5 and 10 {micro}m and heights ranging from 3-24 {micro}m. Simulations examined the effects of ion and neutral temperature, the pressure and nature of cooling gas, ion mass, trap voltage and frequency, space-charge, fabrication defects, and other parameters on the ability of micrometer-sized traps to store ions. The electrical characteristics of the ion trap arrays were determined. The capacitance was 2-500 pF for the various sized traps and arrays. The resistance was in the order of 1-2 {Omega}. The inductance of the arrays was calculated to be 10-1500 pH, depending on the trap and array sizes. The ion traps' field emission characteristics were assessed. It was determined that the traps could be operated up to 125 V while maintaining field emission currents below 1 x 10{sup -15} A. The testing focused on using the 5-{micro}m CITs to trap toluene (C{sub 7}H{sub 8}). Ion ejection from the traps was induced by termination of the RF voltage applied to the ring electrode and current measured on the collector electrode suggested trapping of ions in 1-10% of the traps. Improvements to the to the design of the traps were defined to minimize voltage drop to the substrate, thereby increasing trapping voltage applied to the ring electrode, and to allow

  17. Time-of-flight direct recoil ion scattering spectrometer

    DOEpatents

    Krauss, Alan R.; Gruen, Dieter M.; Lamich, George J.

    1994-01-01

    A time of flight direct recoil and ion scattering spectrometer beam line (10). The beam line (10) includes an ion source (12) which injects ions into pulse deflection regions (14) and (16) separated by a drift space (18). A final optics stage includes an ion lens and deflection plate assembly (22). The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions (14) and (16).

  18. Time-of-flight direct recoil ion scattering spectrometer

    DOEpatents

    Krauss, A.R.; Gruen, D.M.; Lamich, G.J.

    1994-09-13

    A time-of-flight direct recoil and ion scattering spectrometer beam line is disclosed. The beam line includes an ion source which injects ions into pulse deflection regions and separated by a drift space. A final optics stage includes an ion lens and deflection plate assembly. The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions. 23 figs.

  19. Subcellular-level resolution MALDI-MS imaging of maize leaf metabolites by MALDI-linear ion trap-Orbitrap mass spectrometer

    DOE PAGES

    Korte, Andrew R.; Yandeau-Nelson, Marna D.; Nikolau, Basil J.; ...

    2015-01-25

    A significant limiting factor in achieving high spatial resolution for matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) imaging is the size of the laser spot at the sample surface. We present modifications to the beam-delivery optics of a commercial MALDI-linear ion trap-Orbitrap instrument, incorporating an external Nd:YAG laser, beam-shaping optics, and an aspheric focusing lens, to reduce the minimum laser spot size from ~50 μm for the commercial configuration down to ~9 μm for the modified configuration. This improved system was applied for MALDI-MS imaging of cross sections of juvenile maize leaves at 5-μm spatial resolution using an oversampling method. Theremore » are a variety of different metabolites including amino acids, glycerolipids, and defense-related compounds were imaged at a spatial resolution well below the size of a single cell. Such images provide unprecedented insights into the metabolism associated with the different tissue types of the maize leaf, which is known to asymmetrically distribute the reactions of C4 photosynthesis among the mesophyll and bundle sheath cell types. The metabolite ion images correlate with the optical images that reveal the structures of the different tissues, and previously known and newly revealed asymmetric metabolic features are observed.« less

  20. Subcellular-level resolution MALDI-MS imaging of maize leaf metabolites by MALDI-linear ion trap-Orbitrap mass spectrometer

    SciTech Connect

    Korte, Andrew R.; Yandeau-Nelson, Marna D.; Nikolau, Basil J.; Lee, Young Jin

    2015-01-25

    A significant limiting factor in achieving high spatial resolution for matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) imaging is the size of the laser spot at the sample surface. We present modifications to the beam-delivery optics of a commercial MALDI-linear ion trap-Orbitrap instrument, incorporating an external Nd:YAG laser, beam-shaping optics, and an aspheric focusing lens, to reduce the minimum laser spot size from ~50 μm for the commercial configuration down to ~9 μm for the modified configuration. This improved system was applied for MALDI-MS imaging of cross sections of juvenile maize leaves at 5-μm spatial resolution using an oversampling method. There are a variety of different metabolites including amino acids, glycerolipids, and defense-related compounds were imaged at a spatial resolution well below the size of a single cell. Such images provide unprecedented insights into the metabolism associated with the different tissue types of the maize leaf, which is known to asymmetrically distribute the reactions of C4 photosynthesis among the mesophyll and bundle sheath cell types. The metabolite ion images correlate with the optical images that reveal the structures of the different tissues, and previously known and newly revealed asymmetric metabolic features are observed.

  1. Identification of oxidized organic atmospheric species during the Southern Oxidant and Aerosol Study (SOAS) using a novel Ion Mobility Time-of-Flight Chemical Ionization Mass Spectrometer (IMS-ToF-CIMS)

    NASA Astrophysics Data System (ADS)

    Krechmer, J.; Canagaratna, M.; Kimmel, J.; Junninen, H.; Knochenmuss, R.; Cubison, M.; Massoli, P.; Stark, H.; Jayne, J. T.; Surratt, J. D.; Jimenez, J. L.; Worsnop, D. R.

    2013-12-01

    We present results from the field deployment of a novel Ion Mobility Time-of-flight Chemical Ionization Mass Spectrometer (CI-IMS-TOF) during the Southern Oxidant and Aerosol Study (SOAS). IMS-TOF is a 2-dimensional analysis method, which separates gas-phase ions by mobility prior to determination of mass-to-charge ratio by mass spectrometry. Ion mobility is a unique physical property that is determined by the collisional cross section of an ion. Because mobility depends on size and shape, the IMS measurement is able to resolve isomers and isobaric compounds. Additionally, trends in IMS-TOF data space can be used to identify relationships between ions, such as common functionality or polymeric series. During SOAS we interfaced the IMS-TOF to a nitrate ion (NO3-) chemical ionization source that enables the selective ionization of highly oxidized gas phase species (those having a high O:C ratio) through clustering with the reagent ion. Highly oxidized products of terpenes and isoprene are important secondary organic aerosol precursors (SOA) that play an uncertain but important role in particle-phase chemistry. We present several case studies of atmospheric events during SOAS that exhibited elevated concentrations of sulfuric acid and/or organics. These events exhibited a rise in particle number and provide an opportunity to examine the role that organic species may have in local atmospheric new particle formation events. We also present the results from the field deployment and subsequent laboratory studies utilizing a Potential Aerosol Mass (PAM) flow reactor as the inlet for the CI-IMS-TOF. The reactor draws in ambient air and exposes it to high concentrations of the OH radical, created by photolysis O3 in the presence of water. The highly oxidized products are then sampled directly by the CI-IMS-TOF. We performed several experiments including placing pine and deciduous plants directly in front of the reactor opening and observed large increases in the number and

  2. Recent Advances in Water Analysis with Gas Chromatograph Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    MacAskill, John A.; Tsikata, Edem

    2014-01-01

    We report on progress made in developing a water sampling system for detection and analysis of volatile organic compounds in water with a gas chromatograph mass spectrometer (GCMS). Two approaches are described herein. The first approach uses a custom water pre-concentrator for performing trap and purge of VOCs from water. The second approach uses a custom micro-volume, split-splitless injector that is compatible with air and water. These water sampling systems will enable a single GC-based instrument to analyze air and water samples for VOC content. As reduced mass, volume, and power is crucial for long-duration, manned space-exploration, these water sampling systems will demonstrate the ability of a GCMS to monitor both air and water quality of the astronaut environment, thereby reducing the amount of required instrumentation for long duration habitation. Laboratory prototypes of these water sampling systems have been constructed and tested with a quadrupole ion trap mass spectrometer as well as a thermal conductivity detector. Presented herein are details of these water sampling system with preliminary test results.

  3. Implementing photodissociation in an Orbitrap mass spectrometer.

    PubMed

    Vasicek, Lisa A; Ledvina, Aaron R; Shaw, Jared; Griep-Raming, Jens; Westphall, Michael S; Coon, Joshua J; Brodbelt, Jennifer S

    2011-06-01

    We modified a dual pressure linear ion trap Orbitrap to permit infrared multiphoton dissociation (IRMPD) in the higher energy collisional dissociation (HCD) cell for high resolution analysis. A number of parameters, including the pressures of the C-trap and HCD cell, the radio frequency (rf) amplitude applied to the C-trap, and the HCD DC offset, were evaluated to optimize IRMPD efficiency and maintain a high signal-to-noise ratio. IRMPD was utilized for characterization of phosphopeptides, supercharged peptides, and N-terminal modified peptides, as well as for top-down protein analysis. The high resolution and high mass accuracy capabilities of the Orbitrap analyzer facilitated confident assignment of product ions arising from IRMPD.

  4. Implementing Photodissociation in an Orbitrap Mass Spectrometer

    PubMed Central

    Vasicek, Lisa A.; Ledvina, Aaron R.; Shaw, Jared; Griep-Raming, Jens; Westphall, Michael S.; Coon, Joshua J.; Brodbelt, Jennifer S.

    2011-01-01

    We modified a dual pressure linear ion trap Orbitrap to permit infrared multiphoton dissociation (IRMPD) in the higher energy collisional dissociation (HCD) cell for high resolution analysis. A number of parameters, including the pressures of the C-trap and HCD cell, the radio frequency (rf) amplitude applied to the C-trap, and the HCD DC offset, were evaluated to optimize IRMPD efficiency and maintain a high signal-to-noise ratio. IRMPD was utilized for characterization of phosphopeptides, supercharged peptides, and N-terminal modified peptides, as well as for top-down protein analysis. The high resolution and high mass accuracy capabilities of the Orbitrap analyzer facilitated confident assignment of product ions arising from IRMPD. PMID:21953052

  5. Multi-collector Isotope Ratio Mass Spectrometer -- Operational Performance Report

    SciTech Connect

    Appelhans, Anthony D; Olson, John E; Watrous, Matthew G; Ward, Michael B.; Dahl, David A.

    2010-12-01

    This report describes the operational testing of a new magnetic sector mass spectrometer that utilizes seven full-sized discrete dynode electron multipliers operating simultaneously. The instrument includes a newly developed ion dispersion lens that enables the mass dispersed individual isotope beams to be separated sufficiently to allow a full-sized discrete dynode pulse counting multiplier to be used to measure each isotope beam. The performance of the instrument was measured using SRM 996 (244Pu spike) at loadings of 2.4 and 12 fg on resin beads and with SRM 4350B Columbia River Sediment samples. The measured limit of detection (3s) for 240Pu was 3.4 attograms for SRM 996. The limit of quantitation (LOQ), defined as 10 s, was 11.2 attograms. The measured concentration of 239Pu in the CRS standard was 152 ± 6 fg/g.

  6. Driving a quadrupole mass spectrometer via an isolating stage

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Aalami, Dean (Inventor); Darrach, Murray (Inventor); Orient, Otto (Inventor)

    2002-01-01

    Driving a quadrupole mass spectrometer includes obtaining an air core transformer with a primary and a secondary, matching the secondary to the mass spectrometer, and driving the primary based on first and second voltage levels. Driving of the primary is via an isolating stage that minimizes low level drive signal coupling.

  7. Quadrupole mass spectrometer driver with higher signal levels

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Aalami, Dean (Inventor); Darrach, Murray (Inventor); Orient, Otto (Inventor)

    2003-01-01

    Driving a quadrapole mass spectrometer includes obtaining an air core transformer with a primary and a secondary, matching the secondary to the mass spectrometer, and driving the primary based on first and second voltage levels. Driving of the primary is via an isolating stage that minimizes low level drive signal coupling.

  8. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, Philippe

    1993-01-01

    A quadrupole mass spectrometer (QMS) system having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

  9. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, P.

    1993-04-20

    A quadrupole mass spectrometer (QMS) system is described having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

  10. Quantification of Biogenic and Anthropogenic Hydrocarbons using a Commercial Gas Chromatograph - Ion Trap Mass Spectrometer at a Ground Site near Fort McKay, AB

    NASA Astrophysics Data System (ADS)

    Tokarek, T. W.; Osthoff, H. D.

    2014-12-01

    The extraction of fossil fuels from the Alberta oil sands has been the focus of considerable attention due to its association with sizeable emissions of a variety of atmospheric pollutants, the magnitude and impacts of which are currently poorly constrained by observations. In order to more reliably estimate the magnitude and impact of these emissions, an intensive air quality measurement campaign, called "Fort McMurray Oil Sands Strategic Investigation of Local Sources" (FOSSILS), was conducted in the summer of 2013 as part of the Alberta-Canada joint oil sands monitoring program (JOSM) to identify and quantify emissions and their transformations from the Alberta oil sands. The challenge is that the region is surrounded by boreal forest, which provides a substantial background of biogenic hydrocarbons during summer. In this presentation, measurements of volatile organic compounds (VOCs) at the AMS13 ground site near Fort McKay, Alberta, from Aug 17 to Sept 6, 2013 using a commercial Griffin 450 gas chromatograph equipped with ion trap mass spectrometric detection and Tenax preconcentration are described. The combination of retention information and electron impact mass spectral data allowed unambiguous identification and quantification of the major biogenic monoterpenes, e.g., α and β-pinene, limonene, camphene, and 3Δ-carene, and of many anthropogenically derived hydrocarbons. Mixing ratios of biogenic hydrocarbons varied with time of day, temperature, and solar radiation, with maxima typically occurring at night, rationalized by nocturnal mixing heights and low mixing ratios of the nocturnal oxidants ozone (O3) and the nitrate radical (NO3). In contrast, mixing ratios of anthropogenic VOCs, e.g., benzene, toluene, ethyl benzene, and o-, p-, and m-xylene (BTEX), strongly depended on meteorological conditions, i.e., local wind direction. During episodes with high BTEX abundance, many additional high molecular weight hydrocarbons were observed which were not

  11. Open-split interface for mass spectrometers

    DOEpatents

    Diehl, John W.

    1991-01-01

    An open-split interface includes a connector body having four leg members projecting therefrom within a single plane, the first and third legs being coaxial and the second and fourth legs being coaxial. A tubular aperture extends through the first and third legs and a second tubular aperture extends through the second and fourth legs, connecting at a juncture within the center of the connector body. A fifth leg projects from the connector body and has a third tubular aperture extending therethrough to the juncture of the first and second tubular apertures. A capillary column extends from a gas chromatograph into the third leg with its end adjacent the juncture. A flow restrictor tube extends from a mass spectrometer through the first tubular aperture in the first and third legs and into the capillary columnm end, so as to project beyond the end of the third leg within the capillary column. An annular gap between the tube and column allows excess effluent to pass to the juncture. A pair of short capillary columns extend from separate detectors into the second tubular aperture in the second and fourth legs, and are oriented with their ends spaced slightly from the first capillary column end. A sweep flow tube is mounted in the fifth leg so as to supply a helium sweep flow to the juncture.

