Abstract: The invention relates to a method and a device for introducing ions into an ICR cell of Fourier transform ion cyclotron resonance mass spectrometers, in particular with a reduced the magnetron orbit. The invention is based on applying at least one gated DC voltage to a mantle electrode of the ICR cell prior to the excitation of the cyclotron motion such that injected ions are deflected inside the ICR cell in at least one radial direction.

Abstract: Fine structures of isotopic peak clusters of substances are determined using ultrahigh resolution mass spectrometry, e.g, FT-ICR mass spectrometry. Resolved individual peaks in the fine structure of the non-monoisotopic peak clusters of organic substances usually contain the additional elemental isotopes 13C, 15N, 17O, 18O, 2H, 33S, 34S, and combinations thereof. In each of a series of experiments, one of the non-monoisotopic peak clusters is isolated and the corresponding fine structure spectrum acquired. Abundances of the resolved fine structure peaks and their positions on the mass scale are recorded and, after measuring some or all of the isotopic peaks, the atomic composition of the measured substance is calculated. By excluding the monoisotopic peak and isolating only one isotopic peak cluster at a time, the number of ions in the FT-ICR cell is kept low, which avoids resolving power losses due to space charge effects and ion-ion interaction phenomena.

Abstract: The invention relates to a method and a device for introducing ions into an ICR cell of Fourier transform ion cyclotron resonance mass spectrometers, in particular with a reduced the magnetron orbit. The invention is based on applying at least one gated DC voltage to a mantle electrode of the ICR cell prior to the excitation of the cyclotron motion such that injected ions are deflected inside the ICR cell in at least one radial direction.

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 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: 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: 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: An ion cell having an axis includes a sheath of individual electrodes that extends along the axis and defines an internal volume. Adjacent individual electrodes are electrically insulated from each other. The individual electrodes each receive a DC potential and RF voltage. At least some of the individual electrodes have a width that varies in the axial direction such that an electrical effect on an axis potential varies along the axis of the ion cell.

Abstract: The compensation potentials on the compensation electrodes of an ICR measuring cell are sequentially adjusted so that an ICR measurement with the longest possible usable image current transient is produced. Then, subsequent ICR measurements are made using the ICR cell with the optimally adjusted compensation potentials. Depending on the kind of ion mixture involved, measurements with image current transients from 10 to more than 20 seconds long can be performed, from which mass spectra with a maximum mass resolution without peak coalescence can be obtained.

Abstract: In an ion mobility spectrometer, ions are generated, mobility-separated and deposited on a receiver, preferably at spatially separated positions by soft landing or crash landing techniques. The ion mobility spectrometer can be a stand-alone instrument or part of a hybrid analysis instrument. To analyze the deposited ions, the receiver is removed from the vacuum system of the ion mobility spectrometer and introduced into an analytical instrument. Various physical, chemical, and biological analysis techniques and instrumentation can be used, such as mass spectrometry or surface analytical techniques, by selecting a special receiver suitable for the desired analytical technique.

Abstract: Ion mobilities are measured by entraining the ions in a gas and adiabatically expanding the ion-containing gas through a nozzle to form a gas jet. An electrical field barrier with variable height is located at the nozzle exit. The field barrier may be located adjacent to the nozzle exit or an ion guide may be located between the nozzle and the field barrier. If a continuous ion current is supplied, the height of the barrier is varied and the ion current of the ions passing over the barrier is measured, the ion current can be differentiated to generate a mobility spectrum. Alternatively, the ions can be temporarily stored in the ion guide so that measurement of the ion current of the ions passing over the barrier results in a direct measurement of the mobility spectrum.

Abstract: An ion cell having an axis includes a sheath of individual electrodes that extends along the axis and defines an internal volume. Adjacent individual electrodes are electrically insulated from each other. The individual electrodes each receive a DC potential and RF voltage. At least some of the individual electrodes have a width that varies in the axial direction such that an electrical effect on an axis potential varies along the axis of the ion cell.

