EP0350159A1 - Verfahren zum Betrieb eines Ionenfallenmassenspektrometers - Google Patents

Verfahren zum Betrieb eines Ionenfallenmassenspektrometers Download PDF

Info

Publication number
EP0350159A1
EP0350159A1 EP19890305618 EP89305618A EP0350159A1 EP 0350159 A1 EP0350159 A1 EP 0350159A1 EP 19890305618 EP19890305618 EP 19890305618 EP 89305618 A EP89305618 A EP 89305618A EP 0350159 A1 EP0350159 A1 EP 0350159A1
Authority
EP
European Patent Office
Prior art keywords
voltage
ions
mass
supplementary
ion trap
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP19890305618
Other languages
English (en)
French (fr)
Inventor
Michael Weber-Grabau
David Brink Tucker
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Thermo Finnigan LLC
Original Assignee
Finnigan Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Finnigan Corp filed Critical Finnigan Corp
Publication of EP0350159A1 publication Critical patent/EP0350159A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/26—Mass spectrometers or separator tubes
    • H01J49/34—Dynamic spectrometers
    • H01J49/42—Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
    • H01J49/4205—Device types
    • H01J49/424—Three-dimensional ion traps, i.e. comprising end-cap and ring electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/26—Mass spectrometers or separator tubes
    • H01J49/34—Dynamic spectrometers
    • H01J49/42—Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
    • H01J49/426—Methods for controlling ions
    • H01J49/427—Ejection and selection methods
    • H01J49/4275—Applying a non-resonant auxiliary oscillating voltage, e.g. parametric excitation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/26—Mass spectrometers or separator tubes
    • H01J49/34—Dynamic spectrometers
    • H01J49/42—Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
    • H01J49/426—Methods for controlling ions
    • H01J49/427—Ejection and selection methods
    • H01J49/429—Scanning an electric parameter, e.g. voltage amplitude or frequency

