Abstract: A mass spectrometer is disclosed comprising an ion mobility spectrometer or separator and an ion guide arranged downstream of the ion mobility spectrometer or separator. A plurality of axial potential wells are created in the ion guide so that ions received from the ion mobility spectrometer or separator become confined in separate axial potential wells. The potential wells maintain the fidelity and/or composition of ions received from the ion mobility spectrometer or separator. The potential wells are translated along the length of the ion guide.

Abstract: Ions having a restricted range of mass to charge ratios are transmitted to the acceleration region of a Time of Flight mass analyzer. A control system applies a first extraction pulse to an acceleration electrode in order to accelerate a first group of ions into the time of flight region at a first time T1, wherein ions having the lowest mass to charge ratio in the first group of ions have a time of flight ?T1min through the time of flight region and ions having the highest mass to charge ratio in the first group of ions have a time of flight ?T1max through the time of flight region. The control system applies a second extraction pulse to the acceleration electrode at a subsequent second time T2, wherein ?T1max??T1min?T2?T1<?T1max.

Abstract: The same sample S is analyzed using an ion-trap (IT) mass spectrometer section 11 in which ions are captured in an ion trap before mass spectrometry and a time-of-flight (TOF) mass spectrometer section 12 in which ions generated from the sample are directly subjected to mass spectrometry. A mass spectrum creator 21 creates an IT mass spectrum and a TOF mass spectrum from the measured results. A glycopeptide detector 23 detects fragment ion peaks related to neutral loss of sugars from the IT mass spectrum as well as peaks corresponding to intact molecular ions from the TOF mass spectrum, and furthermore, detects peaks common to the two spectra as glycopeptide ions. A quantitative analyzer 24 determines relative quantities of glycoforms of the glycopeptide based on the TOF mass spectrum. A structural analyzer 25 analyzes the structure of the glycopeptide using the result of an MSn analysis of the sample S.

Abstract: A closed electron impact ion source with overall opening area of less than 30 mm2 is employed for direct and pulsed extraction into a time-flight mass spectrometer in order to enhance sensitivity and immunity to chemical noise of oil and fumes of the vacuum system. For compatibility with dual stage GC×GC separation, the source may contain an inert liner surrounded by an isothermal cage of thermally conductive material. The source inner surface may be reduced to under 100 mm2. A portion of carrier gas may be pumped down before admitting the sample and carrier gas into the source. A cooled surface may be used to condense fumes at the analysis time.

Abstract: In an atmospheric pressure ionization source using an ESI or the like having a desolvation pipe with one end opening serving as an ion-drawing port, a drying-gas supplying port for supplying a drying gas against the ion-drawing direction is provided below the ion-drawing port, i.e. at a position opposite to the side where a nozzle for spraying a liquid sample into an atmospheric pressure atmosphere is located, as viewed from the ion-drawing port. When the drying gas is supplied from the drying-gas supplying port, the gas pressure becomes higher in a region above the ion-drawing port becomes higher than in a region below the same port and produces a downward air stream. This stream helps ions in the spray flow from the nozzle to easily come close to the ion-drawing port and be efficiently drawn into the desolvation pipe.

Abstract: A Time of Flight mass analyser is disclosed comprising an annular ion guide having a longitudinal axis and comprising a first annular ion guide section and a second annular ion guide section. Ions are introduced into the first annular ion guide section so that the ions form substantially stable circular orbits within the first annular ion guide section about the longitudinal axis. An ion detector is disposed within the annular ion guide. Ions are orthogonally accelerated in a first axial direction from the first annular ion guide section into the second annular ion guide section. An axial DC potential is maintained along at least a portion of the second annular ion guide section so that the ions are reflected in a second axial direction which is substantially opposed to the first axial direction. The ions undergo multiple axial passes through the second annular ion guide section before being detected by the ion detector.

Abstract: The invention generally relates to systems and methods for mass spectrometry analysis of microorganisms in samples.

Abstract: A method and device for early detection of fires is based on the detection of volatile thermolysis products which are characteristic of the material to be monitored, ambient air being aspirated from an area to be monitored with respect to fire and being ionized, the ionized gas flow being channeled through an electromagnetic field, the resulting field strength of which modifying the trajectories of the ions in their temporal and spatial dependence with a parameter set in such a manner that positive and/or negative ions of the ionized gas are forced onto pre-determined trajectories and are detected for generating a fire alarm. Accordingly, fires can be detected quickly and reliably in the earliest possible phase before their full development so that taking or initiating follow-up actions can occur particularly quickly and at an early stage.

