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 collision or fragmentation cell is disclosed comprising a plurality of electrodes wherein a first RF voltage is applied to an upstream group of electrodes and a second different RF voltage is applied to a downstream group of electrodes. The radial confinement of parent ions entering the collision or fragmentation cell is optimised by the first RF voltage applied to the upstream group of electrodes and the radial confinement of daughter or fragment ions produced within the collision or fragmentation cell is optimised by the second different RF voltage applied to the downstream group of electrodes.

Abstract: Provided are a controller and a control method for improving signal performance of an ion cyclotron resonance mass spectrometer. The controller and control method apply electric signals for causing ions injected into an ion trap of the ion cyclotron resonance mass spectrometer to be injected to the center of the trap as close as possible to trap electrodes, and adjust biased ion motion by appropriately adjusting signals of trap electrodes for causing the injected ions to make ion motion, thereby improving the fidelity of ion signals. The control method for improving signal performance of an ion cyclotron resonance mass spectrometer includes an ion position adjustment process and an ion signal detection process.

Abstract: An ion mobility separator or spectrometer is disclosed comprising an inner cylinder and an outer cylinder defining an annular volume through which ions are transmitted. Spiral electrodes a-f are arranged on a surface of the inner cylinder and/or on a surface of the outer cylinder. A first device is arranged and adapted to maintain a DC electric field or a pseudo-potential force which acts to urge ions from a first end of the ion mobility separator or spectrometer to a second end of the ion mobility separator or spectrometer. A second device is arranged and adapted to apply one or more transient DC voltages to the spiral electrodes in order to urge ions towards the first end of the ion mobility separator or spectrometer. The net effect is to extend the effective path length of the ion mobility separator.

Abstract: An electrostatic trap such as an orbitrap is disclosed, with an electrode structure. An electrostatic trapping field of the form U? (r, ?, z) is generated to trap ions within the trap so that they undergo isochronous oscillations. The trapping field U?(r, ?, z) is the result of a perturbation W to an ideal field U(r, ?, z) which, for example, is hypologarithmic in the case of an orbitrap. The perturbation W may be introduced in various ways, such as by distorting the geometry of the trap so that it no longer follows an equipotential of the ideal field U(r, ?, z), or by adding a distortion field (either electric or magnetic). The magnitude of the perturbation is such that at least some of the trapped ions have an absolute phase spread of more than zero but less than 2 ? radians over an ion detection period Tm.

Abstract: The present invention relates to a method of improving detection sensitivity of an ion mobility spectrometer, comprising: inserting a sample into a sample receiving device of the ion mobility spectrometer; triggering an operation of spectra acquisition through an optocoupler; when the number of the acquired spectra reaches the level required to contain enough information for accurate detection of explosives with relatively high vapor pressure, adding a dopant instantly to the ionization region by controlling the ON/OFF-state of an electromagnetic valve; when the number of the acquired spectra reaches the level required to contain enough information for accurate detection of explosives with relatively low vapor pressure, stopping the acquisition operation, and turning off the electromagnetic valve so as to stop adding the dopant to the ionization region; analyzing all of the acquired spectra to obtain the detection result.

Abstract: A mass spectrometry method that corrects the effects from space charge and that achieves both sensitivity and a dynamic range. The mass axis of the mass spectrum is corrected based on the counts of ions accumulated within the ion trap at the point in time each ion was extracted.

Abstract: A mass spectrometer is disclosed wherein highly charged fragment ions resulting from Electron Transfer Dissociation fragmentation of parent ions are reduced in charge state within a Proton Transfer Reaction cell by reacting the fragment ions with a neutral superbase reagent gas such as Octahydropyrimidolazepine.

Abstract: In an ion cyclotron resonance cell, which is enclosed at its ends by electrode structure elements with DC voltages of alternating polarity, longitudinal electrodes are divided so that the ICR measurement cell between the electrode structure elements consists of at least three sections. An excitation of ion cyclotron motions can be performed by applying additional trapping voltages to longitudinal electrodes located closest to the electrode structure elements and introducing ions into the center set of longitudinal electrodes. The ions are then excited into cyclotron orbits by applying radiofrequency excitation pulses to at least two rows of longitudinal electrodes to produce orbiting ion clouds. Subsequently, the additional trapping voltages are removed and an ion-attracting DC voltage is superimposed on the DC voltages. Ions excited to circular orbits can be detected using detection electrodes in the outer ICR cell sections.