  12. Experimental Investigations of the Internal Energy of Molecules Evaporated via Laser-induced Acoustic Desorption into a Fourier-transform Ion Cyclotron Resonance Mass Spectrometer (LIAD/FT-ICR)

    PubMed Central

    Shea, Ryan C.; Petzold, Christopher J.; Liu, Ji-ang; Kenttämaa, Hilkka I.

    2008-01-01

    The internal energy of neutral gas-phase organic and biomolecules, evaporated by means of laser-induced acoustic desorption (LIAD) into a Fourier-transform ion cyclotron resonance mass spectrometer (FT-ICR), was investigated through several experimental approaches. The desorbed molecules were demonstrated not to undergo degradation during the desorption process by collecting LIAD-evaporated molecules and subjecting them to analysis by electrospray ionization/quadrupole ion trap mass spectrometry. Previously established gas-phase basicity (GB) values were remeasured for LIAD-evaporated organic molecules and biomolecules with the use of the bracketing method. No endothermic reactions were observed. The remeasured basicity values are in close agreement with the values reported in the literature. The amount of internal energy deposited during LIAD is concluded to be less than a few kcal/mol. Chemical ionization with a series of proton transfer reagents was employed to obtain a breakdown curve for a protonated dipeptide, val-pro, evaporated by LIAD. Comparison of this breakdown curve with a previously published analogous curve obtained by using substrate-assisted laser desorption (SALD) to evaporate the peptide suggests that the molecules evaporated via LIAD have less internal energy than those evaporated via SALD. PMID:17263513

  13. Synchronised Aerosol Mass Spectrometer Measurements across Europe

    NASA Astrophysics Data System (ADS)

    Nemitz, Eiko

    2010-05-01

    Up to twelve Aerodyne Aerosol Mass Spectrometers (AMSs) were operated simultaneously at rural and background stations (EMEP and EUSAAR sites) across Europe. Measurements took place during three intensive periods, in collaboration between the European EUCAARI IP and the EMEP monitoring activities under the UNECE Convention for Long-Range Transboundary Air Pollution (CLRTAP) during three contrasting months (May 2008, Sep/Oct 2008, Feb/Mar 2009). These measurements were conducted, analysed and quality controlled carefully using a unified protocol, providing the largest spatial database of aerosol chemical composition measured with a unified online technique to date, and a unique snapshots of the European non-refractory submicron aerosol climatology. As campaign averages over all active monitoring sites, organics represent 28 to 43%, sulphate 18 to 25%, ammonium 13 to 15% and nitrate 15 to 36% of the resolved aerosol mass, with the highest relative nitrate contribution during the Feb/Mar campaign. The measurements demonstrate that in NW Europe (e.g. Ireland, UK, The Netherlands, Germany, Switzerland) the regional submicron aerosol tends to be neutralised and here nitrates make a major contribution to the aerosol mass. By contrast, periods with low nitrate and acidic aerosol were observed at sites in S and E Europe (e.g. Greece, Finland), presumably due to a combination of larger SO2 point sources in Easter Europe, smaller local NH3 sources and, in the case of Greece, higher temperatures. While at the more marine and remote sites (Ireland, Scotland, Finland) nitrate concentrations were dominated by episodic transport phenomena, at continental sites (Switzerland, Germany, Hungary) nitrate followed a clear diurnal cycle, reflecting the thermodynamic behaviour of ammonium nitrate. The datasets clearly shows spatially co-ordinated, large-scale pollution episodes of organics, sulphate and nitrate, the latter being most pronounced during the Feb/Mar campaign. At selected

  14. Rotary turret and reusable specimen holder for mass spectrometer

    DOEpatents

    Banar, Joseph C.; Perrin, Richard E.; Ostrenga, Raymond A.

    1988-01-01

    A sample holder for use in a mass spectrometer is provided for heating a sample to discharge ions through an electrostatic field which focuses and accelerates the ions for analysis. Individual specimen holders form a plurality of filaments for heating the sample materials for ion emission. Mounting devices hold the plurality of filaments at regular spaced apart angles in a closed configuration adjacent the electrostatic field elements. A substantially solid ceramic turret is provided with a plurality of electrical contacts which engage the individual holder means for energizing the filaments and forming a corresponding plurality of radially facing, axially extending first conductive surfaces. A substantially solid stationary turret bearing member is mounted about the rotating turret with a plurality of radially biased second electrical conductive surfaces, mounted to electrically contact facing ones of the plurality of radially facing first conductive surfaces. The assembly provides a large thermal mass for thermal stability and large electrical contact areas for repeatable, stable power input for heating the sample materials. An improved sample holder is also provided having a ceramic body portion for removably engaging conductive wires. The conductive wires are compatible with a selected filament element and the sample material to be analyzed.

  15. SIEMENS ADVANCED QUANTRA FTICR MASS SPECTROMETER FOR ULTRA HIGH RESOLUTION AT LOW MASS

    SciTech Connect

    Spencer, W; Laura Tovo, L

    2008-07-08

    The Siemens Advanced Quantra Fourier Transform Ion Cyclotron Resonance (FTICR) mass spectrometer was evaluated as an alternative instrument to large double focusing mass spectrometers for gas analysis. High resolution mass spectrometers capable of resolving the common mass isomers of the hydrogen isotopes are used to provide data for accurate loading of reservoirs and to monitor separation of tritium, deuterium, and helium. Conventional double focusing magnetic sector instruments have a resolution that is limited to about 5000. The Siemens FTICR instrument achieves resolution beyond 400,000 and could possibly resolve the tritium ion from the helium-3 ion, which differ by the weight of an electron, 0.00549 amu. Working with Y-12 and LANL, SRNL requested Siemens to modify their commercial Quantra system for low mass analysis. To achieve the required performance, Siemens had to increase the available waveform operating frequency from 5 MHz to 40 MHz and completely redesign the control electronics and software. However, they were able to use the previous ion trap, magnet, passive pump, and piezo-electric pulsed inlet valve design. NNSA invested $1M in this project and acquired four systems, two for Y-12 and one each for SRNL and LANL. Siemens claimed a $10M investment in the Quantra systems. The new Siemens Advanced Quantra demonstrated phenomenal resolution in the low mass range. Resolution greater than 400,000 was achieved for mass 2. The new spectrometer had a useful working mass range to 500 Daltons. However, experiments found that a continuous single scan from low mass to high was not possible. Two useful working ranges were established covering masses 1 to 6 and masses 12 to 500 for our studies. A compromise performance condition enabled masses 1 to 45 to be surveyed. The instrument was found to have a dynamic range of about three orders of magnitude and quantitative analysis is expected to be limited to around 5 percent without using complex fitting algorithms

  16. A tandem mass spectrometer for collision-induced dissociation

    NASA Astrophysics Data System (ADS)

    1982-02-01

    A tandem mass spectrometer is described for studies of collision-induced dissociation. This instrument is especially suited for investigations on organic molecules, e.g., biochemical substances, for m/z values up to 1000. The first stage is formed by a conventional EI source and a sector magnet, and has a mass resolution of about 600. The first stage is provided with a collision gas cell at the site of the detector slit. In the second stage the fragment ions are post-accelerated in order to reduce the relative energy-spread and to increase the resolution and transmission. The fragment spectrum is analyzed by a second magnet (R = 750 mm, deflection angle = 15 deg) and simultaneously recorded. Quadrupoles are added in order to vary the dispersion and to aid focussing. The ratio between the highest and lowest masses in a simultaneously detected spectrum may vary from 4 : 1 to 1.06 : 1. The resolution can be as high as 600, and the transmission from the collision cell to the CEMA ranges from 60 to 100%; the detection sensitivity can be as high as 1 ion per 10 s.

  17. Ion mobility spectrometer for online monitoring of trace compounds1

    NASA Astrophysics Data System (ADS)

    Li, F.; Xie, Z.; Schmidt, H.; Sielemann, S.; Baumbach, J. I.

    2002-10-01

    The principle, character and developments of the instrumentation of ion mobility spectrometry are reviewed. The application of ion mobility spectrometers in monitoring chemical warfare agents, explosives, drugs, environmental hazardous compounds and industrial process control are discussed. Process applications with respect to miniaturization of the instrument are presented.

  18. Planar differential mobility spectrometer as a pre-filter for atmospheric pressure ionization mass spectrometry

    PubMed Central

    Schneider, Bradley B.; Covey, Thomas R.; Coy, Stephen L.; Krylov, Evgeny V.

    2010-01-01

    Ion filters based on planar DMS can be integrated with the inlet configuration of most mass spectrometers, and are able to enhance the quality of mass analysis and quantitative accuracy by reducing chemical noise, and by pre-separating ions of similar mass. This paper is the first in a series of three papers describing the optimization of DMS / MS instrumentation. In this paper the important physical parameters of a planar DMS-MS interface including analyzer geometry, analyzer coupling to a mass spectrometer, and transport gas flow control are considered. The goal is to optimize ion transmission and transport efficiency, provide optimal and adjustable resolution, and produce stable operation under conditions of high sample contamination. We discuss the principles of DMS separations and highlight the theoretical underpinnings. The main differences between planar and cylindrical geometries are presented, including a discussion of the advantages and disadvantages of RF ion focusing. In addition, we present a description of optimization of the frequency and amplitude of the DMS fields for resolution and ion transmission, and a discussion of the influence and importance of ion residence time in DMS. We have constructed a mass spectrometer interface for planar geometries that takes advantage of atmospheric pressure gas dynamic principles, rather than ion focusing, to minimize ion losses from diffusion in the analyzer and to maximize total ion transport into the mass spectrometer. A variety of experimental results has been obtained that illustrate the performance of this type of interface, including tests of resistance to high contamination levels, and the separation of stereoisomers. In a subsequent publication the control of the chemical interactions that drive the separation process of a DMS / MS system will be considered. In a third publication we describe novel electronics designed to provide the high voltages asymmetric waveform fields (SV) required for these

  19. Inficon Transpector MPH Mass Spectrometer Random Vibration Test Report

    NASA Technical Reports Server (NTRS)

    Santiago-Bond, Jo; Captain, Janine

    2015-01-01

    The purpose of this test report is to summarize results from the vibration testing of the INFICON Transpector MPH100M model Mass Spectrometer. It also identifies requirements satisfied, and procedures used in the test. As a payload of Resource Prospector, it is necessary to determine the survivability of the mass spectrometer to proto-qualification level random vibration. Changes in sensitivity of the mass spectrometer can be interpreted as a change in alignment of the instrument. The results of this test will be used to determine any necessary design changes as the team moves forward with flight design.

  20. Biotransformation and metabolic profile of buddleoside with human intestinal microflora by ultrahigh-performance liquid chromatography coupled to hybrid linear ion trap/orbitrap mass spectrometer.

    PubMed

    Tao, Jin-Hua; Duan, Jin-Ao; Jiang, Shu; Qian, Yi-Yun; Qian, Da-Wei

    2016-07-01

    Buddleoside (also known as linarin) as the major flavonoid in Chrysanthemum morifolium Ramat., has been reported to possess a wide range of pharmacological activities. The human intestinal microbiota might have an important impact on drug metabolism and ultimately on the drug oral bioavailability. However, the interaction of the buddleoside with human intestinal bacteria remains unknown. In this study, the conversion of buddleoside by different bacteria from human feces was firstly investigated. A reliable, sensitive and rapid analytical method, ultra performance liquid chromatography was established and successfully applied to investigate the metabolites and metabolic profile of buddleoside by human intestinal bacteria. Among the isolated bacteria, four strains including Escherichia sp. 4, Escherichia sp. 34, Enterococcus sp. 45 and Bacillus sp. 46 showed more powerful conversion capability. Based on the accurate mass data and the characteristic MS(n) product ions, the parent and six metabolites were detected and tentatively identified compared with blank samples. The metabolites were produced by four main metabolic pathways including deglycosylation, acetylation, methylation and hydroxylation. Buddleoside could be firstly converted to its aglycon acacetin (M2) by the majority of the isolated intestinal bacteria. Subsequently, M2 was further metabolize to its methylated (M3), acetylated (M4), hydroxylated (M5) and hydrogenated product (M6). However, acacetin-7-glucosid (M1) was obtained only from the minor bacterial samples like Bacillus sp. 46. To further explain the metabolism of buddleoside, the β-d-glucosidase and α-l-rhamnosidase activities of four strains were analyzed. Bacillus sp. 46 could only produce α-l-rhamnosidase, while the other three strains showed two kinds of enzyme activities. Furthermore, the activities of α-l-rhamnosidase and β-d-glucosidase reached the highest level at 12-18h and 10-12h, respectively. The metabolic routes and metabolites

  1. Mapping the stability diagram of a digital ion trap (DIT) mass spectrometer varying the duty cycle of the trapping rectangular waveform.

    PubMed

    Berton, Alberto; Traldi, Pietro; Ding, Li; Brancia, Francesco L

    2008-04-01

    In a digital ion trap the beta(r) and beta(z) boundary lines of the stability diagram are determined experimentally using an innovative approach. In the rectangular waveform-driven digital ion trap (DIT) manipulation of the waveform duty cycle allows introduction of a precisely defined DC quadrupole component into the main trapping field. Variation of the duty cycle can be controlled at software level without any hardware modification. The data generated use peptide ions, which produce stability diagrams in good agreement with the theoretical stability diagrams previously determined by simulation studies.

  2. Imaging thermal ion mass and velocity analyzer

    NASA Astrophysics Data System (ADS)

    Yau, A. W.; King, E. P.; Amerl, P.; Berg, K.; Enno, G.; Howarth, A.; Wevers, I.; White, A.