Abstract: A mass spectrometer is disclosed comprising a RF ion guide wherein in a mode of operation a continuous, quasi-continuous or pulsed beam of ions is orthogonally sampled from the ion guide and wherein the continuous, quasi-continuous or pulsed beam of ions is not axially trapped or otherwise axially confined within the RF ion guide. The ion guide is maintained, in use, at a pressure selected from the group consisting of: (i) 0.0001-0.001 mbar; (ii) 0.001-0.01 mbar; (iii) 0.01-0.1 mbar; (iv) 0.1-1 mbar; (v) 1-10 mbar; (vi) 10-100 mbar; and (vii) >100 mbar.

Abstract: A time-of-flight mass spectrometry (TOF MS) system includes an ion deflector, ion extractor, a flight tube, and a detector. The deflector may be disposed in the flight tube or outside the flight tube upstream of the extractor. The deflector deflects ions away from a main flight path such that the defected ions are not detected.

Abstract: Projection TOF mass spectrum distribution information is acquired by irradiating a first ionizing beam onto a surface of a specimen to acquire first mass spectrum distribution information on secondary ions generated from the specimen, irradiating a second ionizing beam onto the same surface to acquire second mass spectrum distribution information on secondary ions generated from the specimen, and correcting the second mass spectrum distribution information on the basis of the first mass spectrum distribution information.

Abstract: Projection TOF mass spectrum distribution information is acquired by irradiating a first ionizing beam onto a surface of a specimen to acquire first mass spectrum distribution information on secondary ions generated from the specimen, irradiating a second ionizing beam onto the same surface to acquire second mass spectrum distribution information on secondary ions generated from the specimen irradiation, and correcting the second mass spectrum distribution information by correcting time-of-flight distribution information of secondary ions in the second mass spectrum distribution information on the basis of detection time distribution of an arbitrary peak in the first mass spectrum distribution information.

Abstract: Apparatus and methods for performing mass spectrometry of a nanoparticle or virus analyte. Apparatus may include a laser desorption plate, a mass analyzer configured to measure mass over the range of m/z from 105 to 1010, an electrical shield surrounding the mass analyzer, and a charge sensitive detector, wherein the laser firing is phase lock synchronized with the applied radiofrequency voltages.

Abstract: A system and method for acquisition of mass spectrometry data is configured to provide a stream of charged particles (e.g., from an analytical volume). A primary mass spectrometer (e.g., time-of-flight mass spectrometer) may be used to separate charged particles of the stream of charged particles based on their mass-to-charge ratio and detect the charged particles in a mass-to-charge spectrum. A stream of precursor ions having a selected mass range may be diverted from the stream of charged particles for fragmentation to provide fragment ions (e.g., fragment ions from the analytical volume). The fragment ions may be provided to a second mass spectrometer for analysis of the fragment ions (e.g., during the same time as the time-of-flight mass spectrometer is separating and detecting charged particles of the stream of charged particles based on their mass-to-charge ratio).

Abstract: A mass spectrometer is disclosed comprising a quadrupole rod set ion trap wherein a potential field is created at the exit of the ion trap which decreases with increasing radius in one radial direction. Ions within the on trap are mass selectively excited in a radial direction. Ions which have been excited in the radial direction experience a potential field which no longer confines the ions axially within the ion trap but which instead acts to extract the ions and hence causes the ions to be ejected axially from the ion trap.

Abstract: A system for performing tandem mass spectrometry (MS/MS) analysis of a sample includes a mass spectrometer and a processor. The mass spectrometer is configured to perform a mass spectrometry (MS) scan of an ionized sample to provide a mass of an observed peak corresponding to a precursor ion. The processor is configured to perform operations including determining whether the mass of the observed peak matches a mass of at least one of multiple expected peptides on a dynamic watch list, where the expected peptides correspond to a protein in the sample, and calculating a score of an accuracy of the determination when the mass of the observed peak is determined to match the mass of at least one of the plurality of expected peptides. The precursor ion is excluded from an MS/MS scan when the accuracy score indicates that the determination is accurate.

Abstract: The present invention relates to a method of mass spectrometry, an apparatus adapted to perform the method and a mass spectrometer. More particularly, but not exclusively, the present invention relates to a method of mass spectrometry comprising the step of associating parent and fragmentation ions from a sample by measuring the parent and fragmentation ions from two or more different areas of the sample and identifying changes in the number of parent ions between the areas in the sample, and corresponding changes in the number of fragmentation ions between the two areas.