Definitions

  • This invention relates to a method of operating an ion trap mass spectrometer.
  • Ion trap mass spectrometers or quadrupole ion stores have been known for many years and described by a number of authors. They are devices in which ions are formed and contained within a physical structure by means of hyperbolic electrostatic RF and/or DC fields. In general, RF and/or DC voltages are applied to hyperbolic or spheric electrode structures which define the trapping volume into which the trapping fields extend.
  • the structure generally comprises a ring electrode with spaced end caps.
  • Mass storage is generally achieved by operating the trap electrodes with values of RF voltage V and its frequency f, DC voltage U and device size r0 such that ions having their mass-to-charge ratios (M/Z) within a finite range are stably trapped within the electrostatic fields.
  • the aforementioned parameters are sometimes referred to as the scanning parameters and have a fixed relationship to the mass-to-charge ratios of the charged ions.
  • the characteristic frequencies can be determined by a tuned circuit which couples to the oscillating motions of the ions within the trap. Such a method has been difficult to implement and yields poor resolution and limited mass range.
  • US-A-4540884 there is described a method of operating an ion trap in the mass selective instability mode.
  • the mass selection is achieved by simultaneously trapping ions within a mass range of interest and then scanning the applied RF and/or DC voltages or the frequency of the RF voltage to sequentially render unstable trapped ions of consecutive specific masses.
  • the unstable ions flow out through apertures in an end cap to a high gain electron multiplier to provide signals indicative of the ion mass.
  • a method of operating an ion trap mass spectrometer to render ions within a predetermined range of mass-to-charge ratios trapped in a three-dimensional trapping field generated by a fundamental RF voltage sequentially unstable comprising the steps of varying the fundamental RF voltage to eject ions of sequential mass-to-charge ratios; and simultaneously applying a supplementary AC voltage at a lower frequency to generate a supplementary field whereby the ions of sequential mass-to-charge ratios are more effectively ejected.
  • the suplemental voltage is set at a frequency lower, for example about half, the frequency of the RF voltage, the sensitivity and resolution of the ion trap mass spectrometer can be significantly improved when the ion trap is operated in the mass-selective instability mode.
  • the invention provides a method of operating an ion trap mass spectrometer, which permits the storage of a large number of ions to improved sensitivity while providing the good resolution.
  • a three-dimensional ion trap mass spectrometer is schematically illustrated in Figure 1.
  • the ion trap includes a ring electrode 11 and two spaced end caps 12 and 13 facing each other.
  • the ring electrode and end caps define a trapping volume 14 having a radius r0 and a vertical dimension z0.
  • An RF voltage generator 16 is connected to the ring electrode 11 to supply a radio frequency voltage v sin t (the fundamental voltage) between the end caps and the ring electrode which provides the quadrupole filed for trapping ions within the ion storage volume 14.
  • a DC voltage U from power supply 17 may also be applied to the trap electrodes.
  • a supplementary AC voltage generator 18 is coupled to the end caps 12 and 13 to supply a voltage v2 sin t.
  • Means are provided for projecting an ionizing electron beam into the ion volume 16.
  • the electron source comprises a filament 21 fed by a filament power supply, not shown, and a cylindrical electron gate electrode 22 having a control voltage applied by gate controller 23 to turn the electron beam on and off as desired for ionizing sample within the trapping volume.
  • the end cap 12 includes an axial aperture 24 through which the electron beam projects.
  • the opposite end cap 13 is perforated 26 to allow unstable ions in the fields of the ion trap to exit and be detected by the electron multiplier 27.
  • Conversion dynode 28 is disposed to receive the ejected ions and operates as described in US-A-4423324.
  • the output signal is amplified and applied to processor 29 which not only serves to process the signal and provide a mass spectrum, but also controls operation of the RF, DC and supplemental voltage power supplies and the gate controller to perform an analysis.
  • EI and CI scans are shown in Figure 2A-2B.
  • the EI scan is shown by a solid line while the CI scan is shown by the dotted line.
  • the fundamental RF voltage and DC voltage applied to the ring electrode is selected to store only sample ions of a mass range of interest, A.
  • the sample is introduced in the trapping volume and electron gate voltage is applied to permit the electron beam to enter the volume and ionize the sample.
  • the RF voltage is then ramped to the point B to select the mass range of interest and then the voltage is increased, C, to scan.
  • the scan spectrum is shown in Figure 2C.
  • the voltages are fixed for the period A′ during which the reagent is ionized with reagent ions.
  • the voltage is increased, B′, and the reagent ions then react with neutral sample molecules and form sample ions.
  • the voltage is increased, C′, to select the low mass for start of the scan.
  • the voltage is ramped, D′, to provide the scan spectrum shown in Figure D.
  • ions are formed in the trap volume 16 while maintaining DC and RF voltages so as to store the selected mass range.
  • the trapping voltages are then reduced in such a way that only stable ions of interest are retained at which time a dissociation step is carried on in which the ions of interest are caused to collide with a gas or surface so as to fragment. Since the ions to be fragmented may or may not have sufficient energy to undergo fragmentation by collision with the gas or surface, it may be necessary to pump energy into the ions of interest to cause them to collide with energetic or excited neutral species so the system will contain enough energy to cause fragmentation of the ions of interest. The fragmented ions are then swept from the trap by varying the RF voltage and a scan of the mass spectra is obtained.
  • Excited neutrals of Argon of Xenon may be introduced from a gun, pulsed at a proper time.
  • a discharge source may be used.
  • a laser pulse may be used to pump energy into the system either through ions or through the neutral species.
  • the scanning step in which the ions become sequentially unstable, leave the trap volume and are detected, is accompanied by the application of a supplemental AC voltage to generate fields in the axial direction.
  • the supplemental voltage is applied to both of the end caps or to one of the end caps while the other end cap is grounded.
  • the supplemental AC voltage is preferably selected to have a frequency which is approximately one-half the frequency of the fundamental RF voltage and which causes the trapped ions near the instability boundary to oscillate in the axial direction. This oscillation is the characteristic frequency of ion motion in the z or axial direction and close to the point where the ions become unstable during the mass scan.
  • Figure 4A shows part of the mass spectrum for FC 43, a calibration compound with prominent peaks at m/z 69 and m/z 100. Other mass peaks originate from background in a mass spectrometer. Filament emission current for the experiment was set at 30 microamps and the ionization time was 1.5 msec. A helium buffer gas was present at a pressure of approximately 1 x 10 ⁇ 3 torr. The lack of resolution and peak broadening indicates that the ejection of some ions at a given m/z is extended. That is, some ions are ejected too late and are not resolved from ions of subsequent m/z value.
  • Figure 4B shows the mass spectrum acquired with the exitation voltage turned on during the mass scan at a fixed frequency of 530 KHz and a fixed amplitude of 5 volts. It is noted that the resolution is much improved and that the resolution improvement is observed over the entire mass range of the ion trap.
  • the data shown in Figure 4B was for the exitation voltage being applied only during the analysis scan. Similar results were obtained with the exitation voltage continuously applied.
  • the new scanning mode has been characterised across a wide range of frequencies and amplitudes. Amplitudes were between 1 and 10 volts, frequency between 300 KHz and 600 KHZ.
  • 5A shows the mass spectrum of m/z 284, a characteristic ion, from a GC/MS run of a 10 pg hexachlorobenzene sample in the prior mode of ion trap operation.
  • Figure 5B is the mass spectrum of same sample using the new mode of operation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Electron Tubes For Measurement (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
EP19890305618 1988-06-03 1989-06-05 Verfahren zum Betrieb eines Ionenfallenmassenspektrometers Withdrawn EP0350159A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US20278488A 1988-06-03 1988-06-03
US202784 1988-06-03