    2013-11-01

    The aim of an imaging thermal ion mass and velocity analyzer is to apply imaging techniques to measure in-situ the mass composition and detailed velocity phase space distributions of a thermal plasma population in a planetary ionosphere or magnetosphere and use the measured distributions to derive the bulk plasma parameters and to detect the possible presence of non-thermal distributions. A hemispherical electrostatic analyzer (HEA) with a planar entrance aperture can sample simultaneously incident ions or electrons over an extended energy range and the full 360° range of incident azimuth, and disperse them by their energy-per-charge while retaining their incident azimuth, thus providing a means to image the 2-dimensional (2D) ion or electron energy-per-charge and angular (azimuth) distribution. Therefore an ion mass and velocity analyzer consisting of a HEA embedded with an ion-mass spectrometer is capable of imaging the 2-D detailed ion velocity distribution—and measuring the 3D distribution on a spinning spacecraft if the planar entrance aperture is aligned along the spacecraft spin axis. For 3D velocity distribution measurements on a 3-axis stabilized spacecraft, an analyzer with electrostatic deflection capability will be required to deflect ions at arbitrary incident elevation angles into the planar entrance aperture for sampling. An imaging thermal ion mass and velocity analyzer is presented that combines a HEA, a time-of-flight ion mass spectrometer, and a pair of electrostatic deflectors, and is capable of sampling low-energy ions (˜1 to 100 eV/e) of all mass species (1 to > 40 AMU/e) from all incident directions on a non-spinning platform, at up to (10% energy resolution (ΔE/E) and ˜5° angular resolution. Using the HEA to measure the energy-percharge of each detected ion and the time-of-flight gate to measure the transit time of the ion inside the analyzer, this instrument can resolve all major ion species in the ionosphere including H+, He+ and O

  3. Targeted proteomic quantification on quadrupole-orbitrap mass spectrometer.

    PubMed

    Gallien, Sebastien; Duriez, Elodie; Crone, Catharina; Kellmann, Markus; Moehring, Thomas; Domon, Bruno

    2012-12-01

    There is an immediate need for improved methods to systematically and precisely quantify large sets of peptides in complex biological samples. To date protein quantification in biological samples has been routinely performed on triple quadrupole instruments operated in selected reaction monitoring mode (SRM), and two major challenges remain. Firstly, the number of peptides to be included in one survey experiment needs to be increased to routinely reach several hundreds, and secondly, the degree of selectivity should be improved so as to reliably discriminate the targeted analytes from background interferences. High resolution and accurate mass (HR/AM) analysis on the recently developed Q-Exactive mass spectrometer can potentially address these issues. This instrument presents a unique configuration: it is constituted of an orbitrap mass analyzer equipped with a quadrupole mass filter as the front-end for precursor ion mass selection. This configuration enables new quantitative methods based on HR/AM measurements, including targeted analysis in MS mode (single ion monitoring) and in MS/MS mode (parallel reaction monitoring). The ability of the quadrupole to select a restricted m/z range allows one to overcome the dynamic range limitations associated with trapping devices, and the MS/MS mode provides an additional stage of selectivity. When applied to targeted protein quantification in urine samples and benchmarked with the reference SRM technique, the quadrupole-orbitrap instrument exhibits similar or better performance in terms of selectivity, dynamic range, and sensitivity. This high performance is further enhanced by leveraging the multiplexing capability of the instrument to design novel acquisition methods and apply them to large targeted proteomic studies for the first time, as demonstrated on 770 tryptic yeast peptides analyzed in one 60-min experiment. The increased quality of quadrupole-orbitrap data has the potential to improve existing protein

  4. Analysis of secondary organic aerosol using a Micro-Orifice Volatilization Impactor (MOVI) coupled to an ion trap mass spectrometer with atmospheric pressure chemical ionization (APCI-IT/MS)

    NASA Astrophysics Data System (ADS)

    Brueggemann, M.; Vogel, A.; Hoffmann, T.

    2012-04-01

    We describe the development and characterization of a Micro-Orifice Volatilization Impactor (MOVI) which is coupled to an ion trap mass spectrometer with atmospheric pressure chemical ionization (APCI-IT/MS), and its application in laboratory and field measurements. The MOVI-APCI-IT/MS allows the quantification of organic acids and other oxidation products of volatile organic compounds (VOCs) in secondary organic aerosols (SOA) on a semi-continuous basis. Furthermore, the vapor pressure and saturation concentration of the particle components can be estimated. The MOVI was first described in 2010 by Yatavelli and Thornton (Yatavelli and Thornton, 2010). It is a single stage, multi-nozzle impactor with 100 nozzles, each having a diameter of 150 μm. At a flow-rate of 10 L·min-1 air is drawn through the MOVI and particles are collected on a deposition plate. The cut-point diameter (d50, diameter of 50% collection efficiency) is at 130 nm. A low pressure-drop of only 5.3% of atmospheric pressure behind the nozzles allows collecting not only low-volatile but even semi-volatile compounds, which are an important part of SOA. After collecting particles hydrocarbon-free synthetic air is led over the collection surface into the APCI-IT/MS and the collection surface is heated up to 120 ° C in less than 200 s, volatilizing the sampled SOA. The vaporized compounds are transferred into the ion source and subsequently analyzed by mass spectrometry. Due to the soft ionization at atmospheric pressure the obtained mass spectra show only low fragmentations and can easily be interpreted. In laboratory experiments the MOVI-APCI-IT/MS was used for the chemical analysis of SOA generated from α-pinene-ozonolysis in a smog chamber. The limit of detection was found at 7.3 ng for pinic acid. The vapor pressure log p0 and the saturation concentration C25* for pinic acid were calculated from the desorption temperature using the method presented by Faulhaber et al. (Faulhaber et al., 2009

  5. AUTOMATED DETERMINATION OF PRECURSOR ION, PRODUCT ION, AND NEUTRAL LOSS COMPOSITIONS AND DECONVOLUTION OF COMPOSITE MASS SPECTRA USING ION CORRELATION BASED ON EXACT MASSES AND RELATIVE ISOTOPIC ABUNDANCES

    EPA Science Inventory

    After a dispersive event, rapid determination of elemental compositions of ions in mass spectra is essential for tentatively identifying compounds. A Direct Analysis in Real Time (DART)® ion source interfaced to a JEOL AccuTOF® mass spectrometer provided exact masses accurate to ...

  6. Small mass spectrometer with extended measurement capabilities at high pressures. [for planetary atmosphere analysis

    NASA Technical Reports Server (NTRS)

    Von Zahn, U.; Mauersberger, K.

    1978-01-01

    For the in situ investigation of planetary atmospheres a small Mattauch-Herzog mass spectrometer has been developed. Its high-pressure performance has been improved by incorporating differential pumping between the ion source and the analyzing fields, shortening the path-length as well as increasing the extraction field in the ion source. In addition doubly ionized and dissociated ions are used for mass analysis. These measures make possible operation up to 0.01 millibars. Results of laboratory tests related to linearity, dynamic range, and mass resolution are presented, in particular for CO2.

  7. Mass spectrometer having a derivatized sample presentation apparatus

    DOEpatents

    Nelson, Randall W.

    2000-07-25

    A mass spectrometer having a derivatized sample presentation apparatus is provided. The sample presentation apparatus has a complex bound to the surface of the sample presentation apparatus. This complex includes a molecule which may chemically modify a biomolecule.

  8. Ion mobility spectrometer using frequency-domain separation

    DOEpatents

    Martin, Stephen J.; Butler, Michael A.; Frye, Gregory C.; Schubert, W. Kent

    1998-01-01

    An apparatus and method is provided for separating and analyzing chemical species in an ion mobility spectrometer using a frequency-domain technique wherein the ions generated from the chemical species are selectively transported through an ion flow channel having a moving electrical potential therein. The moving electrical potential allows the ions to be selected according to ion mobility, with certain of the ions being transported to an ion detector and other of the ions being effectively discriminated against. The apparatus and method have applications for sensitive chemical detection and analysis for monitoring of exhaust gases, hazardous waste sites, industrial processes, aerospace systems, non-proliferation, and treaty verification. The apparatus can be formed as a microelectromechanical device (i.e. a micromachine).

  9. Ion mobility spectrometer using frequency-domain separation

    DOEpatents

    Martin, S.J.; Butler, M.A.; Frye, G.C.; Schubert, W.K.

    1998-08-04

    An apparatus and method are provided for separating and analyzing chemical species in an ion mobility spectrometer using a frequency-domain technique wherein the ions generated from the chemical species are selectively transported through an ion flow channel having a moving electrical potential therein. The moving electrical potential allows the ions to be selected according to ion mobility, with certain of the ions being transported to an ion detector and other of the ions being effectively discriminated against. The apparatus and method have applications for sensitive chemical detection and analysis for monitoring of exhaust gases, hazardous waste sites, industrial processes, aerospace systems, non-proliferation, and treaty verification. The apparatus can be formed as a microelectromechanical device (i.e. a micromachine). 6 figs.

  10. Quantitative proteomics using the high resolution accurate mass capabilities of the quadrupole-orbitrap mass spectrometer.

    PubMed

    Gallien, Sebastien; Domon, Bruno

    2014-08-01

    High resolution/accurate mass hybrid mass spectrometers have considerably advanced shotgun proteomics and the recent introduction of fast sequencing capabilities has expanded its use for targeted approaches. More specifically, the quadrupole-orbitrap instrument has a unique configuration and its new features enable a wide range of experiments. An overview of the analytical capabilities of this instrument is presented, with a focus on its application to quantitative analyses. The high resolution, the trapping capability and the versatility of the instrument have allowed quantitative proteomic workflows to be redefined and new data acquisition schemes to be developed. The initial proteomic applications have shown an improvement of the analytical performance. However, as quantification relies on ion trapping, instead of ion beam, further refinement of the technique can be expected.

  11. Laser desorption time-of-flight mass spectrometer DNA analyzer. Final report

    SciTech Connect

    Chen, C.H.W.; Martin, S.A.

    1997-02-01

    The objective of this project is the development of a laser desorption time-of-flight mass spectrometer DNA analyzer which can be broadly used for biomedical research. Tasks include: pulsed ion extraction to improve resolution; two-component matrices to enhance ionization; and solid phase DNA purification.

  12. A remote laser-mass spectrometer for determination of elemental composition

    NASA Astrophysics Data System (ADS)

    De Young, R. J.; Situ, W.

    Determination of the elemental composition of lunar, asteroid, and planetary surfaces is a major concern for science and resource utilization of space. The science associated with the development of a satellite or lunar rover laser-mass spectrometer instrument is presented here. The instrument would include a pulsed laser with sufficient energy to create a plasma on a remote surface. Ions ejected from this plasma travel back to the spacecraft or rover, where they are analyzed by a time-of-flight mass spectrometer, giving the elemental and isotope composition. This concept is based on the LIMA-D instrument on board the former Soviet Union Phobos-88 spacecraft sent to Mars. A laser-mass spectrometer placed on a rover or satellite would substantially improve the data return over alternative techniques. The spatial resolution would be centimeters, and a complete mass spectrum could be achieved in one laser shot. An experiment is described that demonstrates these features. A 400 mj Nd:YAG laser is focused, to an intensity of 10(exp 11) w/sq cm, onto a Al, Ag, Cu, Ge, or lunar simulant target. A plasma forms from which ions are ejected. Some of these ions travel down an 18-m evacuated flight tube to a microchannel plate detector. Alternatively, the ions are captured by an ion trap where they are stored until pulsed into a 1-m time-of-flight mass spectrometer, giving the elemental composition of the remote surface. A television camera monitors the plasma plume shape, and a photodiode monitors the temporal plasma emission . With this system, ions of Al, Ag, Cu, Ge, and lunar simulant have been detected at 18 m. The mass spectrum from the ion trap and 1-m time-of-flight tube will be presented.

  13. A Remote Laser-mass Spectrometer for Determination of Elemental Composition

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Situ, W.

    1993-01-01

    Determination of the elemental composition of lunar, asteroid, and planetary surfaces is a major concern for science and resource utilization of space. The science associated with the development of a satellite or lunar rover laser-mass spectrometer instrument is presented here. The instrument would include a pulsed laser with sufficient energy to create a plasma on a remote surface. Ions ejected from this plasma travel back to the spacecraft or rover, where they are analyzed by a time-of-flight mass spectrometer, giving the elemental and isotope composition. This concept is based on the LIMA-D instrument on board the former Soviet Union Phobos-88 spacecraft sent to Mars. A laser-mass spectrometer placed on a rover or satellite would substantially improve the data return over alternative techniques. The spatial resolution would be centimeters, and a complete mass spectrum could be achieved in one laser shot. An experiment is described that demonstrates these features. A 400 mj Nd:YAG laser is focused, to an intensity of 10(exp 11) w/sq cm, onto a Al, Ag, Cu, Ge, or lunar simulant target. A plasma forms from which ions are ejected. Some of these ions travel down an 18-m evacuated flight tube to a microchannel plate detector. Alternatively, the ions are captured by an ion trap where they are stored until pulsed into a 1-m time-of-flight mass spectrometer, giving the elemental composition of the remote surface. A television camera monitors the plasma plume shape, and a photodiode monitors the temporal plasma emission . With this system, ions of Al, Ag, Cu, Ge, and lunar simulant have been detected at 18 m. The mass spectrum from the ion trap and 1-m time-of-flight tube will be presented.

  14. Effect of dissociation energy on ion formation and sensitivity of an analytical method for determination of chlorpyrifos in human blood, using gas chromatography-mass spectrometer (GC-MS in MS/MS)

    NASA Astrophysics Data System (ADS)

    Sinha, Sukesh Narayan; Pal, Ramavati; Dewan, Aruna; Mansuri, M. M.; Saiyed, H. N.

    2006-06-01

    A sensitive GC-MS method in MS/MS ion preparation was developed for quantitative estimation and qualitative determination of chlorpyrifos in human blood samples. This paper describes the combined effect of dissociation energy on ion formation of chlorpyrifos and sensitivity of this analytical method. Chlorpyrifos was extracted using methanol/hexane mixture from 0.2 ml human blood, deactivated with saturated acidic salt solution. The extract was then re-concentrated and analyzed by electron impact (EI) MS/MS gas chromatography-mass spectrometer. The MS/MS spectra of chlorpyrifos ion were recorded on different dissociation energy (30-100 V) to establish the structural confirmation and to demonstrate the effect of this energy on sensitivity, S/N ratio and detection limit for quantification of chlorpyrifos, which is first time reported. At different exciting amplitude (30-100 V), different behaviors of base peak, sensitivity, S/N ratio and detection limit of this method were observed for quantification of chlorpyrifos. The mass spectra recorded at dissociation energy <70 V, in between 70-80 V and >80 V correspond to the m/z 314 (100%), m/z 286 (100%) and m/z 258 (100%), respectively. The sensitivity, signal and detection limit of this method increased on 95 V at m/z 258. Therefore, m/z 258 was used for the quantification of chlorpyrifos. The detection limit for quantification was 0.1 ng/ml with S/N: 2 in human blood. The linear calibration curve with the correlation coefficient (r > 0.99) was obtained. The percentage recoveries from 95.33% to 107.67% were observed for chlorpyrifos from human blood. The blood samples were collected at different time intervals. The concentration of chlorpyrifos in poisoning case was 3300, 3000, 2200, 1000, 600, 300 ng/ml on day 1, 3, 6, 8, 10 and 12, respectively. On the 12th day of exposure of chlorpyrifos, 90.9% reduction in concentration was observed. On day 14th the chlorpyrifos was not detected in the blood of the same subject. Thus

  15. Plasma Composition in Jupiter's Magnetosphere: Initial Results from the Solar Wind Ion Composition Spectrometer.

    PubMed

    Geiss, J; Gloeckler, G; Balsiger, H; Fisk, L A; Galvin, A B; Gliem, F; Hamilton, D C; Ipavich, F M; Livi, S; Mall, U; Ogilvie, K W; von Steiger, R; Wilken, B

    1992-09-11

    The ion composition in the Jovian environment was investigated with the Solar Wind Ion Composition Spectrometer on board Ulysses. A hot tenuous plasma was observed throughout the outer and middle magnetosphere. In some regions two thermally different components were identified. Oxygen and sulfur ions with several different charge states, from the volcanic satellite lo, make the largest contribution to the mass density of the hot plasma, even at high latitude. Solar wind particles were observed in all regions investigated. Ions from Jupiter's ionosphere were abundant in the middle magnetosphere, particularly in the highlatitude region on the dusk side, which was traversed for the first time.