Abstract: The present invention is concerned with an ion analysis apparatus comprising an ion guide having an ion optical axis extending from an ion inlet to an ion outlet, the ion guide being configured to guide ions from the ion inlet to the ion outlet along the ion optical axis, wherein the ion guide comprises at least one extraction region located between the ion inlet and the ion outlet, the at least one extraction region being configured to extract ions moving along the ion optical axis of the ion guide in an extraction direction, the extraction direction being substantially orthogonal to the ion optical axis of the ion guide, wherein the apparatus includes ion radial confinement means that in use confine the ions in the radial direction within the ion guide.

Abstract: An orthogonal pulse accelerator for a Time-of-Flight mass analyzer includes an electrically-conductive first plate extending in a first plane, and a second plate spaced from the first plate. The second plate includes a grid that defines a plurality of apertures each having a first dimension extending in a first direction and a second dimension orthogonal to the first dimension, the first and second dimensions lying in the second plane and the second dimension begin larger than the first dimension. The first and second plates are positioned in the Time-of-Flight mass analyzer to receive, during operation of the mass analyzer, an ion beam propagating in the first direction in a region between the first and second plates, and the orthogonal pulse accelerator directs ions in the ion beam through the apertures.

Abstract: LC/MS data generated by an LC/MS system is analyzed to determine groupings of ions associated with originating molecules. Ions are grouped initially according to retention time, for example, using retention time or chromatographic peaks in mass chromatograms. After initial groupings are determined based on retention time, ion peak shapes are compared to determine whether ions should be excluded. Ions having peak shapes not matching other ions, or alternatively a reference peak shape, are excluded from the group.

Abstract: A time-of-flight mass spectrometry (TOF MS) system includes an ion deflector, ion extractor, a flight tube, and a detector. The deflector may be disposed in the flight tube or outside the flight tube upstream of the extractor. The deflector deflects ions away from a main flight path such that the defected ions are not detected.

Abstract: A mass spectrometer is disclosed comprising a time of flight mass analyzer. The time of flight mass analyzer comprises an ion guide comprising a plurality of electrodes which are interconnected by a series of resistors forming a potential divider. Ions are confined radially within the ion guide by the application of a two-phase RF voltage to the electrodes. A single phase additional RF voltage is applied across the potential divider so that an inhomogeneous pseudo-potential force is maintained along the length of the ion guide.

Abstract: In an MS unit, both an intensity of an ion having the highest intensity among the ions originating from a compound as the target of quantitative determination and an intensity of an isotopic ion are measured. A saturation detector determines whether or not digital data produced by an A/D converter from ion-intensity signals have reached a saturation level. A data selection controller selects the ion-intensity data showing the highest intensity when the signal is not saturated or the intensity data of the isotopic ion when the saturation has occurred or is probable to occur. When the latter data is selected, an ion intensity converter converts the intensity data into values corresponding to the intensity data of the highest-intensity ion by multiplying the intensity data by a factor calculated from a known isotopic abundance ratio.

Abstract: An improved trap-TOF mass spectrometer has a set of electrodes arranged to produce both a quadrupolar RF confining field and a substantially homogeneous dipole field. In operation, ions are first confined by the RF field and then, at a selected time, the RF confining field is discontinued and the dipole field is used to accelerate the ions so as to initiate a TOF MS analysis. The apparatus of the present invention may be used alone or in conjunction with other analyzers to produce mass spectra from analyte ions.

Abstract: The present invention provides a timing device, especially a timing device for use in mass spectrometers, for example TOF mass spectrometers, for processing trigger signal data containing a trigger signal indicating the occurrence of a trigger event, the timing device having: a trigger signal deserializer configured to receive trigger signal data containing a trigger signal indicating the occurrence of a trigger event as serial data and to output the trigger signal data as parallel data, and wherein suitably the timing device has a processing means configured to process trigger signal data outputted by the trigger signal deserializer as parallel data.

Abstract: Systems and methods for automatic gain control in mass spectrometers are disclosed. An exemplary system may include a mass spectrometer, comprising a lens configured to receive a supply of ions, and a mass analyzer. The mass analyzer may include an ion trap for trapping the supplied ions. The mass analyzer may also include an ion detector for detecting ions that exit the ion trap. The lens may focus the ions non-uniformly based on mass of the ions to compensate for space charge effects reflected in a measurement output of the mass spectrometer. An exemplary method may include focusing an ion beam into a mass analyzer. The method may also include obtaining a mass spectrum and identifying a space charge characteristic based on the mass spectrum. The method may further include defocusing the lens based on the identified space charge characteristic, wherein defocusing the lens is configured to divert lighter ions away from the entrance aperture.