Abstract: An ion trap for a mass spectrometer has a conductive central electrode with an aperture extending from a first open end to a second open end. A conductive first electrode end cap is disposed proximate to the first open end thereby forming a first intrinsic capacitance between the first end cap and the central electrode. A conductive second electrode end cap is disposed proximate to the second open end thereby forming a second intrinsic capacitance between the second end cap and the central electrode. A first circuit couples the second end cap to a reference potential. A signal source generating an AC trap signal is coupled to the central electrode. An excitation signal is impressed on the second end cap in response to a voltage division of the trap signal by the first intrinsic capacitance and the first circuit.

Abstract: Devices and methods for the acquisition of mass spectra with very high mass resolution in ion cyclotron resonance mass spectrometers include cylindrical ICR measuring cells with special electrode geometries to generate harmonic trapping potentials for orbiting ions. The sheath of the cylindrical cell is divided by longitudinal gaps into a multitude of sheath electrodes, which either have to carry layers with resistance profiles able to generate parabolic voltage profiles along the sheath electrodes, or which form sheath electrodes of varying width by parabolic gaps. Orbiting ions of a given mass m/z oscillate harmonically in an axial direction with the same frequency, independent of the radius of their orbit and their oscillation amplitude. Ideally, the cylinders are closed by endcaps with rotationally hyperbolic form, divided into partial electrodes. The ions are excited by dipolar excitation fields. The orbiting ion clouds are kept together for much longer periods than was possible hitherto.

Abstract: Apparatus and methods are provided that enable the interaction of low energy electrons and positrons with sample ions to facilitate electron capture dissociation (EGO) and positron capture dissociation (PGO), respectively, within multipole ion guide structures. The apparatus and methods described herein allow EGO (and PCO) to be performed within multipole ion guides, either alone, or in combination with conventional ion fragmentation methods.

Abstract: This invention relates to mass spectrometry that includes ion trapping in at least one of the stages of mass analysis. In particular, although not exclusively, this invention relates to tandem mass spectrometry where precursor ions and fragment ions are analyzed. A method of mass spectrometry is provided comprising the sequential steps of: accumulating in an ion store a sample of one type of ions to be analyzed; accumulating in the ion store a sample of another type of ions to be analyzed; and mass analyzing the combined samples of the ions; wherein the method comprises accumulating the sample of the one type of ions and/or the sample of another type of ions to achieve a target number of ions based on the results of a previous measurement of the respective type of ions.

Abstract: Ion guides for use in mass spectrometry (MS) systems are described. The ion guides are configured to provide a reflective electrodynamic field and a direct current (DC or static) electric field to provide ion beams that are more spatially confined with a comparatively large mass range. Some ion guides are provided between the ion source and the first stage vacuum chamber of the MS system.

Abstract: A mass spectrometer having a resolution improved by introducing ions into a mass spectrometry part with a high efficiency is provided with a small-sized, simple configuration. The mass spectrometer includes an opening/closing mechanism provided between a sample introducing piping part for introducing a sample into the mass spectrometry part and the mass spectrometry part to conduct gas introduction intermittently and control sample passage. The mass spectrometer further includes a pump mechanism to evacuate a high pressure side of the sample introducing piping part, that is, an opposite side of the opening/closing mechanism to the mass spectrometry part to have a pressure in a range of 100 to 10,000 Pa.

Abstract: A mass spectrometric device of the present invention includes a quadrupole filter (12) located upstream of a quadrupole ion trap (13) and configured to transmit ions in a predetermined filter range, and determines the filter range of the quadrupole filter (12) such that accumulation time for the ions in the quadrupole ion trap (13) is maximized. The accumulation time for the ions is determined based on mass spectrometry data information. With this configuration, the present invention produces advantageous effects of improving analysis throughput and an S/N ratio in an analysis of a minor sample component mixed in various accompanying components by using the mass spectrometric device using the quadrupole ion trap.