Publications (1)

Publication Number Publication Date
EP0350159A1 true EP0350159A1 (de) 1990-01-10

Family

ID=22751247

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890305618 Withdrawn EP0350159A1 (de) 1988-06-03 1989-06-05 Verfahren zum Betrieb eines Ionenfallenmassenspektrometers

Country Status (2)

Country Link
EP (1) EP0350159A1 (de)
JP (1) JPH02103856A (de)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0512700A1 (de) * 1991-04-30 1992-11-11 Finnigan Corporation Verfahren zum Betrieb eines Ionenfalle-Massenspektrometers im hochauflösenden Modus
DE4142869C1 (de) * 1991-12-23 1993-05-19 Bruker - Franzen Analytik Gmbh, 2800 Bremen, De
DE4142871C1 (de) * 1991-12-23 1993-05-19 Bruker - Franzen Analytik Gmbh, 2800 Bremen, De
DE4142870A1 (de) * 1991-12-23 1993-06-24 Bruker Franzen Analytik Gmbh Verfahren und vorrichtung fuer phasenrichtiges messen der ionen aus ionenfallen-massenspektrometern
GB2267385A (en) * 1992-05-29 1993-12-01 Finnigan Corp Ion trap mass spectrometer method
US5381007A (en) * 1991-02-28 1995-01-10 Teledyne Mec A Division Of Teledyne Industries, Inc. Mass spectrometry method with two applied trapping fields having same spatial form
US5436445A (en) * 1991-02-28 1995-07-25 Teledyne Electronic Technologies Mass spectrometry method with two applied trapping fields having same spatial form
US5451782A (en) * 1991-02-28 1995-09-19 Teledyne Et Mass spectometry method with applied signal having off-resonance frequency
US6121610A (en) * 1997-10-09 2000-09-19 Hitachi, Ltd. Ion trap mass spectrometer
GB2423631A (en) * 2005-02-07 2006-08-30 Bruker Daltonic Gmbh Ion fragmentation by reaction with excited neutral particles
RU2372686C2 (ru) * 2004-05-26 2009-11-10 Вэриэн, Инк. Линейная ионная ловушка и способ управления движением иона с использованием асимметричного удерживающего поля
US9202660B2 (en) 2013-03-13 2015-12-01 Teledyne Wireless, Llc Asymmetrical slow wave structures to eliminate backward wave oscillations in wideband traveling wave tubes

