Abstract: A method of ion mobility spectrometry comprising: (i) introducing a packet of ions into a drift space; (ii) passing the ions through the drift space wherein the ions separate according to their ion mobility; and (iii) reflecting or deflecting the ions that have passed through the drift space back into the drift space wherein the ions can further separate according to their ion mobility. The reflecting or deflecting takes place in a region at lower pressure than the drift space. The drift space may be re-used multiple times to extend the separation path length. The regions of low pressure preferably allow inertial ion motion wherein the mean free path between ion collisions with gas is significantly longer than in the stages of ion mobility separation. The low pressure reflecting or deflecting region enables a time of flight focusing of ions to be provided without ion mobility separation occurring therein.

Abstract: A method of performing imaging mass spectrometry of a sample. The method comprises performing a first mass analysis of the sample using a first mass analyzer comprising a multi-pixel ion detector to obtain first mass spectral data representative of pixels of the sample. The method further comprises identifying clusters of pixels sharing one or more characteristics of first mass spectral data. The method also comprises performing a second mass analysis of the sample using a second mass analyzer to obtain second mass spectral data at at least one location in each cluster, wherein the number of locations is significantly less than the number of pixels in each cluster, said second mass analysis being of higher resolution than said first mass analysis. Also a mass spectrometry apparatus configured for carrying out the method.

Abstract: A tandem mass spectrometer and method are described. Precursor ions are generated in an ion source and an ion injector injects ions towards a downstream ion guide via a single or multi reflection TOF device that separates ions into packets in accordance with their m/z. A single pass ion page in the path of the precursor ions between the ion injector and the ion guide is controlled so that (only a subset of precursor ion packets, containing precursor ions of interest, is allowed onward transmission to the ion guide. A high resolution mass spectrometer is provided for analysis of those ions, or their fragments, which have been allowed passage through the ion gate. 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 selecting ions of interest from a beam of ions using an analyzer, the method comprising: (i) providing an analyzer comprising two opposing ion mirrors each mirror comprising inner and outer field-defining electrode systems elongated along an analyzer axis z, each system comprising one or more electrodes, the outer system surrounding the inner; (ii) causing the beam of ions to fly through the analyzer along a main flight path in the presence of an analyzer field so as to undergo within the analyzer at least one full oscillation in the direction of the analyzer axis while orbiting about or oscillating between one or more electrodes of the inner field defining electrode system; (iii) providing one or more sets of electrodes adjacent the main flight path; (iv) constraining the arcuate divergence from the main flight path of ions of interest by applying one set of voltages to one or more of the sets of electrodes adjacent the main flight path when the ions of interest are in the vicinity of at least on

Abstract: A method of reflecting ions in a multireflection time of flight mass spectrometer is disclosed. The method includes guiding ions toward an ion mirror having multiple electrodes, and applying a voltage to the ion mirror electrodes to create an electric field that causes the mean trajectory of the ions to intersect a plane of symmetry of the ion mirror and to exit the ion mirror, wherein the ion are spatially focussed by the mirror to a first location and temporally focused to a second location different from the first location. Apparatus for carrying out the method is also disclosed.

Abstract: Ions provided from an ion source are separated ions into a plurality of different ion groups according to at least one ion property. At least some of the different ion groups are stored in an ion storage array, which comprises a plurality of independently operable storage cells, each storage cell being arranged to receive and store a different ion group. A controller is programmed to cause selective switching of each of the storage cells between an ion receiving mode and an ion storage mode, and between the ion storage mode and an ion release mode. In particular, the switching of each storage cell is controllable independently of the switching of any of the other storage cells. Upon release from a respective storage cell of the array, ions are provided to one or more mass analyzers for subsequent analysis.

Abstract: A system and method of mass spectrometry is provided. Ions from an ion source are stored in a first ion storage device and in a second ion storage device. Ions are ejected from the first ion storage device to a first mass analysis device during a first ejection time period, for analysis during a first analysis time period. Ions are ejected from the second ion storage device to a second mass analysis device during a second ejection time period. The ion storage devices are connected in series such that an ion transport aperture of the first ion storage device is in communication with an ion transport aperture of the second ion storage device. The first analysis time period and the second ejection time period at least partly overlap.

Abstract: A method of switching between two modes of power supply to a mass analyser is provided. In a first mode of operation, operated for a first predefined time duration, a first power supply, coupled to the mass analyser, generates a first non-zero potential, whilst a second power supply, disconnected from the mass analyser, generates a second non-zero potential. In a second mode of operation, operated for a second predefined time duration, the second potential is coupled to the mass analyser, whilst the first power supply, disconnected from the mass analyser, generates the first potential. These predefined time durations are selected such that only one of: the first potential; and the second potential is coupled to the mass analyser at any time, and such that the first and second modes of operation are carried out at least once within a predetermined length of time.