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 object of the present invention is to provide means for solving troubles. Examples of the troubles include sensitivity degradation and resolution degradation of a mass spectrometer, which are caused by an axis deviation of a component, particularly at least one orifice located between an ion source and a detector, to decrease the number of ions reaching the detector, and a variation in performance caused by exchange of components such as the orifice. For example, the invention has the following configuration in order to solve the troubles. A mass spectrometer includes: an ion source; a detector that detects an ion; an orifice and a mass separator that are disposed between the ion source and the detector; and an axis adjusting mechanism that adjusts axis positions of the orifice and/or the mass separator such that an opening of the orifice and/or an incident port of the mass separator is disposed on a line connecting the ion source and an incident port of the detector.

Abstract: Provided are methods for determining the amount of reverse T3 in a sample using mass spectrometry. The methods generally involve ionizing reverse T3 in a sample and detecting and quantifying the amount of the ion to determine the amount of reverse T3 in the sample.

Abstract: A method of processing a plurality of image charge/current signals representative of trapped ions undergoing oscillatory motion, e.g. for use in an ion trap mass spectrometer. The method includes producing a linear combination of the plurality of image charge/current signals using a plurality of predetermined coefficients, the predetermined coefficients having been selected so as to suppress at least one harmonic component of the image charge/current signals within the linear combination of the plurality of image charge/current signals.

Abstract: A High Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) apparatus comprises (a) a first and a second gas inlet; (b) an expansion chamber receiving ions from an ion source and the first and second gas flows from the first and second gas inlets, respectively; (c) an outer electrode having a generally concave inner surface and comprising: (i) an ion inlet operable to receive, from the expansion chamber, the ions and a combined gas flow comprising portions of the first and second gas flows; and (ii) an ion outlet; and (d) an inner electrode having a generally convex outer surface that is disposed in a spaced-apart and facing arrangement relative to the inner surface of the outer electrode for defining an ion separation region therebetween, wherein the combined gas flow and a portion of the ions travel through the ion separation region from the ion inlet to the ion outlet.

Abstract: In one embodiment, a mass spectrometer includes an RF drive circuit for generating RF signals, a quadrupole mass filter, and a fixed connection assembly for delivering RF signals from the RF drive circuit to the quadrupole mass filter, the fixed connection assembly representing the entire delivery path of RF signals from the RF drive circuit to the quadrupole mass filter. By avoiding flexible components such as a freestanding wires or flexible circuit boards, the need for retuning when parts are removed or disturbed for testing or servicing is reduced, and a modular instrument in which components and connections are standardized and therefore interchangeable is realized.

Abstract: One virtual rod electrode (11) is composed by arraying a plurality of plate electrodes (111, . . . , 118) along an ion beam axis, and a quadrupole ion optical element (1) is constructed by arranging four virtual rod electrodes (11, 12, 13 and 14) around an ion beam axis C. A voltage-applying unit alternately applies two radio-frequency voltages having a phase difference of 180 degrees for each of the plate electrodes in one virtual rod electrode. By this voltage application, the quadrupole component of the radio-frequency electric field created within a space surrounded by the four virtual rod electrodes is decreased, while higher-order multipole components are increased. The quadrupole component yields high ion convergence and mass selectivity, while the higher-order components provide high ion transmission efficiency and ion acceptance.

Abstract: An ion mobility tube comprises an ionization source chamber having a center ionization source chamber hole, an ion door, a mobility region unit having a center mobility tube chamber, a constraining grid, and a Faraday disk, and the ionization source chamber, the ion door, the mobility region unit, the constraining grid, and the Faraday disk are laminated together in sequence in a front-rear direction, wherein the mobility region unit comprises a first insulator and first metal electrode sheets concentrically fixed to a front surface and a back surface of the first insulator respectively. The mobility region unit comprises the first insulator and the first metal electrode sheets which are integral. Therefore, the ion mobility tube is advantageous in simplified manufacturing, and convenient for detachment and assembly.

Abstract: In order to provide an analysis method that is capable of determining a glycan structure with high detection sensitivity, a method of the present invention includes the steps of: carrying out triple quadrupole mass spectrometry at various values of CID energy; creating an energy-resolved profile including yield curves representing relationships between (i) a value of the CID energy and (ii) measured amounts of specific types of product ions; preparing a reference profile, and identifying a glycan structure of a test material by comparing the energy-resolved profile with the reference profile.