  16. Plasma composition in Jupiter's magnetosphere - Initial results from the Solar Wind Ion Composition Spectrometer

    NASA Technical Reports Server (NTRS)

    Geiss, J.; Gloeckler, G.; Balsiger, H.; Fisk, L. A.; Galvin, A. B.; Gliem, F.; Hamilton, D. C.; Ipavich, F. M.; Livi, S.; Mall, U.

    1992-01-01

    The ion composition in the Jovian environment was investigated with the Solar Wind Ion Composition Spectrometer on board Ulysses. A hot tenuous plasma was observed throughout the outer and middle magnetosphere. In some regions two thermally different components were identified. Oxygen and sulfur ions with several different charge states, from the volcanic satellite Io, make the largest contribution to the mass density of the hot plasma, even at high latitude. Solar wind particles were observed in all regions investigated. Ions from Jupiter's ionosphere were abundant in the middle magnetosphere, particularly in the high-latitude region on the dusk side, which was traversed for the first time.

  17. Rapid detection and identification of N-acetyl-L-cysteine thioethers using constant neutral loss and theoretical multiple reaction monitoring combined with enhanced product-ion scans on a linear ion trap mass spectrometer.

    PubMed

    Scholz, Karoline; Dekant, Wolfgang; Völkel, Wolfgang; Pähler, Axel

    2005-12-01

    A sensitive and specific liquid chromatography-mass spectrometry (LC-MS) method based on the combination of constant neutral loss scans (CNL) with product ion scans was developed on a linear ion trap. The method is applicable for the detection and identification of analytes with identical chemical substructures (such as conjugates of xenobiotics formed in biological systems) which give common CNLs. A specific CNL was observed for thioethers of N-acetyl-L-cysteine (mercapturic acids, MA) by LC-MS/MS. MS and HPLC parameters were optimized with 16 MAs available as reference compounds. All of these provided a CNL of 129 Da in the negative-ion mode. To assess sensitivity, a multiple reaction monitoring (MRM) mode with 251 theoretical transitions using the CNL of 129 Da combined with a product ion scan (IDA thMRM) was compared with CNL combined with a product ion scan (IDA CNL). An information-dependent acquisition (IDA) uses a survey scan such as MRM (multiple reaction monitoring) to generate "informations" and starting a second acquisition experiment such as a product ion scan using these "informations." Th-MRM means calculated transitions and not transitions generated from an available standard in the tuning mode. The product ion spectra provide additional information on the chemical structure of the unknown analytes. All MA standards were spiked in low concentrations to rat urines and were detected with both methods with LODs ranging from 60 pmol/mL to 1.63 nmol/mL with IDA thMRM. The expected product ion spectra were observed in urine. Application of this screening method to biological samples indicated the presence of a number of MAs in urine of unexposed rats, and resulted in the identification of 1,4-dihydroxynonene mercapturic acid as one of these MAs by negative and positive product ion spectra. These results show that the developed methods have a high potential to serve as both a prescreen to detect unknown MAs and to identify these analytes in complex matrix.

  18. Spacecraft Applications of Compact Optical and Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    Davinic, N. M.; Nagel, D. J.

    1995-01-01

    Optical spectrometers, and mass spectrometers to a lesser extent, have a long and rich history of use aboard spacecraft. Space mission applications include deep space science spacecraft, earth orbiting satellites, atmospheric probes, and surface landers, rovers, and penetrators. The large size of capable instruments limited their use to large, expensive spacecraft. Because of the novel application of micro-fabrication technologies, compact optical and mass spectrometers are now available. The new compact devices are especially attractive for spacecraft because of their small mass and volume, as well as their low power consumption. Dispersive optical multi-channel analyzers which cover the 0.4-1.1 micrometer wavelength are now commercially available in packages as small as 3 x 6 x 18 mm exclusive of drive and recording electronics. Mass spectrometers as small as 3 x 3 mm, again without electronics, are under development. A variety of compact optical and mass spectrometers are reviewed in this paper. A number of past space applications are described, along with some upcoming opportunities that are likely candidate missions to fly this new class of compact spectrometers.

  19. Development of an advanced spacecraft tandem mass spectrometer

    NASA Technical Reports Server (NTRS)

    Drew, Russell C.

    1992-01-01

    The purpose of this research was to apply current advanced technology in electronics and materials to the development of a miniaturized Tandem Mass Spectrometer that would have the potential for future development into a package suitable for spacecraft use. The mass spectrometer to be used as a basis for the tandem instrument would be a magnetic sector instrument, of Nier-Johnson configuration, as used on the Viking Mars Lander mission. This instrument configuration would then be matched with a suitable second stage MS to provide the benefits of tandem MS operation for rapid identification of unknown organic compounds. This tandem instrument is configured with a newly designed GC system to aid in separation of complex mixtures prior to MS analysis. A number of important results were achieved in the course of this project. Among them were the development of a miniaturized GC subsystem, with a unique desorber-injector, fully temperature feedback controlled oven with powered cooling for rapid reset to ambient conditions, a unique combination inlet system to the MS that provides for both membrane sampling and direct capillary column sample transfer, a compact and ruggedized alignment configuration for the MS, an improved ion source design for increased sensitivity, and a simple, rugged tandem MS configuration that is particularly adaptable to spacecraft use because of its low power and low vacuum pumping requirements. The potential applications of this research include use in manned spacecraft like the space station as a real-time detection and warning device for the presence of potentially harmful trace contaminants of the spacecraft atmosphere, use as an analytical device for evaluating samples collected on the Moon or a planetary surface, or even use in connection with monitoring potentially hazardous conditions that may exist in terrestrial locations such as launch pads, environmental test chambers or other sensitive areas. Commercial development of the technology

  20. New engineering design, instrument modeling, and data analysis techniques for spaceborne mass spectrometers

    NASA Astrophysics Data System (ADS)

    Gershman, Daniel J.

    This work describes technological innovations that can be used to improve upon space-borne mass spectrometers (MS), enabling breakthrough science and the development of the next-generation of sensors. Emphasis is placed on the two classes of MS with the strongest spaceflight heritage: quadrupole mass spectrometers (QMS) and time-of-flight mass spectrometers (TOF-MS). For the QMS, higher order auxiliary excitation techniques are modeled and implemented for the first time for both commercial and spaceflight-like sensors. These techniques, through modest modification of instrument electronics, are shown to significantly improve upon the maximum attainable mass resolution, sensitivity, ion rejection efficiency, and stability of measured mass spectra. For the TOF-MS, a complete analysis of instrument noise sources is conducted, and a mathematical framework for instrument measurements is developed. Such a framework results in an end-to-end forward modeling of instrument noise, dataset signal-to-noise estimation, and noise event removal algorithms. The developed noise processing techniques are applied to the Fast Imaging Plasma Spectrometer (FIPS) instrument on the MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) spacecraft to enable the first ever mapping of the spatial distribution of heavy ions at Mercury, the first in situ measurements of solar wind heavy ion non-thermal properties in the inner heliosphere, as well as the first in situ measurements made inside of Earth's orbit of ionized helium originating from interstellar space.

  1. Evaluation of multiple reaction monitoring cubed for the analysis of tachykinin related peptides in rat spinal cord using a hybrid triple quadrupole-linear ion trap mass spectrometer.

    PubMed

    Pailleux, Floriane; Beaudry, Francis

    2014-02-01

    Targeted peptide methods generally use HPLC-MS/MRM approaches. Although dependent on the instrumental resolution, interferences may occur while performing analysis of complex biological matrices. HPLC-MS/MRM(3) is a technique, which provides a significantly better selectivity, compared with HPLC-MS/MRM assay. HPLC-MS/MRM(3) allows the detection and quantitation by enriching standard MRM with secondary product ions that are generated within the linear ion trap. Substance P (SP) and neurokinin A (NKA) are tachykinin peptides playing a central role in pain transmission. The objective of this study was to verify whether HPLC-MS/MRM(3) could provide significant advantages over a more traditional HPLC-MS/MRM assay for the quantification of SP and NKA in rat spinal cord. The results suggest that reconstructed MRM(3) chromatograms display significant improvements with the nearly complete elimination of interfering peaks but the sensitivity (i.e. signal-to-noise ratio) was severely reduced. The precision (%CV) observed was between 3.5% and 24.1% using HPLC-MS/MRM and in the range of 4.3-13.1% with HPLC-MS/MRM(3), for SP and NKA. The observed accuracy was within 10% of the theoretical concentrations tested. HPLC-MS/MRM(3) may improve the assay sensitivity to detect difference between samples by reducing significantly the potential of interferences and therefore reduce instrumental errors.

  2. A constant-momentum/energy-selector time-of-flight mass spectrometer.

    PubMed

    Santacruz, C P; Håkansson, P; Barofsky, D F; Piyadasa, C K G

    2007-01-01

    A matrix assisted laser desorption/ionization time-of-flight mass spectrometer has been built with an ion source that can be operated in either constant-energy or constant-momentum acceleration modes. A decreasing electric field distribution in the ion-accelerating region makes it possible to direct ions onto a space-focal plane in either modes of operation. Ions produced in the constant-momentum mode have velocities and, thus, flight times that are linearly dependent on mass and kinetic energies that are inversely dependent on mass. The linear mass dispersion doubles mass resolving power of ions accelerated with space-focusing conditions in constant-momentum mode. The mass-dependent kinetic energy is exploited to disperse ions according to mass in a simple kinetic energy filter constructed from two closely spaced, oblique ion reflectors. Focusing velocity of ions of the same mass can substantially improve ion selection for subsequent post source decay or tandem time-of-flight analyses.

  3. Composition of Pickup Ions at Titan Observed by the Cassini Plasma Spectrometer

    NASA Technical Reports Server (NTRS)

    Hartle, R.; Sittler, E.; Burger, M.; Shappirio, M.; Johnson, R.; Smith, H.; Reisenfeld, D.; Szego, K.; Bertucci, C.; Neubauer, F.; Bolton, S.; Young, D.

    2006-01-01

    Pickup ions have been observed in Saturn's rotating magnetosphere near Titan by the Cassini Plasma Spectrometer (CAPS) instrument during the Cassini orbiter's recent flybys of the moon. A preliminary analysis of the CAPS Time of Flight (TOF) spectra of the pickup ions observed during the TA flyby indicated the presence of H(+), H2(+), N(+)/CH2(+), CH4(+), and N2(+). These ions slow down Saturn's magnetospheric plasma beyond Titan's ionosphere through mass loading. Because of its relatively high mass and high concentration, CH4(+) is the dominant mass loading ion. The other ions make negligible contributions to the mass loading process except for N2(+) just above the ionopause, where its concentration becomes important. With the exception of CH2(+), the pickup ion sources are the neutral exosphere constituents H, H2, N, CH4, and N2, where CH2 is a fragment of the parents CH4 and CH4(+). A more detailed analysis of CAPS TOF spectra and empirical cracking patterns is carried out to determine the relative concentrations of N(+) and CH2(+). Although, the 28 amu ion was identified as N2(+), consistent with the dominance of its neutral source, N2, just above the ionopause, the ionospheric ion HCNH(+) may also be present. The possible leakage of this and other ionospheric ions such as CH5(+) into the pickup ion /mass loading region is also examined by further analysis of the corresponding TOF spectra.

  4. Interference signals in "third-generation" BEBE sector field mass spectrometers

    NASA Astrophysics Data System (ADS)

    Schröder, Detlef; Schwarz, Helmut

    1995-08-01

    From the inception of analytical mass spectrometry numerous efforts have been undertaken to minimize artifacts in mass spectra. While double-focusing techniques brought about significant progress in that interference signals in ionsource mass spectra can now be excluded, for MS/MS studies several kinds of artifacts exist when only two sectors are used in MSn (n [greater-or-equal, slanted] 2) experiments. Tandem mass spectrometers having more than two sectors provide the possibility of mass-selecting parent ions under high resolution conditions and thus one might assume that artifact signals can be avoided in these machines. However, this is simply not true, and in this paper we describe possible sources of interference signals in a tandem mass spectrometer of BEBE configuration; similar considerations apply for other configurations of large-scale mass spectrometers as well. Artifact signals will be discussed which originate from limited parent-ion and/or daughter-ion resolution, from fragmentation processes occurring within the analyzers, and of interference signals which can be traced back to other sources.

  5. Ion source for high-precision mass spectrometry

    DOEpatents

    Todd, Peter J.; McKown, Henry S.; Smith, David H.

    1984-01-01

    The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit.

  6. Ion source for high-precision mass spectrometry

    DOEpatents

    Todd, P.J.; McKown, H.S.; Smith, D.H.

    1982-04-26

    The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit. 2 figures, 3 tables.

  7. Signal processing for ION mobility spectrometers

    NASA Technical Reports Server (NTRS)

    Taylor, S.; Hinton, M.; Turner, R.

    1995-01-01

    Signal processing techniques for systems based upon Ion Mobility Spectrometry will be discussed in the light of 10 years of experience in the design of real-time IMS. Among the topics to be covered are compensation techniques for variations in the number density of the gas - the use of an internal standard (a reference peak) or pressure and temperature sensors. Sources of noise and methods for noise reduction will be discussed together with resolution limitations and the ability of deconvolution techniques to improve resolving power. The use of neural networks (either by themselves or as a component part of a processing system) will be reviewed.

  8. A simple photoionization scheme for characterizing electron and ion spectrometers

    NASA Astrophysics Data System (ADS)

    Wituschek, A.; von Vangerow, J.; Grzesiak, J.; Stienkemeier, F.; Mudrich, M.

    2016-08-01

    We present a simple diode laser-based photoionization scheme for generating electrons and ions with well-defined spatial and energetic (≲2 eV) structures. This scheme can easily be implemented in ion or electron imaging spectrometers for the purpose of off-line characterization and calibration. The low laser power ˜1 mW needed from a passively stabilized diode laser and the low flux of potassium atoms in an effusive beam make our scheme a versatile source of ions and electrons for applications in research and education.

  9. A novel Laser Ion Mobility Spectrometer

    NASA Astrophysics Data System (ADS)

    Göbel, J.; Kessler, M.; Langmeier, A.

    2009-05-01

    IMS is a well know technology within the range of security based applications. Its main advantages lie in the simplicity of measurement, along with a fast and sensitive detection method. Contemporary technology often fails due to interference substances, in conjunction with saturation effects and a low dynamic detection range. High throughput facilities, such as airports, require the analysis of many samples at low detection limits within a very short timeframe. High detection reliability is a requirement for safe and secure operation. In our present work we developed a laser based ion-mobility-sensor which shows several advantages over known IMS sensor technology. The goal of our research was to increase the sensitivity compared to the range of 63Ni based instruments. This was achieved with an optimised geometric drift tube design and a pulsed UV laser system at an efficient intensity. In this intensity range multi-photon ionisation is possible, which leads to higher selectivity in the ion-formation process itself. After high speed capturing of detection samples, a custom designed pattern recognition software toolbox provides reliable auto-detection capability with a learning algorithm and a graphical user interface.

