Patent classifications
H01J49/423
MASS SPECTROMETER, ION OPTICAL DEVICE, AND METHOD FOR ION MANIPULATION IN MASS SPECTROMETER
The invention provides a mass spectrometer, an ion optical device, and a method for ion manipulation in a mass spectrometer. The mass spectrometer includes a mass analyzer; and an ion guiding device, including two electrode arrays positioned in parallel with each other, each electrode array including at least two ring electrodes concentrically disposed or at least three linear electrode assemblies having a radial distribution; and a power supply means, configured to apply a voltage on at least a part of the ring electrodes, to form a radio-frequency electric field and a DC electric field. By means of the radio-frequency electric field and the DC electric field, ions are allowed to be stored in a region between the two arrays, and controlled to be sequentially released along a radial direction according to a preset mass-to-charge ratio requirement, then exit the ion guiding device and enter the mass analyzer for mass analysis.
Ion beam mass pre-separator
An apparatus for separating ions includes an electrode arrangement having a length extending between first and second ends. The first end is configured to introduce a beam of ions into an ion transmission space of the arrangement. An electronic controller applies an RF potential and a DC potential to an electrode of the electrode arrangement, for generating a ponderomotive RF electric field and a mass-independent DC electric field. The application of the potentials is controlled such that a ratio of the strength of the ponderomotive RF electric field to the strength of the mass-independent DC electric field varies along the length of the electrode arrangement. The generated electric field supports extraction of ions having different m/z values at respective different positions along the length of the electrode arrangement. Ions are extracted in one of increasing and decreasing sequential order of m/z ratio with increasing distance from the first end.
ION EXCITATION METHOD IN LINEAR ION TRAP
The present invention relates to the technical field of mass analysis instruments. Disclosed is an ion excitation method in a linear ion trap. The method comprises: in a linear ion trap, and at an ion collision-induced dissociation stage, simultaneously applying an auxiliary excitation signal in radial X and Y directions thereof; increasing the kinetic energy of ions in the two directions, thereby increasing collisions with a center gas to cause dissociation; and converting the kinetic energy to internal energy to achieve tandem mass spectrometry analysis. The kinetic energy in the X and Y directions of the ion is increased, and compared to a conventional dissociation method in which ions are primarily excited in one direction, more kinetic energy is converted to internal energy, thus improving dissociation efficiency, shortening reaction time, and addressing a low mass cutoff effect in the ion trap.
High duty cycle ion spectrometer
An ion spectrometer is provided, comprising: an ion source, arranged to generate ions continuously with a first range of mass to charge ratios; and an ion trap, arranged to receive ions from the ion source along an axis, and to eject ions with a second range of mass to charge ratios orthogonally to that axis, the second range of mass to charge ratios being narrower than the first range of mass to charge ratios. In some embodiments, ions generated by the ion source continuously flow into the ion trap. Additionally or alternatively, ion optics receive ions ejected from the ion trap and cool the ions without substantial fragmentation. An ion analyser receives ions ejected from the ion trap or ion optics and separates the ions in accordance with at least one characteristic of the ions.
Method for Removing Trapped Ions from a Multipole Device
A method and apparatus for clearing ions from a multipole ion transmission device which includes introducing a DC or RF clear out pulse to one or more of the rods of the multipole device. The DC pulse is selected so as to supply sufficient kinetic energy to the ions to overcome a pseudo-potential trapping well generated by the RF potentials of the ion transmission device. For an RF pulse, the auxiliary RF signal uses frequencies that correspond to the ejected ion's frequencies of motion. In select embodiments, the multipole device can be a quadrupole or the apparatus can be part of a tandem mass spectrometer.
Lateral introduction of ions into RF ion guides
An ion guide system includes an ion guide with pole rods, a device for laterally introducing an ion species, and a mass spectrometer for analyzing product ions of reactions between different ion species. The device is configured and positioned such that an RF field with at least two-fold rotational symmetry with respect to the axis is generated. The device includes shortened pole rods and/or further electrodes. The pole rods and the further electrodes have at least two-fold rotational symmetry. The symmetry of the RF field allows ions to travel straight ahead through the ion guide with no hindrance. Such arrangements are particularly suitable for bringing together largely loss-free positive and negative ion species for reacting them. The reactions may be used to fragment multiply charged biopolymer ions by electron transfer or to remove excess charges of multiply charged biopolymer ions.
Multi-turn time-of-flight mass spectrometer
An MT-TOFMS which is one mode of the present invention includes: a linear ion trap (2) configured to temporarily hold ions to be analyzed, and to eject the ions through an ion ejection opening (211) having a shape elongated in one direction; a loop flight section (3) configured to form a loop path (P) capable of making ions repeatedly fly; and a slit part (5) located on an ion path in which the ions ejected from the linear ion trap (2) travel until the ions are introduced into the loop path, the slit part configured to block a portion of the ions in a longitudinal direction of the ion ejection opening (211).
Methods and systems for quantitative mass analysis
A method of quantitative mass analysis of precursor species of different mass-to-charge (m/z) ratios from the same ion injection event is disclosed. A plurality of precursor ion species is introduced into a mass spectrometer at the same time, and isolated. A first subset of the isolated precursor ions having a first m/z ratio and a second subset of the isolated precursor ions having a second m/z ratio are fragmented. The fragmented ions are analyzed at the same time. A mass spectrum is generated for the fragment ions of the first and second subsets of precursor ions.
Systems and methods for ion isolation
A mass spectrometer includes a radio frequency ion trap and a controller. The controller is configured to cause an ion population to be injected into the radio frequency ion trap and supply an isolation waveform to the radio frequency ion trap. The isolation waveform has at least one notch at a target mass-to-charge ratio and a frequency profile determined to eject unwanted ions at a plurality of frequencies in a substantially similar amount of time.
Systems and methods for reducing the kinetic energy spread of ions radially ejected from a linear ion trap
A system for analyzing a sample includes a linear ion trap, an insert DC electrode, a voltage controller, and an RF control circuitry. The linear ion trap includes a first pair of trap electrodes and a second pair of trap electrodes spaced apart from each other and surrounding a trap interior. An electrode of the second pair of trap electrodes includes a trap exit. The insert DC electrode is positioned adjacent to the trap exit. The voltage controller applies a DC voltage to the insert DC electrode. The RF control circuitry applies a main RF voltage to the first pair of trap electrodes, applies a portion of the main RF to the second pair of trap electrodes, increases the main RF applied to the first pair of trap electrodes, and applies an auxiliary RF voltage to the second pair of trap electrodes.