Abstract: When an SIM measurement for ions originating from a target component separated by a chromatograph is performed, the measurement is performed while the mass-resolving power is switched among a plurality of levels of resolving power, with the mass-to-charge ratio fixed at a target value (S2), and an extracted ion chromatogram is created based on each of data obtained corresponding to respective mass-resolving powers (S3). After the extracted ion chromatograms are obtained, an S/N ratio is calculated for a peak of the target component on each of the chromatograms (S4), and a mass-resolving power which yields the highest S/N ratio is selected (S5). The selected mass-resolving power is set as the mass-resolving power in the subsequent measurements of the same target component in the same kind of sample (S6), and the quantitative determination of the target component is performed using the extracted ion chromatogram obtained with the selected mass-resolving power (S7).

Abstract: The invention relates to devices for measuring the mobility of ions in gases at pressures of a few hectopascal. To make the device more compact, drift regions are bent into curved shapes, which extend into the third dimension. Parts of the drift region may lie above others. Alternating directions of curvature in the curved shapes balance out different path lengths by passing through approximately equal drift distances on outer and inner trajectories. Ions are held near the axis of the curved drift region by sectional or permanent focusing. One possible shape is a double loop in the shape of a figure eight. The shape extends perpendicular to its plane of projection so that several double loops lie on top of each other. RF ion funnels or ion tunnels can keep the ions near the axis. Axial focusing may use a pseudopotential radial to the axis of the curved shape.

Abstract: In an ion cyclotron resonance mass spectrometer ions are excited into cyclotron orbits by an alternating current excitation signal having a nonlinear function of the excitation frequency vs. time in a “chirp.” Such an excitation signal produces transients which have no pronounced beats, even if mixtures of many ion species, all having the same mass differences, are present. The dynamic measuring range for the image currents can thus be better utilized. In particular, sum spectra of specified quality can be generated from a significantly smaller number of individual transients, and thus in a significantly shorter measuring time.

Abstract: A mass spectrum is acquired by accumulating parent ions in an ion trap, ejecting parent ions of a selected m/z ratio into a collision cell, producing fragment ions from the parent ions, and analyzing the fragment ions in a mass analyzer. The other parent ions remain stored in the ion trap, and thus the process may be repeated by mass-selectively scanning parent ions from the ion trap. In this manner, the full mass range of parent ions or any desired subset of the full mass range may be analyzed without significant ion loss or undue time expenditure. The collision cell may provide a large ion acceptance aperture and relatively smaller ion emission aperture. The collision cell may pulse ions out to the mass analyzer. The mass analyzer may be a time-of-flight analyzer. The timing of pulsing of ions out from the collision cell may be matched with the timing of pulsing of ions into the time-of-flight analyzer.

Abstract: A combination of electrodes that are cylindrical and an asymmetric arrangement of cylindrical and planar electrodes are used to create electric fields that compensate for toroidal curvature in a toroidal ion trap, the design lending itself to high precision manufacturing and miniaturization, converging ion paths that enhance detection, higher pressure operation, and optimization of the shape of the electric fields by careful arrangement of the electrodes.

Abstract: A mass spectrometer is disclosed comprising a device which is operable in a first mode of operation to separate ions temporally according to their ion mobility by applying a continuous axial electric field. The device is also operable in a second mode of operation wherein ions are separated temporally according to the their mass to charge ratio by pulsing an applied axial electric field ON and OFF.

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 ion 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 device for use in a mass spectrometer allows an ion-optical assembly to be removed, cleaned and reinserted with relatively high positioning accuracy. In particular, the device obviates the need for complex adjustments requiring special knowledge after the reinsertion. The objective is achieved by an arrangement comprising a receptacle and a mount for a removable ion-optical assembly in a mass spectrometer. Favorable implementations provide a mount and a receptacle with three pairs of complementary support elements, the three support elements on the receptacle form a support plane, and, when the mount is inserted into the receptacle, at least two pairs of support elements are engaged and the mount is aligned with respect to the support plane with the aid of the third pair of support elements.

Abstract: An ion trap comprises a ring electrode and opposite first and second endcap electrodes situated at opposite ends of the ring electrode. A waveform generator is configured to vary both frequency and amplitude of an AC waveform applied across the first and second endcap electrodes as a function of time, thereby exciting ions with a band of resonant secular frequencies substantially without exciting ions with adjacent secular frequencies.