  10. EXTENDING THE USEFUL LIFE OF OLDER MASS SPECTROMETERS

    SciTech Connect

    Johnson, S.; Cordaro, J.; Holland, M.; Jones, V.

    2010-06-17

    Thermal ionization and gas mass spectrometers are widely used across the Department of Energy (DOE) Complex and contractor laboratories. These instruments support critical missions, where high reliability and low measurement uncertainty are essential. A growing number of these mass spectrometers are significantly older than their original design life. The reality is that manufacturers have declared many of the instrument models obsolete, with direct replacement parts and service no longer available. Some of these obsolete models do not have a next generation, commercially available replacement. Today's budget conscious economy demands for the use of creative funds management. Therefore, the ability to refurbish (or upgrade) these valuable analytical tools and extending their useful life is a cost effective option. The Savannah River Site (SRS) has the proven expertise to breathe new life into older mass spectrometers, at a significant cost savings compared to the purchase and installation of new instruments. A twenty-seven year old Finnigan MAT-261{trademark} Thermal Ionization Mass Spectrometer (TIMS), located at the SRS F/H Area Production Support Laboratory, has been successfully refurbished. Engineers from the Savannah River National Laboratory (SRNL) fabricated and installed the new electronics. These engineers also provide continued instrument maintenance services. With electronic component drawings being DOE Property, other DOE Complex laboratories have the option to extend the life of their aged Mass Spectrometers.

  11. Relativistic heavy ion fragmentation at HISS (Heavy Ion Spectrometer System)

    SciTech Connect

    Tull, C.E.

    1990-10-01

    An experiment was conducted at the Lawrence Berkeley Laboratory to measure projectile fragmentation of relativistic heavy ions. Charge identification was obtained by the use of a Cerenkov Hodoscope operating above the threshold for total internal reflection, while velocity measurement was performed by use of a second set of Cerenkov radiators operating at the threshold for total internal reflection. Charge and mass resolution for the system was {sigma}{sub Z} = 0.2 e and {sigma}{sub A} = 0.2 u. Measurements of the elemental and isotopic production cross sections for the fragmentation of {sup 40}Ar at 1.65{center dot}A GeV have been compared with an Abrasion-Ablation Model based on the evaporation computer code GEMINI. The model proves to be an accurate predictor of the cross sections for fragments between Chlorine and Boron. The measured cross section were reproduced using simple geometry with charge dispersions induced by zero-point vibrations of the giant dipole resonance for the prompt abrasion stage, and injecting an excitation energy spectrum based on a final state interaction with scaling factor E{sub fsi} = 38.8 MeV/c. Measurement of the longitudinal momentum distribution widths for projectile fragments are consistent with previous experiment and can be interpreted as reflecting the Fermi momentum distribution in the initial projectile nucleus. Measurement of the transverse momentum indicate an additional, unexplained dependence of the reduced momentum widths on fragment mass. This dependence has the same sign and similar slope to previously measured fragments of {sup 139}La, and to predictions based on phase-space constraints on the final state of the system.

  12. A hybrid liquid chromatography-mass spectrometry strategy in a forensic laboratory for opioid, cocaine and amphetamine classes in human urine using a hybrid linear ion trap-triple quadrupole mass spectrometer.

    PubMed

    Dowling, Geraldine; Regan, Liam; Tierney, Julie; Nangle, Michael

    2010-10-29

    A rapid method has been developed to analyse morphine, codeine, morphine-3-glucuronide, 6-monoacetylmorphine, cocaine, benzoylegonine, buprenorphine, dihydrocodeine, cocaethylene, 3,4-methylenedioxyamphetamine, ketamine, 3,4-methylenedioxymethamphetamine, pseudoephedrine, lignocaine, benzylpiperazine, methamphetamine, amphetamine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine and methadone in human urine. Urine samples were diluted with methanol:water (1:1, v/v) and sample aliquots were analysed by hybrid linear ion trap-triple quadrupole mass spectrometry with a runtime of 12.5 min. Multiple reaction monitoring (MRM) as survey scan and an enhanced product ion (EPI) scan as dependent scan were performed in an information-dependent acquisition (IDA) experiment. Finally, drug identification and confirmation was carried out by library search with a developed in-house MS/MS library based on EPI spectra at a collision energy spread of 35±15 in positive mode and MRM ratios. The method was validated in urine, according to the criteria defined in Commission Decision 2002/657/EC. At least two MRM transitions for each substance were monitored in addition to EPI spectra and deuterated analytes were used as internal standards for quantitation. The reporting level was 0.05 μg mL(-1) for the range of analytes tested. The regression coefficients (r(2)) for the calibration curves (0-4 μg mL(-1)) in the study were ≥0.98. The method proved to be simple and time efficient and was implemented as an analytical strategy for the illicit drug monitoring of opioids, cocaines and amphetamines in criminal samples from crime offenders, abusers or victims in the Republic of Ireland. To the best of our knowledge there are no hybrid LC-MS applications using MRM mode and product ion spectra in the linear ion trap mode for opioids, cocaines or amphetamines with validation data in urine.

  13. Mass spectrometer with electron source for reducing space charge effects in sample beam

    DOEpatents

    Houk, Robert S.; Praphairaksit, Narong

    2003-10-14

    A mass spectrometer includes an ion source which generates a beam including positive ions, a sampling interface which extracts a portion of the beam from the ion source to form a sample beam that travels along a path and has an excess of positive ions over at least part of the path, thereby causing space charge effects to occur in the sample beam due to the excess of positive ions in the sample beam, an electron source which adds electrons to the sample beam to reduce space charge repulsion between the positive ions in the sample beam, thereby reducing the space charge effects in the sample beam and producing a sample beam having reduced space charge effects, and a mass analyzer which analyzes the sample beam having reduced space charge effects.

  14. Sample introducing apparatus and sample modules for mass spectrometer

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1993-01-01

    An apparatus for introducing gaseous samples from a wide range of environmental matrices into a mass spectrometer for analysis of the samples is described. Several sample preparing modules including a real-time air monitoring module, a soil/liquid purge module, and a thermal desorption module are individually and rapidly attachable to the sample introducing apparatus for supplying gaseous samples to the mass spectrometer. The sample-introducing apparatus uses a capillary column for conveying the gaseous samples into the mass spectrometer and is provided with an open/split interface in communication with the capillary and a sample archiving port through which at least about 90 percent of the gaseous sample in a mixture with an inert gas that was introduced into the sample introducing apparatus is separated from a minor portion of the mixture entering the capillary discharged from the sample introducing apparatus.

  15. Sample introducing apparatus and sample modules for mass spectrometer

    DOEpatents

    Thompson, C.V.; Wise, M.B.

    1993-12-21

    An apparatus for introducing gaseous samples from a wide range of environmental matrices into a mass spectrometer for analysis of the samples is described. Several sample preparing modules including a real-time air monitoring module, a soil/liquid purge module, and a thermal desorption module are individually and rapidly attachable to the sample introducing apparatus for supplying gaseous samples to the mass spectrometer. The sample-introducing apparatus uses a capillary column for conveying the gaseous samples into the mass spectrometer and is provided with an open/split interface in communication with the capillary and a sample archiving port through which at least about 90 percent of the gaseous sample in a mixture with an inert gas that was introduced into the sample introducing apparatus is separated from a minor portion of the mixture entering the capillary discharged from the sample introducing apparatus. 5 figures.

  16. Ion mobility spectrometer, spectrometer analyte detection and identification verification system, and method

    DOEpatents

    Atkinson, David A.

    2002-01-01

    Methods and apparatus for ion mobility spectrometry and analyte detection and identification verification system are disclosed. The apparatus is configured to be used in an ion mobility spectrometer and includes a plurality of reactant reservoirs configured to contain a plurality of reactants which can be reacted with the sample to form adducts having varying ion mobilities. A carrier fluid, such as air or nitrogen, is used to carry the sample into the spectrometer. The plurality of reactants are configured to be selectively added to the carrier stream by use inlet and outlet manifolds in communication with the reagent reservoirs, the reservoirs being selectively isolatable by valves. The invention further includes a spectrometer having the reagent system described. In the method, a first reactant is used with the sample. Following a positive result, a second reactant is used to determine whether a predicted response occurs. The occurrence of the second predicted response tends to verify the existence of a component of interest within the sample. A third reactant can also be used to provide further verification of the existence of a component of interest. A library can be established of known responses of compounds of interest with various reactants and the results of a specific multi-reactant survey of a sample can be compared against the library to determine whether a component detected in the sample is likely to be a specific component of interest.

  17. A composition analyzer for microparticles using a spark ion source. [using time of flight spectrometers

    NASA Technical Reports Server (NTRS)

    Auer, S. O.; Berg, O. E.

    1975-01-01

    Iron microparticles were fired onto a capacitor-type microparticle detector which responded to an impact with a spark discharge. Ion currents were extracted from the spark and analyzed in a time-of-flight mass spectrometer. The mass spectra showed the element of both detector and particle materials. The total extracted ion currents was typically 10A within a period of 100ns, indicating very efficient vaporization of the particle and ionization of the vapor. Potential applications include research on cosmic dust, atmospheric aerosols and cloud droplets, particles ejected by rocket or jet engines, by machining processes, or by nuclear bomb explosions.

  18. Use of a Hand-Portable Gas Chromatograph-Toroidal Ion Trap Mass Spectrometer for Self-Chemical Ionization Identification of Degradation Products Related to O-ethyl S-(2-diisopropylaminoethyl) Methyl Phosphonothiolate (VX)

    DTIC Science & Technology

    2011-01-01

    M+H]+ in a triple quadrupole instrument [19], and methanol CI using an ion trap instrument [6] led to observation of a m/z 128 product ion. 4...products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is...is used with a quadrupole mass filter detector [1]. When EI is used in this man- ner, unimolecular decomposition is the norm, producing neutral and

  19. BerlinTrap: A new cryogenic 22-pole ion trap spectrometer

    NASA Astrophysics Data System (ADS)

    Günther, Alan; Nieto, Pablo; Müller, David; Sheldrick, Alexander; Gerlich, Dieter; Dopfer, Otto

    2017-02-01

    The design and first applications of a new tandem mass spectrometer (BerlinTrap) combining an electrospray ion source, a quadrupole mass spectrometer, a cryogenic 22-pole ion trap (4-300 K), and an orthogonal reflectron time-of-flight mass spectrometer are described. The trapped ions are cooled by helium buffer gas cooling. The formation and solvation shell structure of weakly-bound HenH3O+ complexes and the electronic photodissociation spectrum of the protonated amino acid tyrosine are used to calibrate the setup for cooling, tagging, and spectroscopic capabilities. A vibrational temperature below 20 K is inferred for protonated tyrosine. The electronic spectrum of isolated protonated lumichrome, the smallest protonated flavin, is recorded in the visible range and assigned to the most stable N5 isomer by comparison with quantum chemical calculations. These results demonstrate the suitability of the BerlinTrap apparatus for spectroscopy and reactivity studies of small and large (bio-)molecular ions and their clusters.

  20. Development of a dedicated isotope mass spectrometer for the noninvasive diagnostics of humans infected with Helicobacter Pylori

    NASA Astrophysics Data System (ADS)

    Blashenkov, N. M.; Sheshenya, E. S.; Solov'ev, S. M.; Gall', L. N.; Sachenko, V. M.; Zarutskii, I. V.; Gall', N. R.

    2013-06-01

    A dedicated isotope mass spectrometer for the noninvasive diagnostics of humans infected with Helicobacter Pylori using the isotope respiratory test is developed. A low-aberration mass analyzer is calculated, an input system that makes it possible to eliminate the memory effects is developed, and a small-size ion detector is constructed. The mass spectrometer is created, and the tests are performed. The measurement accuracy of the 13C/12C and 16O/18O isotope ratios are 1.7 and 2.2‰, respectively. Preliminary medical tests show that the spectrometer can be employed for the desired diagnostics.

  1. Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping

    NASA Astrophysics Data System (ADS)

    Dickel, Timo; Plaß, Wolfgang R.; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I.; Geissel, Hans; Scheidenberger, Christoph

    2017-03-01

    A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry.

  2. Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping.

    PubMed

    Dickel, Timo; Plaß, Wolfgang R; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I; Geissel, Hans; Scheidenberger, Christoph

    2017-03-15

    A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. Graphical Abstract ᅟ.

  3. A specialized isotope mass spectrometer for noninvasive diagnostics of Helicobacter pylori infection in human beings

    NASA Astrophysics Data System (ADS)

    Blashenkov, N. M.; Sheshenya, E. S.; Solov'ev, S. M.; Sachenko, V. D.; Gall, L. N.; Zarutskii, I. V.; Gall, N. R.

    2013-05-01

    A specialized isotope mass spectrometer for noninvasive diagnostics of Helicobacter pylori infection in human beings based on the carbon-13 isotope breath test has been designed and constructed. Important stages of the work included (i) calculating a low-aberration mass analyzer, (ii) manufacturing and testing special gas inlet system, and (iii) creating a small-size collector of ions. The proposed instrument ensures 13C/12C isotopic ratio measurement to within 1.7‰ (pro mille) accuracy, which corresponds to requirements for a diagnostic tool. Preliminary medical testing showed that the mass spectrometer is applicable to practical diagnostics. The instrument is also capable of measuring isotopic ratios of other light elements, including N, O, B (for BF2+ ions), Ar, Cl, and S.

  4. Dual mode ion mobility spectrometer and method for ion mobility spectrometry

    DOEpatents

    Scott, Jill R [Idaho Falls, ID; Dahl, David A [Idaho Falls, ID; Miller, Carla J [Idaho Falls, ID; Tremblay, Paul L [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

    2007-08-21

    Ion mobility spectrometer apparatus may include an ion interface that is operable to hold positive and negative ions and to simultaneously release positive and negative ions through respective positive and negative ion ports. A first drift chamber is operatively associated with the positive ion port of the ion interface and encloses an electric field therein. A first ion detector operatively associated with the first drift chamber detects positive ions from the first drift chamber. A second drift chamber is operatively associated with the negative ion port of the ion interface and encloses an electric field therein. A second ion detector operatively associated with the second drift chamber detects negative ions from said second drift chamber.

  5. A Novel 9.4 Tesla FTICR Mass Spectrometer with Improved Sensitivity, Mass Resolution, and Mass Range

    NASA Astrophysics Data System (ADS)

    Kaiser, Nathan K.; Quinn, John P.; Blakney, Gregory T.; Hendrickson, Christopher L.; Marshall, Alan G.