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: The invention provides a method and apparatus for improving throughput in spectrometry, the method comprising the steps of loading sample-containing liquid into a liquid injection device through a first outlet in the injection device, and ejecting at least some of the sample-containing liquid from the liquid injection device either in the form of droplets or in the form of a jet which subsequently breaks up into droplets due to instability; characterized by the sample ejection being through the first outlet of the liquid injection device in a direction such that the sample-containing fluid enters an inlet of a torch.

Abstract: A method of operating a gas-filled collision cell in a mass spectrometer is provided. The collision cell has a longitudinal axis. Ions are caused to enter the collision cell. A trapping field is generated within the collision cell so as to trap the ions within a trapping volume of the collision cell, the trapping volume being defined by the trapping field and extending along the longitudinal axis. Trapped ions are processed in the collision cell and a DC potential gradient is provided, using an electrode arrangement, resulting in a non-zero electric field at all points along the axial length of the trapping volume so as to cause processed ions to exit the collision cell. The electric field along the axial length of the trapping volume has a standard deviation that is no greater than its mean value.

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 hyperlogarithmic 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: An ion guide for mass spectrometry comprising an electrode arrangement of at least two electrodes, at least one of which is an RF electrode, arranged adjacent to each other but spaced apart on a planar surface of a dielectric material and arranged at a distance from an ion flow path, wherein a portion of the dielectric surface is exposed between an adjacent pair of the spaced apart electrodes and wherein at least one electrode of said adjacent pair of electrodes is arranged to overhang the exposed portion of surface between them such that there is no direct line of sight from the ion flow path to the exposed portion of dielectric surface. The device enables RF guiding of ions accompanied by much reduced charging-up of dielectric surfaces and reduced amount of collisions of neutral species with electrodes.

Abstract: A tandem mass spectrometer and method are described. Precursor ions are generated in an ion source and an ion injector injects ions towards a downstream ion guide via a single or multi reflection TOF device that separates ions into packets in accordance with their m/z. A single pass ion page in the path of the precursor ions between the ion injector and the ion guide is controlled so that (only a subset of precursor ion packets, containing precursor ions of interest, is allowed onward transmission to the ion guide. A high resolution mass spectrometer is provided for analysis of those ions, or their fragments, which have been allowed passage through the ion gate. 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: 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: A method of reflecting ions in a multireflection time of flight mass spectrometer is disclosed. The method includes guiding ions toward an ion mirror having multiple electrodes, and applying a voltage to the ion mirror electrodes to create an electric field that causes the mean trajectory of the ions to intersect a plane of symmetry of the ion mirror and to exit the ion mirror, wherein the ion are spatially focussed by the mirror to a first location and temporally focused to a second location different from the first location. Apparatus for carrying out the method is also disclosed.

Abstract: A method of operating a gas-filled collision cell in a mass spectrometer is provided. The collision cell has a longitudinal axis. Ions are caused to enter the collision cell. A trapping field is generated within the collision cell so as to trap the ions within a trapping volume of the collision cell, the trapping volume being defined by the trapping field and extending along the longitudinal axis. Trapped ions are processed in the collision cell and a DC potential gradient is provided, using an electrode arrangement, resulting in a non-zero electric field at all points along the axial length of the trapping volume so as to cause processed ions to exit the collision cell. The electric field along the axial length of the trapping volume has a standard deviation that is no greater than its mean value.

Abstract: A system and method of mass spectrometry is provided. Ions from an ion source are stored in a first ion storage device and in a second ion storage device. Ions are ejected from the first ion storage device to a first mass analysis device during a first ejection time period, for analysis during a first analysis time period. Ions are ejected from the second ion storage device to a second mass analysis device during a second ejection time period. The ion storage devices are connected in series such that an ion transport aperture of the first ion storage device is in communication with an ion transport aperture of the second ion storage device. The first analysis time period and the second ejection time period at least partly overlap.

Abstract: A method of switching between two modes of power supply to a mass analyzer is provided. In a first mode of operation, operated for a first predefined time duration, a first power supply, coupled to the mass analyzer, generates a first nonzero potential, while a second power supply, disconnected from the mass analyzer, generates a second non-zero potential. In a second mode of operation, operated for a second predefined time duration, the second potential is coupled to the mass analyzer, while the first power supply, disconnected from the mass analyzer, generates the first potential. These predefined time durations are selected such that only one of: the first potential; and the second potential is coupled to the mass analyzer at any time, and such that the first and second modes of operation are carried out at least once within a predetermined length of time.