Abstract: A mass spectrum is acquired by accumulating parent ions in an ion trap, ejecting parent ions of a selected m/z ratio into a collision cell, producing fragment ions from the parent ions, and analyzing the fragment ions in a mass analyzer. The other parent ions remain stored in the ion trap, and thus the process may be repeated by mass-selectively scanning parent ions from the ion trap. In this manner, the full mass range of parent ions or any desired subset of the full mass range may be analyzed without significant ion loss or undue time expenditure. The collision cell may provide a large ion acceptance aperture and relatively smaller ion emission aperture. The collision cell may pulse ions out to the mass analyzer. The mass analyzer may be a time-of-flight analyzer. The timing of pulsing of ions out from the collision cell may be matched with the timing of pulsing of ions into the time-of-flight analyzer.

Abstract: Methods and analysers useful for time of flight mass spectrometry are provided.

Abstract: An ion trap includes a containment region for containing ions, and a plurality of electrodes positioned on a regular polyhedral structure encompassing the containment region. An electrode is positioned on each vertex of the encompassing structure and at least one of the polygonal surfaces includes additional electrodes configured to form a plurality of quadrupoles on the surface. Alternating RF voltage is applied to the plurality of electrodes, so that directly neighboring electrodes are of equal amplitude and opposite polarity at any point in time. This configuration on the polyhedral structure forms a potential barrier for repelling the ions from each of the regular polygonal surfaces and containing them in the trap. Mass selective filters can be formed from the quadrupoles for parallel mass analysis in different m/z windows. Application of a small DC potential to a plate electrode outside the quadrupoles preferentially depletes single charged ions for enhanced signal-to-noise analysis.

Abstract: A collision or fragmentation cell is disclosed comprising a plurality of electrodes wherein a first RF voltage is applied to an upstream group of electrodes and a second different RF voltage is applied to a downstream group of electrodes. The radial confinement of parent ions entering the collision or fragmentation cell is optimized by the first RF voltage applied to the upstream group of electrodes and the radial confinement of daughter or fragment ions produced within the collision or fragmentation cell is optimized by the second different RF voltage applied to the downstream group of electrodes.

Abstract: The invention proposes a method for the collective ejection of ions from a 3D RF ion trap with a ring electrode and two end cap electrodes, which comprises the following steps: (a) the RF voltage of a high-quality resonant circuit applied to the ring electrode is replaced with a second RF voltage at the two end cap electrodes which can be changed or switched faster than the high voltage at the ring electrode, keeping the ions stored, (b) the second RF voltage at the end cap electrodes is then switched down or off abruptly, releasing the ions, and (c) the released ions are ejected through an opening in one of the end cap electrodes by switching on a DC voltage on at least one of the end cap electrodes.

Abstract: An ion trap for a mass spectrometer is disclosed. The ion trap includes a ring electrode and first and second electrodes which are arranged on opposite sides of the ring electrode. The ring electrode and the first and second electrodes are configured to generate an electric field based on the received RF signal. The first electrode defines a first aperture and the second electrode defines a second aperture, the first aperture and the second aperture being asymmetric relative to each other and configured to generate a hexapole field.

Abstract: An inductively coupled plasma MS/MS mass analyzer (ICP-MS/MS) may include a first vacuum chamber which draws plasma containing an ionized sample into vacuum, a second vacuum chamber which includes a device or means which extracts and guides ions as an ion beam from the ions output from the first vacuum chamber, a third vacuum chamber which has a first ion optical separation device or means, a fourth vacuum chamber which has a cell into which reaction gas is introduced, and a fifth vacuum chamber which has a second optical separation device or means and a detector, wherein the second vacuum chamber and third vacuum chamber are individually evacuated.

Abstract: A novel method and mass spectrometer apparatus is introduced to enable the simultaneous isolation of cations and anions (i.e., precursor and reagent ions) in a linear multipole ion trap via the application of an additional axial DC gradient in combination with coupled RF potential(s). Thus, the combination of the RF and DC voltages in such an arrangement forms a pseudopotential designed to provide for minima for the trapped positively and negatively charged particles that result in the overlap of the ion clouds so as to provide for beneficial ion/ion reactions.