    2011-08-01

    Fourier transform ion cyclotron resonance (FTICR) mass spectrometry provides unparalleled mass measurement accuracy and resolving power. However, propagation of the technique into new analytical fields requires continued advances in instrument speed and sensitivity. Here, we describe a substantial redesign of our custom-built 9.4 tesla FTICR mass spectrometer that improves sensitivity, acquisition speed, and provides an optimized platform for future instrumentation development. The instrument was designed around custom vacuum chambers for improved ion optical alignment, minimized distance from the external ion trap to magnetic field center, and high conductance for effective differential pumping. The length of the transfer optics is 30% shorter than the prior system, for reduced time-of-flight mass discrimination and increased ion transmission and trapping efficiency at the ICR cell. The ICR cell, electrical vacuum feedthroughs, and cabling have been improved to reduce the detection circuit capacitance (and improve detection sensitivity) 2-fold. The design simplifies access to the ICR cell, and the modular vacuum flange accommodates new ICR cell technology, including linearized excitation, high surface area detection, and tunable electrostatic trapping potential.

  6. A Carbon Nano Tube electron impact ionisation source for low-power, compact spacecraft mass spectrometers

    NASA Astrophysics Data System (ADS)

    Sheridan, S.; Bardwell, M. W.; Morse, A. D.; Morgan, G. H.

    2012-04-01

    A novel ionisation source which uses commercially available Carbon Nano Tube devices is demonstrated as a replacement for a filament based ionisation source in an ion trap mass spectrometer. The carbon nanotube ion source electron emission was characterised and exhibited typical emission of 30 ± 1.7 μA with an applied voltage differential of 300 V between the carbon nanotube tips and the extraction grid. The ion source was tested for longevity and operated under a condition of continuous emission for a period of 44 h; there was an observed reduction in emission current of 26.5% during operation. Spectra were generated by installing the ion source into a Finnigan Mat ITD700 ion trap mass spectrometer; the spectra recorded showed all of the characteristic m/z peaks from m/z 69 to m/z 219. Perfluorotributylamine spectra were collected and averaged contiguously for a period of 48 h with no significant signal loss or peak mass allocation shift. The low power requirements and low mass of this novel ionisation source are considered be of great value to future space missions where mass spectrometric technology will be employed.

  7. Dynamics Explorer 1: Energetic Ion Composition Spectrometer (EICS)

    NASA Technical Reports Server (NTRS)

    Shelley, E. G.; Peterson, W. K.; Collin, H. L.

    1994-01-01

    The Energetic Ion Composition Spectrometer (EICS) experiment was selected as part of the Dynamics Explorer (DE) Program. One of the primary goals of the DE program was to investigate in detail the plasma physics processes responsible for energizing thermal (approximately 1 eV) ionospheric ions and transporting them to the earth's plasma sheet and distant polar cap. The results of the EICS data analysis (including support of other investigators) and of the archiving efforts supported by this contract are summarized in this document. Also reported are some aspects of our operational support activities.

  8. A five-collector system for the simultaneous measurement of argon isotope ratios in a static mass spectrometer

    USGS Publications Warehouse

    Stacey, J.S.; Sherrill, N.D.; Dalrymple, G.B.; Lanphere, M.A.; Carpenter, N.V.

    1981-01-01

    A system is described that utilizes five separate Faraday-cup collector assemblies, aligned along the focal plane of a mass spectrometer, to collect simultaneous argon ion beams at masses 36-40. Each collector has its own electrometer amplifier and analog-to-digital measuring channel, the outputs of which are processed by a minicomputer that also controls the mass spectrometer. The mass spectrometer utilizes a 90?? sector magnetic analyzer with a radius of 23 cm, in which some degree of z-direction focussing is provided for all the ion beams by the fringe field of the magnet. Simultaneous measurement of the ion beams helps to eliminate mass-spectrometer memory as a significant source of measurement error during an analysis. Isotope ratios stabilize between 7 and 9 s after sample admission into the spectrometer, and thereafter changes in the measured ratios are linear, typically to within ??0.02%. Thus the multi-collector arrangement permits very short extrapolation times for computation of initial ratios, and also provides the advantages of simultaneous measurement of the ion currents in that errors due to variations in ion beam intensity are minimized. A complete analysis takes less than 10 min, so that sample throughput can be greatly enhanced. In this instrument, the factor limiting analytical precision now lies in short-term apparent variations in the interchannel calibration factors. ?? 1981.

  9. The History of Planetary Exploration Using Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    Mahaffy, Paul R.

    2012-01-01

    At the Planetary Probe Workshop Dr. Paul Mahaffy will give a tutorial on the history of planetary exploration using mass spectrometers. He will give an introduction to the problems and solutions that arise in making in situ measurements at planetary targets using this instrument class.

  10. Development of an ion time-of-flight spectrometer for neutron depth profiling

    NASA Astrophysics Data System (ADS)

    Cetiner, Mustafa Sacit

    signal. Without loss of generality, the secondary signal is obtained by the passage of the ion through a thin carbon foil, which produces ion-induced secondary electron emission (IISEE). The time-of-flight spectrometer physically acts as an ion/electron separator. The electrons that enter the active volume of the spectrometer are transported onto the microchannel plate detector to generate the secondary signal. The electron optics can be designed in variety of ways depending on the nature of the measurement and physical requirements. Two ion time-of-flight spectrometer designs are introduced: the parallel electric and magnetic (PEM) field spectrometer and the cross electric and magnetic (CEM) field spectrometer. The CEM field spectrometers have been extensively used in a wide range of applications where precise mass differentiation is required. The PEM field spectrometers have lately found interest in mass spectroscopy applications. The application of the PEM field spectrometer for energy measurements is a novel approach. The PEM field spectrometer used in the measurements employs axial electric and magnetic fields along the nominal direction of the incident ion. The secondary electrons are created by a thin carbon foil on the entrance disk and transported on the microchannel plate that faces the carbon foil. The initial angular distribution of the secondary electrons has virtually no effect on the transport time of the secondary electrons from the surface of the carbon foil to the electron microchannel plate detector. Therefore, the PEM field spectrometer can offer high-resolution energy measurement for relatively lower electric fields. The measurements with the PEM field spectrometer were made with the Tandem linear particle accelerator at the IBM T. J. Watson Research Center at Yorktown Heights, NY. The CEM field spectrometer developed for the thesis employs axial electric field along the nominal direction of the ion, and has perpendicular magnetic field. As the

  11. Rapid scanning mass spectrometer. Final CRADA report for CRADA Number Y-1295-0394

    SciTech Connect

    Leckey, J.H.; Boeckmann, M.D.

    1997-02-24

    This Cooperative Research and Development Agreement was used to modify Vacuum Technology`s AERO VAC computer/mass spectrometer interface and electronics to allow the mass spectrometer to acquire rapid scans. The computer interface sends signals from the PC to the mass spectrometer, controlling its filament, giving scan instructions, and selecting the proper electrometer range, and detector. It then receives the detector output in the form of amplified digital signals from the electrometer. This project performed the following three upgrades on the computer interface and electronics. (1) A new electrometer was designed and built to process the signal from the detector. This new electrometer is more sensitive, over 10 times faster, and over 100 times more stable than the electrometer it will have replaced. (2) The controller EPROM was reprogrammed with new firmware. This firmware acts as an operating system for the interface and is used to shuttle communications between the PC and the AERO VAC mass spectrometer. The new firmware allows digital signals to be transmitted considerably faster to and from the mass spectrometer than the old firmware. The voltage regulator which causes the ion selector voltage to ramp to allow ions of selected mass to be sequentially detected was redesigned and prototyped. The redesign allowed obsolete electronics in the regulator circuitry to be replaced with more efficient circuitry. The redesigned voltage regulator can be ramped up or down more than 100 times faster than the existing regulator. Figure 4 shows a picture of the prototype voltage regulator circuit. These changes were incorporated into a prototype unit and preliminary performance testing conducted. Results indicated that scanning speed was significantly increased over the unmodified version.

  12. Negative thermal ion mass spectrometry of osmium, rhenium, and iridium

    NASA Technical Reports Server (NTRS)

    Creaser, R. A.; Papanastassiou, D. A.; Wasserburg, G. J.

    1991-01-01

    This paper describes a technique for obtaining, in a conventional surface ionization mass spectrometer, intense ion beams of negatively charged oxides of Os, Re, and Ir by thermal ionization. It is shown that the principal ion species of these ions are OsO3(-), ReO4(-), and IrO2(-), respectively. For Re-187/Os-187 studies, this technique offers the advantage of isotopic analyses without prior chemical separation of Re from Os.

  13. Laser Induced-Plasma Ion Mass Spectrometry for Characterization of Lunar and Planetary Surfaces

    NASA Astrophysics Data System (ADS)

    Wiens, R. C.; Blacic, J. D.; Cremers, D. A.; Ritzau, S. M.; Nordholt, J. E.; Funsten, H. O.

    1999-03-01

    LIMS is being developed to perform isotopic and elemental analysis of lunar and planetary surfaces at standoff distances. It uses an advanced ion mass spectrometer to obtain mass and energy spectra from the ionized plume produced by a laser.

  14. H2 production by ice grains impacts in the Cassini Ion and Neutral Mass Spectrometer at Enceladus: Modeling of the total amount by flyby to constrain the quantity of H2 in the plumes

    NASA Astrophysics Data System (ADS)

    Bouquet, Alexis; Brockwell, Tim; Waite, J. Hunter; Chocron, Sidney; Teolis, Ben; Perryman, Rebecca; Walker, James; Cassini-INMS

    2016-10-01

    The data from the closed source of the Cassini-Ion and Neutral Mass Spectrometer (INMS) at Enceladus' plumes shows presence of H2 but the detected quantities are dependant on spacecraft velocity. This is attributed to the presence of ice grains in the plumes: their impacts on the walls of the titanium antechamber of INMS' closed source expose/project fresh titanium that will react with water to form H2. The large number of small ice grains arriving during a single integration period of INMS creates a background signal in addition of large grains causing punctual spikes. ). This poses the question of how much of the detected hydrogen is native and how much is an artifact. Signficant quantities of native H2 could be considered as a "smoking gun" for the suspected hydrothermal activity in Enceladus' ocean as it is ultravolatile and would need to be the result of an ongoing production.A surface chemistry model of the INMS has been developed in order to determine how much H2 is produced from the expected ice grains distribution for each flyby. This model considers adsorption and chemisorption effects to follow the evolution of surface and gas phase species in the antechamber. It estimates production of titanium from results of multiple CTH simulations of impacts of ice grains on a titanium surface.Low velocity (7.5 km/s) impacts produce mostly solid titanium that causes a slow and persistent production of H2, inducing a mass 2 signal after the spacecraft has exited the plume. This persistent signal is key to the evaluation of the total quantity of titanium released, and therefore H2 produced, during the flyby.However the quasi-instant reaction of the titanium fragments with the surrounding water vapor creates an additional difficulty. An adiabatic expansion model of the cloud is used to estimate how much of the titanium is immediately reacted.We discuss how the simulation results compare to observations, both in term of background signal and in creating spikes from big

  15. Atomic oxygen-metal surface studies as applied to mass spectrometer measurements of upper planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Sjolander, G. W.

    1976-01-01

    The problem of atomic oxygen loss in mass spectrometer ion sources can be reduced to an understanding of the possible surface interactions between oxygen atoms and the metal surface of the ion source. Results are presented for an experimental study in which an atomic oxygen beam apparatus and a mass spectrometer were used to measure the oxygen atom reflection, recombination, general surface reaction, and occlusion probabilities on six different engineering surfaces as a function of atomic oxygen exposure. The materials studied are gold, Nichrome V, aluminum, titanium, silver, and platinum. The variation in measured reflection probability seems to occur with metals that form oxides, Nichrome V being stable in terms of reflection stability. Recombination is observed an all surfaces except aluminum and platinum. Variation in the complete set of measurements in a single experiment is the result of varying surface conditions.

  16. A new mass spectrometer system for investigating laser-induced vaporization phenomena

    NASA Technical Reports Server (NTRS)

    Lincoln, K. A.

    1974-01-01

    A laser has been combined with a mass spectrometer in a new configuration developed for studies of high-temperature materials. A vacuum-lock, solid-sample inlet is mounted at one end of a cylindrical, high-vacuum chamber one meter in length with a nude ion-source, time-of-flight mass spectrometer at the opposite end. The samples are positioned along the axis of the chamber at distances up to one meter from the ion source, and their surfaces are vaporized by a pulsed laser beam entering via windows on one side of the chamber. The instrumentation along with its capabilities is described, and results from laser-induced vaporization of several graphites are presented.

  17. Probe Heating Method for the Analysis of Solid Samples Using a Portable Mass Spectrometer

    PubMed Central

    Kumano, Shun; Sugiyama, Masuyuki; Yamada, Masuyoshi; Nishimura, Kazushige; Hasegawa, Hideki; Morokuma, Hidetoshi; Inoue, Hiroyuki; Hashimoto, Yuichiro

    2015-01-01

    We previously reported on the development of a portable mass spectrometer for the onsite screening of illicit drugs, but our previous sampling system could only be used for liquid samples. In this study, we report on an attempt to develop a probe heating method that also permits solid samples to be analyzed using a portable mass spectrometer. An aluminum rod is used as the sampling probe. The powdered sample is affixed to the sampling probe or a droplet of sample solution is placed on the tip of the probe and dried. The probe is then placed on a heater to vaporize the sample. The vapor is then introduced into the portable mass spectrometer and analyzed. With the heater temperature set to 130°C, the developed system detected 1 ng of methamphetamine, 1 ng of amphetamine, 3 ng of 3,4-methylenedioxymethamphetamine, 1 ng of 3,4-methylenedioxyamphetamine, and 0.3 ng of cocaine. Even from mixtures consisting of clove powder and methamphetamine powder, methamphetamine ions were detected by tandem mass spectrometry. The developed probe heating method provides a simple method for the analysis of solid samples. A portable mass spectrometer incorporating this method would thus be useful for the onsite screening of illicit drugs. PMID:26819909

  18. Probe Heating Method for the Analysis of Solid Samples Using a Portable Mass Spectrometer.

    PubMed

    Kumano, Shun; Sugiyama, Masuyuki; Yamada, Masuyoshi; Nishimura, Kazushige; Hasegawa, Hideki; Morokuma, Hidetoshi; Inoue, Hiroyuki; Hashimoto, Yuichiro

    2015-01-01

    We previously reported on the development of a portable mass spectrometer for the onsite screening of illicit drugs, but our previous sampling system could only be used for liquid samples. In this study, we report on an attempt to develop a probe heating method that also permits solid samples to be analyzed using a portable mass spectrometer. An aluminum rod is used as the sampling probe. The powdered sample is affixed to the sampling probe or a droplet of sample solution is placed on the tip of the probe and dried. The probe is then placed on a heater to vaporize the sample. The vapor is then introduced into the portable mass spectrometer and analyzed. With the heater temperature set to 130°C, the developed system detected 1 ng of methamphetamine, 1 ng of amphetamine, 3 ng of 3,4-methylenedioxymethamphetamine, 1 ng of 3,4-methylenedioxyamphetamine, and 0.3 ng of cocaine. Even from mixtures consisting of clove powder and methamphetamine powder, methamphetamine ions were detected by tandem mass spectrometry. The developed probe heating method provides a simple method for the analysis of solid samples. A portable mass spectrometer incorporating this method would thus be useful for the onsite screening of illicit drugs.