Abstract: When a time-of-flight mass selector having a chopper using a deflector selects the masses of the ions, an ion beam is deflected. As a result, at least a part of the ion beams diagonally pass through an aperture electrode with respect to the axis. Accordingly, there has been a problem that a position on an object irradiated with a cluster ion beam, results in moving. This mass selector includes: a flight tube having an equipotential space that makes a charged substance fly therein; a deflector that is installed in a downstream side with respect to the flight tube in a direction in which the charged substance flies; a first aperture electrode that is installed in a downstream side with respect to the deflector in a direction in which the charged substance flies; and a second aperture electrode that is installed in between the deflector and the first aperture electrode.

Abstract: The invention generally relates to systems and methods for transferring ions for analysis. In certain embodiments, the invention provides a system for analyzing a sample including an ionizing source for converting molecules of a sample into gas phase ions in a region at about atmospheric pressure, an ion analysis device, and an ion transfer member operably coupled to a gas flow generating device, in which the gas flow generating device produces a laminar gas flow that transfers the gas phase ions through the ion transfer member to an inlet of the ion analysis device.

Abstract: In a mass cytometer or mass spectrometer, a sample of elemental tagged particles is transferred from a dispersion to a gas flow through a carrier aerosol spray for atomization and ionization by inductively coupled plasma (ICP) source. The configuration of the sample transfer apparatus allow for total consumption of the sample by passing the sample spray through a deceleration stage to decelerate the spray of particles from its high velocity expansion. Following the deceleration stage, the decelerated sample of particles can be accelerated and focused through an acceleration stage for transferring into the ICP. This effectively improves the particle transfer between the sample spray and the ICP.

Abstract: An ion accelerator for a time-of-flight mass spectrometer includes a pulsed ion accelerator positioned proximate to a sample plate and having an electrode that is electrically connected to the sample plate. An accelerator power supply generates an accelerating potential on the ion accelerator electrode that accelerates a pulse of ions generated from the sample positioned on the sample plate. An ion focusing electrode is positioned after the pulsed ion accelerator. A potential applied to the ion focusing electrode focuses the pulse of ions into a substantially parallel beam propagating in an ion flight path. A static ion accelerator is positioned proximate to the ion focusing electrode with an input that receives the pulse of ions focused by the ion focusing electrode. The static ion accelerator accelerating the focused pulse of ions.

Abstract: A tandem mass spectrometer and method are described. Precursor ions are generated in an ion source (10) and an ion injector (21, 23) injects ions towards a downstream ion guide (50, 60) via a single or multi reflection TOF device (30) that separates ions into packets in accordance with their m/z. A single pass ion gate (40) in the path of the precursor ions between the ion injector (21, 23) and the ion guide (50, 60) is controlled so that only a subset of precursor ion packets, containing precursor ions of interest, is allowed onward transmission to the ion guide (50, 60). A high resolution mass spectrometer (70) is provided for analysis of those ions, or their fragments, which have been allowed passage through the ion gate (40). The technique permits multiple m/z ranges to be selected from a wise mass range of precursors, with optional fragmentation of one or more of the chosen ion species.

Abstract: A method of mass spectrometry is disclosed wherein the intensity of an analyte is determined by determining the intensity of first characteristic fragment ions when the intensity of the first characteristic fragment ions is within a first intensity range corresponding to the detection or unsaturated range of an ion detector. However, when the intensity of the first characteristic fragment ions is outside of the first intensity range so that the ion detector would saturate then the intensity of the analyte is determined by determining the intensity of second different characteristic fragment ions.

Abstract: A co-axial time-of-flight mass spectrometer having a longitudinal axis and first and second ion mirrors at opposite ends of the longitudinal axis. Ions enter the spectrometer along an input trajectory offset from the longitudinal axis and after one or more passes between the mirrors ions leave along an output trajectory offset from the longitudinal axis for detection by an ion detector. The input and output trajectories are offset from the longitudinal axis by an angle no greater than formula (I): where Dmin is the or the minimum transverse dimension of the ion mirror and L is the distance between the entrances of the ion mirrors.