Abstract: The present invention relates to the analytical electronics used to identify compositions and structures of substances, in particular, to the analyzers comprising at least one mass-spectrometer (MS) and may be applied in such fields as medicine, biology, gas and oil industry, metallurgy, energy, geochemistry, hydrology, ecology. Technical result provides the increase in MS resolution, gain in sensitivity, precision and measurement rates of substances compositions and structures concurrently with enhancement of analyzer functional capabilities, downsizing and mass reduction. In claimed invention the ion flux generation and its guiding are performed in off-axis single-flow mode; parallel multi-stage mode; through use of three-dimensional field with mean meridian surface including without limitation three-dimensional reflecting and dual-zoned reflecting modes or by method of multi-reflection arrays. Devices to implement the claimed method are embodied.

Abstract: A quadrupole power source which applies a voltage to each electrode (2a-2d) of a quadrupole mass filter (2) receives inputs of an m/z-axis correction coefficient Mcomp1 and a V-voltage correction coefficient Vcomp1 in addition to a power supply controlling voltage Qcont according to the m/z of a target ion. Vcomp1 is a reciprocal of the ratio by which a frequency is changed, while Mcomp1 is the square of the ratio by which the frequency is changed. In a detection gain adjuster section (4C), a multiplier (421) multiplies an output Vdet? of a V-voltage adjusting amplifier (405) by Vcomp1, whereby the radio-frequency voltage produced by a radio-frequency power supply section (4A) is maintained at the same level even when the set frequency of a signal generator (411) is changed in order to tune an LC resonance circuit.

Abstract: The present disclosure relates to mass spectrometers and, in particular, multipole ion guides and control units that set the RF and DC potentials at the ion guide to, among other uses, radially confine an ion beam. In an exemplary embodiment, the ion guide includes a plurality of circumferentially arranged elongated rods disposed about a common axis that form a plurality of longitudinally traversing segments. At least a first and a second subset of the segments have an equal number of elongated rods and are physically configured to receive a first and a second set of EMF from a control unit that results in a first multipolar field order distribution and a second multipolar field distribution, respectively, being produced that are different from one another.

Abstract: An ion guide or mass analyzer is disclosed comprising a plurality of electrodes having apertures through which ions are transmitted in use. A pseudo-potential barrier is created at the exit of the ion guide or mass analyzer. The amplitude or depth of the pseudo-potential barrier is inversely proportional to the mass to charge ratio of an ion. One or more transient DC voltages are applied to the electrodes of the ion guide or mass analyzer in order to urge ions along the length of the ion guides or mass analyzer. The amplitude of the transient DC voltage applied to the electrode may be increased with time so that ions are caused to be emitted from the ion guide or mass analyzer in reverse order of their mass to charge ratio.

Abstract: A microengineered multipole ion guide for use in miniature mass spectrometer systems is described. Exemplary methods of mounting rods in hexapole, octupole, and other multipole geometries are described. The rods forming the ion guide are supported by etched silicon structures provided on first and second substrates.

Abstract: A tandem mass spectrometer system and method are described, where a composite voltage waveform is applied to so as to trap ion having selected m/z. The trapped ions may be subject to collision induced ionization dissociation (CID) by a selectable discrete frequency voltage waveform positioned so as to be in a notch in a broadband waveform. The resultant ion products may be trapped using a second notch having a center frequency corresponding to the ion product to be trapped. The process may be repeated so as to increase the amount of ions produced, or the process a first resultant ion product to yield a second resultant in product, which may be trapped.

Abstract: The present invention provides a radio frequency (RF) power supply in a mass spectrometer. The power supply provides an RF signal to electrodes of a storage device to create a trapping field. The RF field is usually collapsed prior to ion ejection. In an illustrative embodiment the RF power supply includes a RF signal supply; a coil arranged to receive the signal provided by the RF signal supply and to provide an output RF signal for supply to electrodes of an ion storage device; and a shunt including a switch operative to switch between a first open position and a second closed position in which the shunt shorts the coil output.

Abstract: Provided is a quadrupole mass spectrometer including direct-current voltage sources having response characteristics which ensure that the response time of the direct-current voltage will be shorter than the period of time required for an ion having the highest mass-to-charge ratio (m/z) among the ions introduced into a quadrupole mass filter to pass through this filter. Main rod electrodes and pre-rod electrodes are connected to each other via primary differentiation circuits. Thus, in the transient state of the voltage change due to the switching of the mass-to-charge ratio, among the ions entering the quadrupole mass filter, ions having low m/z values can be removed by a pre-electrode unit, and ions having high m/z values can be removed by a main electrode unit. Accordingly, a large amount of ions can be prevented from passing through the filter and entering an ion detector.