Abstract: The mobility of mass-selected ions in gases is measured at pressures of a few hectopascal by selecting the ions under investigation in a quadrupole filter according to their mass-to-charge ratio m/z, measuring their mobility in a drift region at a pressure of a few hundred Pascal under the influence of a DC electric field and then filtering the measured ions by means of a quadrupole field in order to eliminate, or detect changes in, the mass-to-charge ratio. Several embodiments for the drift region are disclosed, in which the ions are kept in the axis of the drift region by RF fields. As these drift regions can also be utilized for a collision-induced decomposition of the ions, the device can additionally be used as a so-called triple quadrupole mass spectrometer.

Abstract: The compensation potentials on the compensation electrodes of an ICR measuring cell are sequentially adjusted so that an ICR measurement with the longest possible usable image current transient is produced. Then, subsequent ICR measurements are made using the ICR cell with the optimally adjusted compensation potentials. Depending on the kind of ion mixture involved, measurements with image current transients from 10 to more than 20 seconds long can be performed, from which mass spectra with a maximum mass resolution without peak coalescence can be obtained.

Abstract: The invention relates to instruments for storing ions in more than one ion storage device and to the use of the storage bank thus created. The ion storage bank includes several storage cells configured as RF multipole rod systems, where the cells contain damping gas and are arranged in parallel. Each pair of pole rods is used jointly by two immediately adjacent storage cells such that the ions collected can be transported from one storage cell to the next by briefly applying DC or AC voltages to individual pairs of pole rods. The ions can thus be transported to storage cells in which they are fragmented or reactively modified, or from which they can be fed to other spectrometers. In particular, a circular arrangement of the storage cells on a virtual cylindrical surface makes it possible to accumulatively fill the storage cells with ions of specific fractions from temporally sequenced separation runs.

Abstract: Ion mobilities are measured by entraining the ions in a gas and adiabatically expanding the ion-containing gas through a nozzle to form a gas jet. An electrical field barrier with variable height is located at the nozzle exit. The field barrier may be located adjacent to the nozzle exit or an ion guide may be located between the nozzle and the field barrier. If a continuous ion current is supplied, the height of the barrier is varied and the ion current of the ions passing over the barrier is measured, the ion current can be differentiated to generate a mobility spectrum. Alternatively, the ions can be temporarily stored in the ion guide so that measurement of the ion current of the ions passing over the barrier results in a direct measurement of the mobility spectrum.

Abstract: In an ion cyclotron resonance mass spectrometer in which ions are trapped axially by applying electrical potentials to a pattern of electrode elements to produce an inhomogeneous alternating radio-frequency electric field with a repulsive effect, an additional electrostatic ion-attracting field is superimposed on the repulsive electric field. The voltage of the ion-attracting field is adjusted to compensate for a cyclotron frequency shift of the ions caused by the ion space charge. The voltage of the ion-attracting field can be adjusted so that the ion cyclotron frequency of all ions becomes independent of the number of ions inside the spectrometer.

Abstract: In an ion cyclotron resonance mass spectrometer in which ions are trapped axially by applying electrical potentials to a pattern of electrode elements to produce an inhomogeneous alternating radio-frequency electric field with a repulsive effect, an additional electrostatic ion-attracting field is superimposed on the repulsive electric field. The voltage of the ion-attracting field is adjusted to compensate for a cyclotron frequency shift of the ions caused by the ion space charge. The voltage of the ion-attracting field can be adjusted so that the ion cyclotron frequency of all ions becomes independent of the number of ions inside the spectrometer.

Abstract: The invention relates to methods and devices for regulating the filling level in measuring cells of ion cyclotron resonance mass spectrometers so that it is optimal for mass resolution and mass accuracy. The invention consists in supplying a fraction of the samples to a second reference mass spectrometer operated in parallel, and employing the mass spectra obtained from this reference mass spectrometer to regulate the filling level in the ion cyclotron resonance mass spectrometer.

Abstract: The mobility of mass-selected ions in gases is measured at pressures of a few hectopascal by selecting the ions under investigation in a quadrupole filter according to their mass-to-charge ratio m/z, measuring their mobility in a drift region at a pressure of a few hundred Pascal under the influence of a DC electric field and then filtering the measured ions by means of a quadrupole field in order to eliminate, or detect changes in, the mass-to-charge ratio. Several embodiments for the drift region are disclosed, in which the ions are kept in the axis of the drift region by RF fields. As these drift regions can also be utilized for a collision-induced decomposition of the ions, the device can additionally be used as a so-called triple quadrupole mass spectrometer.