Abstract: In one aspect, a mass spectrometer is disclosed, which comprises an ion trap having a plurality of electrodes arranged in a multipole configuration so as to provide an inlet for receiving ions along a longitudinal axis into a space between the electrodes, where at least one of the plurality of electrodes comprises a passageway through which ions can be extracted radially from the ion trap. The electrodes are configured for application of one or more RF voltages thereto for providing radial confinement of the ions, and a DC voltage source configured to apply a dipolar DC voltage pulse across said at least one electrode and an opposed electrode for causing radial extraction of at least a portion of said ions from said ion trap through said passageway.

Abstract: Systems and methods are disclosed for ion injection into an electrostatic trap. As non-limiting examples, various aspects of this disclosure provide a quadrupole comprising first, second, and third quadrupole segments. The second quadrupole segment may be arranged between the first and third quadrupole segments and the first quadrupole segment and the third quadrupole segment may each comprise four poles with auxiliary electrodes arranged between each pair of the four poles. The second quadrupole segment may comprise four poles and the first and third quadrupoles each may comprise four individual auxiliary electrodes, two pairs of auxiliary electrodes, two electrodes, or one pair of auxiliary electrodes. The auxiliary electrodes of the first quadrupole segment and the entrance lens may be biased at a same direct current (DC) voltage. The auxiliary electrodes of the third quadrupole segment and the exit lens may be biased at a same DC voltage.

Abstract: Systems and methods are disclosed for ion injection into an electrostatic trap. Various aspects of this disclosure provide a mass spectrometer system including a primary ion path including a plurality of quadrupoles; and a secondary ion path coupled to the primary ion path utilizing turning elements. The secondary ion path may include an electrostatic linear ion trap (ELIT), the ELIT being operable to analyze ions diverted from the primary ion path and return them to the primary ion path. The primary ion path may include a time-of-flight mass analyzer. The secondary ion path may be bi-directional. Ions may travel in a first direction when coupled into the secondary ion path using a first turning element in the primary ion path and may travel in a second direction when coupled into the secondary ion path utilizing a second turning element in the primary ion path. The secondary ion path may include a collision quadrupole.

Abstract: A Fourier Transform electrostatic linear ion trap (ELIT) is disclosed with an electron multiplier detector comprising one of a microchannel plate and a channel electron multiplier. An (ELIT) is provided comprising a central axis along which ions travel; an image current detector disposed at least partially around the central axis of the ELIT; and an electron multiplier detector arranged in an opening of the image current detector, the electron multiplier detector being operable to receive ions deflected from the central axis. The electron multiplier detector may have a front surface that is perpendicular to the central axis of the ELIT. The electron multiplier detector may comprise two separate elements at non-normal angles to the central axis of the ELIT. The image current detector may comprise a cylinder with the opening on one side in which the electron multiplier detector is arranged, a U-shape, or a half-tube detector.

Abstract: An ion guide defining a guide axis receives ions. The ion guide applies a potential profile that includes a pseudopotential well to the ions using an ion control field. The ion control field includes a component for restraining movement of the ions normal to the guide axis and a component for controlling the movement of the ions parallel to the guide axis. The ion guide sequentially injects the ions with the same ion energy and in decreasing order of m/z value into an ELIT aligned along an ELIT axis to focus the ions irrespective of m/z value at the same location on the ELIT axis within the ELIT at the same time by varying a magnitude of the pseudopotential well. The ELIT can trap the focused ions using in-trap potential lift or mirror-switching ion capture.

Abstract: An ELIT includes voltage sources (1101), switches (1102), a first set of electrode plates (1110) aligned along a central axis, and a second set of electrode plates (1120) aligned along the central axis with the first set. A first group of plates (310, 320; 810, 820) of the first set and the second set is positioned to trap ions within a first path length (340, 940). A second group of plates (410, 420) of the first set and the second set is positioned to trap ions within a shorter second path length (440, 1040). The switches select the first path length by applying voltages from the voltage sources to the first set and the second set that cause the first group of plates to trap ions within the first path length. Alternatively, the switches can select the second path length by applying voltages that cause the second group of plates to trap ions within the second path length.