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5623144A (en) * 1995-02-14 1997-04-22 Hitachi, Ltd. Mass spectrometer ring-shaped electrode having high ion selection efficiency and mass spectrometry method thereby

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2950389A (en) * 1957-12-27 1960-08-23 Siemens Ag Method of separating ions of different specific charges
EP0113207A2 (de) * 1982-12-29 1984-07-11 Finnigan Corporation Verfahren zur Bestimmung der Masse einer Probe durch eine Quadrupol-Ionentrappe
EP0202943A2 (de) * 1985-05-24 1986-11-26 Finnigan Corporation Steuerungsverfahren für eine Ionenfalle
EP0262928A2 (de) * 1986-10-01 1988-04-06 Finnigan Corporation Quadrupol-Massenspektrometer und Verfahren zum Betrieb desselben
US4749860A (en) * 1986-06-05 1988-06-07 Finnigan Corporation Method of isolating a single mass in a quadrupole ion trap

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2950389A (en) * 1957-12-27 1960-08-23 Siemens Ag Method of separating ions of different specific charges
EP0113207A2 (de) * 1982-12-29 1984-07-11 Finnigan Corporation Verfahren zur Bestimmung der Masse einer Probe durch eine Quadrupol-Ionentrappe
EP0202943A2 (de) * 1985-05-24 1986-11-26 Finnigan Corporation Steuerungsverfahren für eine Ionenfalle
US4749860A (en) * 1986-06-05 1988-06-07 Finnigan Corporation Method of isolating a single mass in a quadrupole ion trap
EP0262928A2 (de) * 1986-10-01 1988-04-06 Finnigan Corporation Quadrupol-Massenspektrometer und Verfahren zum Betrieb desselben

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
International Journal of Mass Spectrometry and Ion Processes, Vol. 60, No. 1, September 1984, pages 85-98, Elsevier, Amsterdam, NL, G.C. STAFFORD et al.: "Recent improvements in and analytical applications of advanced ion trap technology", page 85, lines 13-21; page 90, "Mass analysis by mass selective instability"; figure 1; page 92, lines 36-38. *