Abstract: Provided is an ionization apparatus including: a holder configured to hold a sample; a probe configured to determine a part to be ionized of the sample held by the holder; an extract electrode configured to extract ionized ions of the sample; a liquid supply unit configured to supply liquid to a part of a region of the sample; and a unit configured to apply a first voltage between the probe and the extract electrode, in which the first voltage is pulse-modulated.

Abstract: An ion detector for a Time of Flight mass spectrometer is disclosed comprising a single Microchannel Plate which is arranged to receive ions and output electrons. The electrons are directed onto an array of photodiodes which directly detects the electrons. The output from each photodiode is connected to a separate Time to Digital Converter provided on an ASIC.

Abstract: Certain embodiments described herein are directed to reflectron assemblies and methods of producing them. In some configurations, a reflectron comprising a plurality of lenses each comprising a planar body and comprising a plurality of separate and individual conductors spanning a central aperture from a first side to a second side of a first surface of the planar body is described. In some instances, the plurality of conductors are each substantially parallel to each other and are positioned in the same plane.

Abstract: Presented is a mass spectrometer comprising an ion path along which ions are transported between different sections of the mass spectrometer, and further comprising an arrangement with a receptacle being located along the ion path in the mass spectrometer and a complementary mount for carrying a removable ion-optical assembly, such as a carrier of electrodes for a MALDI ion source, wherein the mount can be removed from and reinserted into the receptacle in a plane approximately perpendicular to an ion path axis.

Abstract: A multi-reflection mass spectrometer is provided comprising two ion-optical mirrors, each mirror elongated generally along a drift direction (Y), each mirror opposing the other in an X direction, the X direction being orthogonal to Y, characterized in that the mirrors are not a constant distance from each other in the X direction along at least a portion of their lengths in the drift direction. In use, ions are reflected from one opposing mirror to the other a plurality of times while drifting along the drift direction so as to follow a generally zigzag path within the mass spectrometer. The motion of ions along the drift direction is opposed by an electric field resulting from the non-constant distance of the mirrors from each other along at least a portion of their lengths in the drift direction that causes the ions to reverse their direction.

Abstract: A multi-reflection mass spectrometer comprising two ion-optical mirrors, each mirror elongated generally along a drift direction (Y), each mirror opposing the other in an X direction and having a space therebetween, the X direction being orthogonal to Y; the mass spectrometer further comprising one or more compensation electrodes each electrode being located in or adjacent the space extending between the opposing mirrors; the compensation electrodes being configured and electrically biased in use so as to produce, in at least a portion of the space extending between the mirrors, an electrical potential offset which: (i) varies as a function of the distance along the drift length, and/or; (ii) has a different extent in the X direction as a function of the distance along the drift length. In a preferred embodiment the period of ion oscillation between the mirrors is not substantially constant along the whole of the drift length.

Abstract: A mass spectrometer is disclosed wherein an ion signal is split into a first and second signal. The first and second signals are multiplied by different gains and are digitized. Arrival time and intensity pairs are calculated for both digitized signals and the resulting time and intensity pairs are combined to form a high dynamic range spectrum. The spectrum is then combined with other corresponding spectra to form a summed spectrum.

Abstract: A method and apparatus for tandem mass spectrometry is disclosed. Precursor ions are fragmented and the fragments are accumulated in parallel, by converting an incoming stream of ions from an ion source (10) into a time separated sequence of multiple precursor ions which are then assigned to their own particular channel of a multi compartment collision cell (40). In this manner, precursor ion species, being allocated to their own dedicated fragmentation cell chambers (41, 42 . . . 43) within the fragmentation cell (40), can then be captured and fragmented by that dedicated fragmentation chamber at optimum energy and/or fragmentation conditions.

Abstract: An ion detector system for a mass spectrometer is disclosed comprising an ion detector comprising an array of detector elements. The ion detector system is arranged to correct for tilt and non-linear aberrations in an isochronous plane of ions. The ion detector system generates separate first mass spectral data sets for each detector element and then applies a calibration coefficient to each of the first mass spectral data sets to produce a plurality of second calibrated mass spectral data sets. The plurality of second calibrated mass spectral data sets are then combined to form a composite mass spectral data set.