Abstract: An ion guide defining a guide axis receives ions. The ion guide applies a potential profile that includes a pseudopotential well to the ions using an ion control field. The ion control field includes a component for restraining movement of the ions normal to the guide axis and a component for controlling the movement of the ions parallel to the guide axis. The ion guide sequentially injects the ions with the same ion energy and in decreasing order of m/z value into an ELIT aligned along an ELIT axis to focus the ions irrespective of m/z value at the same location on the ELIT axis within the ELIT at the same time by varying a magnitude of the pseudopotential well. The ELIT can trap the focused ions using in-trap potential lift or mirror-switching ion capture.

Abstract: An MCP detector (620) receives an ion packet along an ion path (601) of mass spectrometer through a hollow central cylindrical tube (621) of the MCP detector. The MCP detector includes coaxial rings (622) of MCPs surrounding the hollow central cylindrical tube. The MCP detector transmits the ion packet along the ion path to an ELIT (610) through holes in the center of a first set of reflectron plates (613) of the ELIT to oscillate the ion packet between the first set and a second set of reflectron plates (614) of the ELIT. The ELIT transmits the oscillated ion packet back to the MCP detector along the ion path through the holes of the first set. The MCP detector detects ions of the oscillated ion packet that are radially deflected from the ion path using the rings of MCPs. The MCP detector allows ions to be transmitted to or from either port of the ELIT.

Abstract: A mass spectrometer is operated to simultaneously measure precursor and production data over a number of acquisitions. For each acquisition, the following steps are performed. Ion transfer optics inject ions from an ion beam into an ELIT causing the ions to oscillate axially between two electric fields produced by two the sets of reflectrons. The ELIT measures a time domain image current of the oscillating ions from ion injection to a total acquisition time, Tacq1, and fragments the oscillating ions at one or both turning points of the oscillating ions adding product ions to the oscillating ions. The fragmentation is performed at a delay time relative to the ion injection that is increased by a time increment in each subsequent acquisition making the fragmentation dependent on ion position. The measured time domain image current is stored as a row or column of a two-dimensional matrix.

Abstract: One or more ions are received along a central axis through a first set of reflectron plates of an ELIT. Voltages are applied to the first set of plates and to a second set of reflectron plates in order to trap and oscillate the one or more ions. A first induced current is measured from a cylindrical pickup electrode between the first set of reflectron plates and the second set of reflectron plates. A second induced current is measured from one or more plates of the first set of reflectron plates. A third induced current is measured from one or more plates of the second set of reflectron plates. The first measured induced current, second measured induced current and third measured induced current are combined to reduce higher order frequency harmonics of the induced current.

Abstract: A mass spectrometer is operated to simultaneously measure precursor and production data over a number of acquisitions. For each acquisition, the following steps are performed. Ion transfer optics inject ions from an ion beam into an ELIT causing the ions to oscillate axially between two electric fields produced by two the sets of reflectrons. The ELIT measures a time domain image current of the oscillating ions from ion injection to a total acquisition time, Tacq1, and fragments the oscillating ions at one or both turning points of the oscillating ions adding product ions to the oscillating ions. The fragmentation is performed at a delay time relative to the ion injection that is increased by a time increment in each subsequent acquisition making the fragmentation dependent on ion position. The measured time domain image current is stored as a row or column of a two-dimensional matrix.

Abstract: One or more ions are received along a central axis through a first set of reflectron plates of an ELIT. Voltages are applied to the first set of plates and to a second set of reflectron plates in order to trap and oscillate the one or more ions. A first induced current is measured from a cylindrical pickup electrode between the first set of reflectron plates and the second set of reflectron plates. A second induced current is measured from one or more plates of the first set of reflectron plates. A third induced current is measured from one or more plates of the second set of reflectron plates. The first measured induced current, second measured induced current and third measured induced current are combined to reduce higher order frequency harmonics of the induced current.