  19. Underwater mass spectrometers for in situ chemical analysis of the hydrosphere.

    PubMed

    Short, R T; Fries, D P; Kerr, M L; Lembke, C E; Toler, S K; Wenner, P G; Byrne, R H

    2001-06-01

    Underwater mass spectrometry systems can be used for direct in situ detection of volatile organic compounds and dissolved gases in oceans, lakes, rivers and waste-water streams. In this work we describe the design and operation of (1) a linear quadrupole mass filter and (2) a quadrupole ion trap mass spectrometer interfaced, in each case, with a membrane introduction/fluid control system and packaged for underwater operation. These mass spectrometry systems can operate autonomously, or under user control via a wireless rf link. Detection limits for each system were determined in the laboratory using pure solutions. The quadrupole mass filter system provides detection limits in the 1-5 ppb range with an upper mass limit of 100 amu. Its power requirement is approximately 95 Watts. The ion trap system has detection limits well below 1 ppb, an upper mass limit of 650 amu and MS/MS capability. Its power consumption is on the order of 150 Watts. The present membrane limits analysis to non-polar compounds (<300 amu) with analysis cycles of 5-15 minutes. Deployments of both types of instruments are described, along with a discussion of the challenges associated with in-water mass spectrometry and descriptions of alternative in-water mass spectrometer configurations.

  20. Halley comet dust particle classification according to the data obtained by mass spectrometer Puma-2

    NASA Astrophysics Data System (ADS)

    Dikov, Yu. P.; Evlanov, E. N.; Fomenkova, M. N.; Mukhin, L. M.; Nazarov, M. A.; Prilutsky, O. F.; Sagdeev, R. Z.; Zubkov, B. V.

    Nonzero mode spectra of the dust component of Comet Halley obtained by the dust particle impact mass-spectrometer, Puma-1, on Vega, are used to examine the origin of the mineral phase. The element compositions of 511 cometary particles are studied, using data on ions of Na, Ca, C, H, N, S, Si, Mg, Fe, Cr, and Al. The results are used to determine the mineral composition of the dust of Comet Halley.

  1. A new, highly sensitive time-of-flight mass spectrometer consisting of a flangeon-type conical ion lens system and a proto-type Daly detector for exhaust gas analysis based on the Jet-REMPI technique.

    PubMed

    Suzuki, Tetsuya; Hayashi, Shun-ichi; Ishiuchi, Shun-ichi; Saeki, Morihisa; Fujii, Masaaki

    2005-08-01

    For the analysis of trace amounts of hazardous organic compounds, we developed a new ion detection system for supersonic jet resonance-enhanced multiphoton laser ionization mass spectrometry. High sensitivity and selectivity have been achieved by combining a proto-type Daly detector, a newly designed conical ion lens, and a potential switch that can perform the function of a mass selector. This ion detection system enables us to bring the jet nozzle closer to the ionization point. The detection sensitivity has thus been improved totally by more than 100 times compared with that obtained by the parallel-plate electrodes and micro-channel plate. We succeeded in assembling a flangeon-type ion extraction electrode consisting of a conical ion lens and a potential switch.

  2. Dynamic multiplexed analysis method using ion mobility spectrometer

    SciTech Connect

    Belov, Mikhail E

    2010-05-18

    A method for multiplexed analysis using ion mobility spectrometer in which the effectiveness and efficiency of the multiplexed method is optimized by automatically adjusting rates of passage of analyte materials through an IMS drift tube during operation of the system. This automatic adjustment is performed by the IMS instrument itself after determining the appropriate levels of adjustment according to the method of the present invention. In one example, the adjustment of the rates of passage for these materials is determined by quantifying the total number of analyte molecules delivered to the ion trap in a preselected period of time, comparing this number to the charge capacity of the ion trap, selecting a gate opening sequence; and implementing the selected gate opening sequence to obtain a preselected rate of analytes within said IMS drift tube.

  3. Development of an Atmospheric Pressure Ionization Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    1998-01-01

    A commercial atmospheric pressure ionization mass spectrometer (APIMS) was purchased from EXTREL Mass Spectrometry, Inc. (Pittsburgh, PA). Our research objectives were to adapt this instrument and develop techniques for real-time determinations of the concentrations of trace species in the atmosphere. The prototype instrument is capable of making high frequency measurements with no sample preconcentrations. Isotopically labeled standards are used as an internal standard to obtain high precision and to compensate for changes in instrument sensitivity and analyte losses in the sampling manifold as described by Bandy and coworkers. The prototype instrument is capable of being deployed on NASA C130, Electra, P3, and DC8 aircraft. After purchasing and taking delivery by June 1994, we assembled the mass spectrometer, data acquisition, and manifold flow control instrumentation in electronic racks and performed tests.

  4. Electron-Induced Dissociation of Peptides in a Triple Quadrupole Mass Spectrometer Retrofitted with an Electromagnetostatic Cell

    NASA Astrophysics Data System (ADS)

    Voinov, Valery G.; Bennett, Samuel E.; Barofsky, Douglas F.

    2015-05-01

    Dissociation of peptides induced by interaction with (free) electrons (electron-induced dissociation, EID) at electron energies ranging from near 0 to >30 eV was carried out using a radio-frequency-free electromagnetostatic (EMS) cell retrofitted into a triple quadrupole mass spectrometer. The product-ion mass spectra exhibited EID originating from electronically excited even-electron precursor ions, reduced radical cations formed by capture of low-energy electrons, and oxidized radical cations produced by interaction with high-energy electrons. The spectra demonstrate, within the limits of the triple quadrupole's resolving power, that high-energy EID product-ion spectra produced with an EMS cell exhibit essentially the same qualitative structural information, i.e., amino acid side-chain (SC) losses and backbone cleavages, as observed in high-energy EID spectra produced with a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. The levels of fragmentation efficiency evident in the product-ion spectra recorded in this study, as was the case for those recorded in earlier studies with FT ICR mass spectrometers, is currently at the margin of analytical utility. Given that this shortcoming can be remedied, EMS cells incorporated into QqQ or QqTOF mass spectrometers could make tandem high-energy EID mass spectrometry more widely accessible for analysis of peptides, small singly charged molecules, pharmaceuticals, and clinical samples.

  5. Note: A novel dual-channel time-of-flight mass spectrometer for photoelectron imaging spectroscopy

    SciTech Connect

    Qin Zhengbo; Wu Xia; Tang Zichao

    2013-06-15

    A novel dual-channel time-of-flight mass spectrometer (D-TOFMS) has been designed to select anions in the photoelectron imaging measurements. In this instrument, the radiation laser can be triggered precisely to overlap with the selected ion cloud at the first-order space focusing plane. Compared with that of the conventional single channel TOFMS, the in situ mass selection performance of D-TOFMS is significantly improved. Preliminary experiment results are presented for the mass-selected photodetachment spectrum of F{sup -} to demonstrate the capability of the instrument.

  6. A Low-cost, Lightweight, and Miniaturized Time-of-flight Mass Spectrometer (TOFMS)

    NASA Technical Reports Server (NTRS)

    Srivastava, S. K.

    1993-01-01

    Time-of-flight mass spectrometers (TOFMS) are commonly used for mass analysis and for the measurement of energy distributions of charged particles. For achieving high mass and energy resolution these instruments generally comprise long flight tubes, often as long as a few meters. This necessitates high voltages and a very clean environment. These requirements make them bulky and heavy. We have developed an instrument and calibration techniques that are based on the design principles of TOFMS. However, instead of one long flight tube it consists of a series of cylindrical electrostatic lenses that confine ions under study along the axis of the flight tube.

  7. High sensitivity pulse-counting mass spectrometer system for noble gas analysis

    NASA Technical Reports Server (NTRS)

    Hohenberg, C. M.

    1980-01-01

    A pulse-counting mass spectrometer is described which is comprised of a new ion source of cylindrical geometry, with exceptional optical properties (the Baur source), a dual focal plane externally adjustable collector slits, and a 17-stage Allen-type electron multiplier, all housed in a metal 21 cm radius, 90 deg magnetic sector flight tube. Mass discrimination of the instrument is less than 1 per mil per mass unit; the optical transmission is more than 90%; the source sensitivity (Faraday collection) is 4 ma/torr at 250 micron emission; and the abundance sensitivity is 30,000.

  8. High Mass Accuracy and High Mass Resolving Power FT-ICR Secondary Ion Mass Spectrometry for Biological Tissue Imaging

    SciTech Connect

    Smith, Donald F.; Kiss, Andras; Leach, Franklin E.; Robinson, Errol W.; Pasa-Tolic, Ljiljana; Heeren, Ronald M.

    2013-07-01

    Biological tissue imaging by secondary ion mass spectrometry has seen rapid development with the commercial availability of polyatomic primary ion sources. Endogenous lipids and other small bio-molecules can now be routinely mapped on the micrometer scale. Such experiments are typically performed on time-of-flight mass spectrometers for high sensitivity and high repetition rate imaging. However, such mass analyzers lack the mass resolving power to ensure separation of isobaric ions and the mass accuracy for exact mass elemental formula assignment. We have recently reported a secondary ion mass spectrometer with the combination of a C60 primary ion gun with a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) for high mass resolving power, high mass measurement accuracy and tandem mass spectrometry capabilities. In this work, high specificity and high sensitivity secondary ion FT-ICR MS was applied to chemical imaging of biological tissue. An entire rat brain tissue was measured with 150 μm spatial resolution (75 μm primary ion spot size) with mass resolving power (m/Δm50%) of 67,500 (at m/z 750) and root-mean-square measurement accuracy less than two parts-per-million for intact phospholipids, small molecules and fragments. For the first time, ultra-high mass resolving power SIMS has been demonstrated, with m/Δm50% > 3,000,000. Higher spatial resolution capabilities of the platform were tested at a spatial resolution of 20 μm. The results represent order of magnitude improvements in mass resolving power and mass measurement accuracy for SIMS imaging and the promise of the platform for ultra-high mass resolving power and high spatial resolution imaging.

  9. A miniature laser ablation time-of-flight mass spectrometer for in situ planetary exploration

    NASA Astrophysics Data System (ADS)

    Rohner, Urs; Whitby, James A.; Wurz, Peter

    2003-12-01

    We report the development and testing of a miniature mass spectrometer and ion source intended to be deployed on an airless planetary surface to measure the elemental and isotopic composition of rocks and soils. Our design concentrates at this stage on the proposed BepiColombo mission to the planet Mercury. The mass analyser is an axially symmetric reflectron time-of-flight design. The ion source utilizes a laser induced plasma, which is directly coupled into the mass analyser. Laser ablation gives high spatial resolution, and avoids the need for sample preparation. Our prototype instrument has a demonstrated mass resolution m/Dgrm (FWHM) in excess of 600 and a predicted dynamic range of better than four orders of magnitude. Isotopic fractionation effects are found to be minor. We estimate that a flight instrument would have a mass of 500 g (including all electronics), a volume of 650 cm3 and could operate on 3 W power.

  10. High energy collisions on tandem time-of-flight mass spectrometers.

    PubMed

    Cotter, Robert J

    2013-05-01

    Long before the introduction of matrix-assisted laser desorption/ionization (MALDI), electrospray ionization (ESI), Orbitraps, and any of the other tools that are now used ubiquitously for proteomics and metabolomics, the highest performance mass spectrometers were sector instruments, providing high resolution mass measurements by combining an electrostatic energy analyzer (E) with a high field magnet (B). In its heyday, the four sector mass spectrometer (or EBEB) was the crown jewel, providing the highest performance tandem mass spectrometry using single, high energy collisions to induce fragmentation. During a time in which quadrupole and tandem triple quadrupole instruments were also enjoying increased usage and popularity, there were, nonetheless, some clear advantages for sectors over their low collision energy counterparts. Time-of-flight (TOF) mass spectrometers are high voltage, high vacuum instruments that have much in common with sectors and have inspired the development of tandem instruments exploiting single high energy collisions. In this retrospective, we recount our own journey to produce high performance TOFs and tandem TOFs, describing the basic theory, problems, and the advantages for such instruments. An experiment testing impulse collision theory (ICT) underscores the similarities with sector mass spectrometers where this concept was first developed. Applications provide examples of more extensive fragmentation, side chain cleavages, and charge-remote fragmentation, also characteristic of high energy sector mass spectrometers. Moreover, the so-called curved-field reflectron has enabled the design of instruments that are simpler, collect and focus all of the ions, and may provide the future technology for the clinic, for tissue imaging, and the characterization of microorganisms.

  11. Carbohydrate Structure Characterization by Tandem Ion Mobility Mass Spectrometry (IMMS)2

    PubMed Central

    Li, Hongli; Bendiak, Brad; Siems, William F.; Gang, David R.; Hill, Herbert H.

    2013-01-01

    A high resolution ion mobility spectrometer was interfaced to a Synapt G2 high definition mass spectrometer (HDMS) to produce IMMS-IMMS analysis. The hybrid instrument contained an electro-spray ionization source, two ion gates, an ambient pressure linear ion mobility drift tube, a quadrupole mass filter, a traveling wave ion mobility spectrometer (TWIMS) and a time of flight mass spectrometer. The dual gate drift tube ion mobility spectrometer (DTIMS) could be used to acquire traditional IMS spectra, but also could selectively transfer specific mobility selected precursor ions to the Synapt G2 HDMS for mass filtration (quadrupole). The mobility and mass selected ions could then be introduced into a collision cell for fragmentation followed by mobility separation of the fragment ions with the traveling wave ion mobility spectrometer. These mobility separated fragment ions are finally mass analyzed using a time-of-flight mass spectrometer. This results in an IMMS-IMMS analysis and provides a method to evaluate the isomeric heterogeneity of precursor ions by both DTIMS and TWIMS, to acquire a mobility-selected and mass-filtered fragmentation pattern and to additionally obtain traveling wave ion mobility spectra of the corresponding product ions. This new IMMS2 instrument enables the structural diversity of carbohydrates to be studied in greater detail. The physical separation of isomeric oligosaccharide mixtures was achieved by both DTIMS and TWIMS, with DTIMS demonstrating higher resolving power (70~80) than TWIMS (30~40). Mobility selected MS/MS spectra were obtained, and TWIMS evaluation of product ions showed that isomeric forms of fragment ions existed for identical m/z values. PMID:23330948

  12. Carbohydrate structure characterization by tandem ion mobility mass spectrometry (IMMS)2.

    PubMed

    Li, Hongli; Bendiak, Brad; Siems, William F; Gang, David R; Hill, Herbert H

    2013-03-05

    A high resolution ion mobility spectrometer was interfaced to a Synapt G2 high definition mass spectrometer (HDMS) to produce IMMS-IMMS analysis. The hybrid instrument contained an electrospray ionization source, two ion gates, an ambient pressure linear ion mobility drift tube, a quadrupole mass filter, a traveling wave ion mobility spectrometer (TWIMS), and a time-of-flight mass spectrometer. The dual gate drift tube ion mobility spectrometer (DTIMS) could be used to acquire traditional IMS spectra but also could selectively transfer specific mobility selected precursor ions to the Synapt G2 HDMS for mass filtration (quadrupole). The mobility and mass selected ions could then be introduced into a collision cell for fragmentation followed by mobility separation of the fragment ions with the traveling wave ion mobility spectrometer. These mobility separated fragment ions are finally mass analyzed using a time-of-flight mass spectrometer. This results in an IMMS-IMMS analysis and provides a method to evaluate the isomeric heterogeneity of precursor ions by both DTIMS and TWIMS to acquire a mobility-selected and mass-filtered fragmentation pattern and to additionally obtain traveling wave ion mobility spectra of the corresponding product ions. This new IMMS(2) instrument enables the structural diversity of carbohydrates to be studied in greater detail. The physical separation of isomeric oligosaccharide mixtures was achieved by both DTIMS and TWIMS, with DTIMS demonstrating higher resolving power (70-80) than TWIMS (30-40). Mobility selected MS/MS spectra were obtained, and TWIMS evaluation of product ions showed that isomeric forms of fragment ions existed for identical m/z values.