Abstract: A method, apparatus and algorithms are disclosed for operating an open electrostatic trap (E-trap) or a multi-pass TOF mass spectrometer with an extended flight path. A string of start pulses with non equal time intervals is employed for triggering ion packet injection into the analyzer, a long spectrum is acquired to accept ions from the entire string and a true spectrum is reconstructed by eliminating or accounting overlapping signals at the data analysis stage while using logical analysis of peak groups. The method is particularly useful for tandem mass spectrometry wherein spectra are sparse. The method improves the duty cycle, the dynamic range and the space charge throughput of the analyzer and of the detector, so as the response time of the E-trap analyzer. It allows flight extension without degrading E-trap sensitivity.

Abstract: Certain embodiments described herein are directed to time of flight tubes comprising a cylindrical tube comprising an inner surface and an outer surface, the cylindrical tube comprising an effective thickness and sized and arranged to couple to and support a reflectron assembly inside the cylindrical tube. In some configurations, the cylindrical tube further comprises a conductive material disposed on the inner surface of the cylindrical tube, the conductive material present in an effective amount to provide a field free region for ions when the conductive material is charged.

Abstract: In some embodiments, a time of flight mass spectrometer can comprise an input orifice for receiving ions, a first ion accelerator stage for accelerating the ions along a first path, at least one ion reflector for receiving said accelerated ions and redirecting said ions along a second path different than the first path, a detector for detecting at least a portion of the ions redirected by said at least one ion reflector, and at least first and second field free drift regions disposed between said first acceleration stage and said detector, wherein said second field free region is disposed in proximity of the detector. In some embodiments, the lengths of the field free drift regions can be selected so as to provide 1st and 2nd order corrections of the time of flight of the ions with respect to variation in their initial positions.

Abstract: The invention generally relates to systems and methods for transferring ions for analysis. In certain embodiments, the invention provides a system for analyzing a sample including an ionizing source for converting molecules of a sample into gas phase ions in a region at about atmospheric pressure, an ion analysis device, and an ion transfer member operably coupled to a gas flow generating device, in which the gas flow generating device produces a laminar gas flow that transfers the gas phase ions through the ion transfer member to an inlet of the ion analysis device.

Abstract: In one aspect of the invention, an ion trap mass analyzer includes a variable- or multi-potential type ion guide (MPIG) assembly which has been pre-configured to produce a parabolic-type potential field. Each MPIG electrode has a resistive coating of designed characteristics. In one example the coating varies in thickness long the length of an underlying uniform substrate. The MPIG assembly can be a single MPIG electrode or an array of a plurality of MPIG electrodes. An array can facilitate delocalization for improved performance. This chemical modification of a uniform underlying substrate promotes cheaper and flexible instruments. The modified MPIG electrodes also allow miniaturization (e.g. micro and perhaps even nano-scale), which allows miniaturization of the instrument in which the single or plural modified MPIG electrode(s) are placed. This promotes portability and field use instead of limitation to laboratory settings.

Abstract: A method is provided for calibrating mass-to-charge ratio measurements obtained from a time-of-flight mass spectrometer used as a detector for a chromatographic system. The method can include introducing a calibrant material into the time-of-flight mass spectrometer after a sample is introduced to the chromatographic system, but before the analysis of the sample is complete, such that calibrant material and sample material are not present at the ion source of the mass spectrometer, contemporaneously, and back-flushing residual or leaking calibrant through a back-flush line and away from the mass spectrometer.

Abstract: Methods are provided for acquiring sum spectra in a time-of-flight mass spectrometer with orthogonal pulsed acceleration, where each of the sum spectra is obtained from a plurality of summed individual spectra. The mass spectrometer has an ion storage device that collects the ions temporarily before they are transferred to an ion pulser, which pulses out the ions orthogonally. Acquisition conditions such as, for example, delay times between opening the ion storage device and the pulsed ejection in the ion pulser are varied for the individual spectra, which are added together to form the sum spectrum of ions with light masses and high masses.

Abstract: The present invention relates to inductively coupled plasma mass spectrometry (ICPMS) in which a collision cell is employed to selectively remove unwanted artefact ions from an ion beam by causing them to interact with a reagent gas. The present invention provides a first evacuated chamber (6) at high vacuum located between an expansion chamber (3) and a second evacuated chamber (20) containing the collision cell (24). The first evacuated chamber (6) includes a first ion optical device (17). The collision cell (24) contains a second ion optical device (25). The provision of the first evacuated chamber (5) reduces the gas load on the collision cell (24), by minimising the residual pressure within the collision cell (24) that is attributable to the gas load from the plasma source (1). This serves to minimise the formation, or re-formation, of unwanted artefact ions in the collision cell (24).