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5679951A (en) * 1991-02-28 1997-10-21 Teledyne Electronic Technologies Mass spectrometry method with two applied trapping fields having same spatial form
US5864136A (en) * 1991-02-28 1999-01-26 Teledyne Electronic Technologies Mass spectrometry method with two applied trapping fields having the same spatial form
US5436445A (en) * 1991-02-28 1995-07-25 Teledyne Electronic Technologies Mass spectrometry method with two applied trapping fields having same spatial form
US5561291A (en) * 1991-02-28 1996-10-01 Teledyne Electronic Technologies Mass spectrometry method with two applied quadrupole fields
US5381007A (en) * 1991-02-28 1995-01-10 Teledyne Mec A Division Of Teledyne Industries, Inc. Mass spectrometry method with two applied trapping fields having same spatial form
US5451782A (en) * 1991-02-28 1995-09-19 Teledyne Et Mass spectometry method with applied signal having off-resonance frequency
EP0512700A1 (de) * 1991-04-30 1992-11-11 Finnigan Corporation Verfahren zum Betrieb eines Ionenfalle-Massenspektrometers im hochauflösenden Modus
DE4142869C1 (de) * 1991-12-23 1993-05-19 Bruker - Franzen Analytik Gmbh, 2800 Bremen, De
DE4142871C1 (de) * 1991-12-23 1993-05-19 Bruker - Franzen Analytik Gmbh, 2800 Bremen, De
GB2263193B (en) * 1991-12-23 1995-05-03 Bruker Franzen Analytik Gmbh Method and device for obtaining mass spectra
GB2263193A (en) * 1991-12-23 1993-07-14 Bruker Franzen Analytik Gmbh Ion trap mass spectrometers
GB2263191A (en) * 1991-12-23 1993-07-14 Bruker Franzen Analytik Gmbh Ion trap mass spectrometers
DE4142870A1 (de) * 1991-12-23 1993-06-24 Bruker Franzen Analytik Gmbh Verfahren und vorrichtung fuer phasenrichtiges messen der ionen aus ionenfallen-massenspektrometern
GB2263191B (en) * 1991-12-23 1995-08-30 Bruker Franzen Analytik Gmbh Method and device for recording mass spectra
GB2267385A (en) * 1992-05-29 1993-12-01 Finnigan Corp Ion trap mass spectrometer method
FR2691835A1 (fr) * 1992-05-29 1993-12-03 Finnigan Corp Procédé d'utilisation d'un spectromètre de masse à piège à ions.
GB2267385B (en) * 1992-05-29 1995-12-13 Finnigan Corp Method of detecting the ions in an ion trap mass spectrometer
US6121610A (en) * 1997-10-09 2000-09-19 Hitachi, Ltd. Ion trap mass spectrometer
RU2372686C2 (ru) * 2004-05-26 2009-11-10 Вэриэн, Инк. Линейная ионная ловушка и способ управления движением иона с использованием асимметричного удерживающего поля
GB2423631A (en) * 2005-02-07 2006-08-30 Bruker Daltonic Gmbh Ion fragmentation by reaction with excited neutral particles
US7476853B2 (en) 2005-02-07 2009-01-13 Bruker Daltonik Gmbh Ion fragmentation by reaction with neutral particles
GB2423631B (en) * 2005-02-07 2009-07-01 Bruker Daltonik Gmbh Ion fragmentation by reaction with neutral particles
US9202660B2 (en) 2013-03-13 2015-12-01 Teledyne Wireless, Llc Asymmetrical slow wave structures to eliminate backward wave oscillations in wideband traveling wave tubes

Also Published As

Publication number Publication date
JPH02103856A (ja) 1990-04-16

Similar Documents

Publication Publication Date Title
US4736101A (en) Method of operating ion trap detector in MS/MS mode
US5679951A (en) Mass spectrometry method with two applied trapping fields having same spatial form
JP3064422B2 (ja) 同一の空間形状を持つ２つの捕捉場を用いる質量分析方法
US5075547A (en) Quadrupole ion trap mass spectrometer having two pulsed axial excitation input frequencies and method of parent and neutral loss scanning and selected reaction monitoring
US5466931A (en) Mass spectrometry method using notch filter
EP0529885B1 (de) Multipol-Einlassvorrichtung für Ionenfalle
EP0215615B1 (de) Betriebsverfahren einer Quadrupolionenfalle
US5128542A (en) Method of operating an ion trap mass spectrometer to determine the resonant frequency of trapped ions
US5381006A (en) Methods of using ion trap mass spectrometers
JPH095298A (ja) 四重極イオントラップ内の選択イオン種を検出する方法
US5196699A (en) Chemical ionization mass spectrometry method using notch filter
US5610397A (en) Mass spectrometry method using supplemental AC voltage signals
US5206507A (en) Mass spectrometry method using filtered noise signal
JPH02103856A (ja) イオントラップ型質量分析計の操作方法
US20020162958A1 (en) Ion trap mass spectrometer and spectrometry
EP0575777A2 (de) Verfahren zur Verwendung eines Massenspektrometers
EP0852390B1 (de) Verfahren zum Betreiben eines Ionenfallen-Massenspektrometers

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): CH DE FR GB IT LI NL SE

17P Request for examination filed

Effective date: 19900130

17Q First examination report despatched

Effective date: 19920820

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19930302