  13. High-energy collision induced dissociation fragmentation pathways of peptides, probed using a multiturn tandem time-of-flight mass spectrometer 'MULTUM-TOF/TOF'

    SciTech Connect

    Toyoda, Michisato; Giannakopulos, Anastassios E.; Colburn, Alex W.; Derrick, Peter J.

    2007-07-15

    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.

  14. Shuttle Upper Atmosphere Mass Spectrometer Experimental Flight Results

    NASA Technical Reports Server (NTRS)

    Blanchard, R. C.; Ozoroski, Thomas A.; Nicholson, John Y.

    1994-01-01

    Calibrated pressure measurements for species with mass-to-charge ratios up to 50 amu/e(-) were obtained trom the shuttle upper atmosphere mass spectrometer experiment during re-entry on the STS-35 mission. The principal experimental objective is to obtain measurements of freestream density in the hypersonic rarefied flow flight regime. Data were collected from 180 to about 87 km. However, data above 115 km were contaminated from a source of gas emanating from pressure transdueers connected in parallel to the mass spectrometer. At lower altitudes, the pressure transducer data are compared to the mass spectrometer total pressure with excellent agreement. Near the orifice entrance, a significant amount of CO2 was generated from chemical reactions. The freestream density in the rarefied flow flight regime is calculated using an orifice pressure coefficient model based upon direct simulation Monte Carlo results. This density, when compared with the 1976 U.S. Standard Atmosphere model, exhibits the wavelike nature seen on previous flights using accelerometry. Selected spectra are presented at higher altitudes (320 km) showing the effects of the ingestion of gases from a forward fuselage fuel dump.

  15. Influence of Coulomb effects on the resolving power of multireflection mass-spectrometer systems

    SciTech Connect

    Skoblin, M G; Kopaev, I A; Monastyrskiy, M A; Alimpiev, S S; Greenfield, D E; Makarov, A A

    2015-12-31

    General theoretical approaches to the modelling of Coulomb effects in short ion bunches, developed previously by the authors, are applied in this paper to the calculation of multireflection mass-spectrometer systems. A separate module of the MASIM 3D applied software package is designed. An adaptive computational procedure for calculating the 'mirror potential' induced by an ion bunch on the surface of field-forming electrodes is proposed. The dynamics of ion bunches in a time-of-flight reflectron-type mass analyser is calculated and the limitations on the resolving power, caused by resonant Coulomb effects of self-bunching and coalescence in the groups of particles with close masses, are revealed on the basis of numerical experiments. (laser applications and other topics in quantum electronics)

  16. C60 Secondary Ion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

    SciTech Connect

    Smith, Donald F.; Robinson, Errol W.; Tolmachev, Aleksey V.; Heeren, Ronald M.; Pasa-Tolic, Ljiljana

    2011-12-15

    Secondary ion mass spectrometry (SIMS) has seen increased application for high spatial chemical imaging of complex biological surfaces. The advent and commercial availability of cluster and polyatomic primary ion sources (e.g. Au and Bi cluster and buckminsterfullerene (C60)) provide improved secondary ion yield and decreased fragmentation of surface species, thus accessibility to intact molecular ions. Despite developments in primary ion sources, development of mass spectrometers to fully exploit their advantages has been limited. Tandem mass spectrometry for identification of secondary ions is highly desirable, but implementation has proven to be difficult. Similarly, high mass resolution and high mass measurement accuracy would greatly improve the chemical specificity of SIMS. Here we combine, for the first time, the advantages of a C60 primary ion source with the ultra-high mass resolving power and high mass measurement accuracy of Fourier transform ion cyclotron resonance mass spectrometry. Mass resolving power in excess of 100,000 (m/Δm50%) is demonstrated, with mass measurement accuracies below 3 parts-per-million. Imaging of mouse brain tissue at 40 μm pixel size is shown. Tandem mass spectrometry of ions from biological tissue is demonstrated and molecular formulae can be assigned to fragment ions.

  17. Absolute calibration of Apollo lunar orbital mass spectrometer.

    NASA Technical Reports Server (NTRS)

    Yeager, P. R.; Smith, A.; Jackson, J. J.; Hoffman, J. H.

    1973-01-01

    Recent experiments were conducted in Langley Research Center's molecular beam system to perform an absolute calibration of the lunar orbital mass spectrometer which was flown on the Apollo 15 and 16 missions. Tests were performed with several models of the instrument using two test gases, argon and neon, in the 1 ntorr to .1 picotorr range. Sensitivity to argon at spacecraft orbital velocity was .00028 A/torr enabling partial pressures in the .01-picotorr range to be measured at the spacecraft altitude. Neon sensitivity was nearly a factor of 5 less. Test data support the feasibility of using the lunar orbital mass spectrometer as a tool to gather information about the lunar atmosphere.

  18. Mass spectrometer. [On Space Transportation System 2 Flight

    NASA Technical Reports Server (NTRS)

    Miller, E. R.; Carignan, G. R.

    1983-01-01

    The quadrupole Mass Spectrometer of the Induced Environment Contamination Monitor (IECM) operates in the range from 2 to 150 amu. It is pointed out that the Mass Spectrometer on STS-2 performed very well. It was found that the column density of H2O effluent from the Shuttle reached a maximum of 1 x 10 to the 13th per sq cm at 7 hr, 30 min and decreased by a factor of 7.5 during the subsequent 40 hrs. The count rate response of H2O could be correlated with mission-related events, taking into account the dumping of supply water, the operation of the Flash Evaporator System, and the firing of a primary reaction control system engine.

  19. In Situ Geochemical Analysis and Age Dating of Rocks Using Laser Ablation-Miniature Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Sinha, Mahadeva P.; Hecht, Michael H.; Hurowitz, Joel A.

    2012-01-01

    A miniaturized instrument for performing chemical and isotopic analysis of rocks has been developed. The rock sample is ablated by a laser and the neutral species produced are analyzed using the JPL-invented miniature mass spectrometer. The direct sampling of neutral ablated material and the simultaneous measurement of all the elemental and isotopic species are the novelties of this method. In this laser ablation-miniature mass spectrometer (LA-MMS) method, the ablated neutral atoms are led into the electron impact ionization source of the MMS, where they are ionized by a 70-eV electron beam. This results in a secondary ion pulse typically 10-100 microsecond wide, compared to the original 5-10-nanosecond laser pulse duration. Ions of different masses are then spatially dispersed along the focal plane of the magnetic sector of the miniature mass spectrometer and measured in parallel by a modified CCD (charge-coupled device) array detector capable of detecting ions directly. Compared to conventional scanning techniques, simultaneous measurement of the ion pulse along the focal plane effectively offers a 100% duty cycle over a wide mass range. LAMMS offers a more quantitative assessment of elemental composition than techniques that detect laser-ionized species produced directly in the ablation process because the latter can be strongly influenced by matrix effects that vary with the structure and geometry of the surface, the laser beam, and the ionization energies of the elements. The measurement of high-precision isotopic ratios and elemental composition of different rock minerals by LAMMS method has been demonstrated. The LA-MMS can be applied for the absolute age determination of rocks. There is no such instrument available presently in a miniaturized version that can be used for NASA space missions. Work is in progress in the laboratory for geochronology of rocks using LA-MMS that is based on K-Ar radiogenic dating technique.

  20. Nanospray ion mobility mass spectrometry of selected high mass species.

    PubMed

    Campuzano, Iain; Giles, Kevin

    2011-01-01

    The introduction of electrospray ionization (ESI) and in particular nano-electrospray (nESI) has enabled the routine mass spectrometric (MS) analysis of large protein complexes in native aqueous buffers. Time-of-flight (ToF) mass spectrometers, in particular the hybrid quadrupole time-of-flight (Q-ToF) instruments, are well suited to the analysis of large protein complexes. When ionized under native-MS conditions, protein complexes routinely exhibit multiple charge states in excess of m/z 6,000, well above the standard mass range of many quadrupole or ion cyclotron-based instruments. The research area of native MS has expanded considerably in the last decade and has shown particular relevance in the area of protein structure determination. Researchers are now able to routinely measure intact MS spectra of protein complexes above 1 MDa in mass. The advent of ion mobility mass spectrometry (IM-MS), in combination with molecular dynamics (MD) studies, is now allowing researchers to infer the shape of the protein complex being analyzed. Herein, we describe how to acquire IM-MS data that ranges from inorganic salt clusters of caesium iodide (CsI) to large biomolecular complexes such as the chaperone protein GroEL.

  1. A novel electrospray-based ion mobility spectrometer

    NASA Astrophysics Data System (ADS)

    Bathgate, Ben; Cheong, Eric C. S.; Backhouse, Christopher J.

    2004-08-01

    We present a design for a low-cost ion mobility spectrometer that can be built using the equipment on hand in many electronics-oriented undergraduate laboratories. The construction of this system is based upon the use of printed circuit boards and does not require the specialized drift and sheath gases, vacuum pumps, heater assemblies, high voltage pulsers, or precision pumps that are characteristic of the systems generally reported in the literature. We demonstrate the system in the separation of ions of methanol and water in air. Despite the low cost of this system it has a performance comparable to more complex systems, with a sensitivity of approximately 100 ppm for the protein cytochrome c. This system is suitable for use as an electronics or signal-processing project, or even a biotechnology demonstration.

  2. Sector field mass spectrometers in ICP-MS

    NASA Astrophysics Data System (ADS)

    Jakubowski, Norbert; Moens, Luc; Vanhaecke, Frank

    1998-11-01

    A new generation of sector field mass spectrometers, with improved analytical figures of merit at even lower prices, is commercially available, giving a strong impetus to the development of inductively coupled plasma mass spectrometry (ICP-MS) sector field instrument applications in the analytical community. It is the aim of this paper to give an overview of these instruments, to introduce some basic concepts, to discuss their peculiarities and performance, and to present some selected examples of analytical applications to demonstrate the `state of the art'.

  3. Evaluating Mass Analyzers as Candidates for Small, Portable, Rugged Single Point Mass Spectrometers for Analysis of Permanent Gases

    NASA Technical Reports Server (NTRS)

    Arkin, C. Richard; Ottens, Andrew K.; Diaz, Jorge A.; Griffin, Timothy P.; Follestein, Duke; Adams, Fredrick; Steinrock, T. (Technical Monitor)

    2001-01-01

    For Space Shuttle launch safety, there is a need to monitor the concentration Of H2, He, O2, and Ar around the launch vehicle. Currently a large mass spectrometry system performs this task, using long transport lines to draw in samples. There is great interest in replacing this stationary system with several miniature, portable, rugged mass spectrometers which act as point sensors which can be placed at the sampling point. Five commercial and two non-commercial analyzers are evaluated. The five commercial systems include the Leybold Inficon XPR-2 linear quadrupole, the Stanford Research (SRS-100) linear quadrupole, the Ferran linear quadrupole array, the ThermoQuest Polaris-Q quadrupole ion trap, and the IonWerks Time-of-Flight (TOF). The non-commercial systems include a compact double focusing sector (CDFMS) developed at the University of Minnesota, and a quadrupole ion trap (UF-IT) developed at the University of Florida.

  4. Optimized electron-optical system of a static mass-spectrometer for simultaneous isotopic and chemical analysis

    NASA Astrophysics Data System (ADS)

    Gall', L. N.; Masyukevich, S. V.; Sachenko, V. D.; Gall', N. R.

    2016-01-01

    A new approach to control the linear dimensions of analytical electrophysical systems is suggested. This approach uses the lens properties of electron-optical elements with a curvilinear axis. It is shown that such an approach can be effectively applied, in particular, to synthesize ion-optical systems (IOSs) for static magnetic mass spectrometers and can be implemented owing to off-axis fundamental points, the "poles" of an electron-optical system, introduced earlier by one of the authors. The capabilities of the new approach are demonstrated with the synthesis of the IOS of a static mass spectrometer dedicated for isotopic and chemical analysis with an increased resolution. A new IOS not only provides desired high ion-optical parameters at decreased dimensions of the mass spectrometer as a whole but also makes it possible to loosen requirements for the manufacturing accuracy of IOS main elements.

  5. A heavy ion spectrometer system for the measurement of projectile fragmentation of relativistic heavy ions

    SciTech Connect

    Engelage, J.; Crawford, H.J.; Greiner, L.; Kuo, C.

    1996-06-01

    The Heavy Ion Spectrometer System (HISS) at the LBL Bevalac provided a unique facility for measuring projectile fragmentation cross sections important in deconvolving the Galactic Cosmic Ray (GCR) source composition. The general characteristics of the apparatus specific to this application are described and the main features of the event reconstruction and analysis used in the TRANSPORT experiment are discussed.

  6. The Multiplexed Chemical Kinetic Photoionization Mass Spectrometer: A New Approach To Isomer-resolved Chemical Kinetics

    SciTech Connect

    Osborne, David L.; Zou, Peng; Johnsen, Howard; Hayden, Carl C.; Taatjes, Craig A.; Knyazev, Vadim D.; North, Simon W.; Peterka, Darcy S.; Ahmed, Musahid; Leone, Stephen R.

    2008-08-28

    We have developed a multiplexed time- and photon-energy?resolved photoionizationmass spectrometer for the study of the kinetics and isomeric product branching of gasphase, neutral chemical reactions. The instrument utilizes a side-sampled flow tubereactor, continuously tunable synchrotron radiation for photoionization, a multi-massdouble-focusing mass spectrometer with 100percent duty cycle, and a time- and positionsensitive detector for single ion counting. This approach enables multiplexed, universal detection of molecules with high sensitivity and selectivity. In addition to measurement of rate coefficients as a function of temperature and pressure, different structural isomers can be distinguished based on their photoionization efficiency curves, providing a more detailed probe of reaction mechanisms. The multiplexed 3-dimensional data structure (intensity as a function of molecular mass, reaction time, and photoionization energy) provides insights that might not be available in serial acquisition, as well as