Abstract:
In a mass spectrometer that uses a space-restricted magnetic field, such as an ion cyclotron resonance mass spectrometer, ions with a wide mass range generated in an ion supply located outside the magnetic field are transported in the direction of the magnetic field lines to an ion storage device located inside the magnetic field without losing ions by guiding the ions through the region in which the magnetic field strength increases with a special ion guide. This ion guide consists of an arrangement of coaxial ring diaphragms which are alternately supplied with the phases of an RF voltage. In an alternative embodiment, the ion guide uses two wires wound in a double helix where each wire is supplied with one phase of a two-phase RF voltage.
Abstract:
A mass spectrometric analysis of surface material is performed by vaporizing the surface material with pulses of laser light and then collecting the vaporized material by dissolving it in a liquid. The liquid with the dissolved material is then fed to an ionization process, preferably an electrospray ionization process. The resulting ions are then analyzed with a mass spectrometer. The method is particularly suited for use with imaging mass spectrometry.
Abstract:
The invention relates to a measuring cell for an ion cyclotron resonance mass spectrometer (FTMS). The invention provides a measuring cell which, on the one hand, consists of two ion-repelling RF grids at the front ends as trapping electrodes and thus produces a pure cyclotron motion of the ions without the usually co-existing magnetron motion and, on the other hand, measures a multiplied cyclotron frequency by means of a plurality of detection electrodes, whereby either a higher mass accuracy or a shorter measuring time can be achieved.
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:
Components of a mixture are separated by feeding charged molecules of the components into a end surface of a suitable medium, for example a gel. The molecules are drawn in a first direction through the medium by means of an DC electric field, while at the same time being subjected to an alternating voltage with a strongly asymmetric profile in a direction transverse to the first direction. The nonlinear behavior of the electrically-generated migration causes a large number of molecules to migrate transversely out of the medium while only a small number of molecules reach the opposite end surface of the medium. A superimposed DC voltage in the transverse direction selects which of the mixture components migrate all the way through the medium in the first direction. The separated components can be sampled from the opposite end surface and from points on the upper and lower medium surfaces.
Abstract:
The invention relates to the ionization of analyte molecules on a solid surface close to atmospheric pressure as an ion source for mass spectrometers. The invention uses a spray mist from an electrospray apparatus to ionize the analyte molecules, for example a spray mist created by spraying pure water, which generates predominantly multiply charged ions of the analyte molecules which are particularly suitable for fragmentation.
Abstract:
The invention relates to a measuring cell for an ion cyclotron resonance mass spectrometer (FTMS). The invention provides a measuring cell which, on the one hand, consists of two ion-repelling RF grids at the front ends as trapping electrodes and thus produces a pure cyclotron motion of the ions without the usually co-existing magnetron motion and, on the other hand, measures a multiplied cyclotron frequency by means of a plurality of detection electrodes, whereby either a higher mass accuracy or a shorter measuring time can be achieved.
Abstract:
The invention relates to a device and a method for producing, from any previously configured ion beams, precisely localized small packages of ions which all fly at the same velocity. The invention consists of damping the ions in a damping-gas filled series of apertured diaphragms (which are firstly subjected alternately to the two phases of an RF voltage and secondly to a multiphase low-frequency travelling field voltage) into the axis of the apertured diaphragm arrangement and packaging the ions in bundles which are propelled axially at the same velocity for ions of different specific masses. These ion packages, which are restricted both in an axial and a radial direction, can be used to advantage for injection into different types of mass spectrometer, both storage ion-trap mass spectrometers, such as cyclotron resonance mass spectrometers or quadrupole ion traps and, especially, for time-of-flight mass spectrometers with orthogonal injection. The arrangement of a damping-gas filled series of apertured diaphragms can also be used for ion fragmentation.
Abstract:
An ion funnel screen ions from a gas stream flowing into a differential pump stage of a mass spectrometer, transfers them to a subsequent differential pump stage. The ion funnel uses apertured diaphragms between which gas escapes easily. Holders for the apertured diaphragms are also provided that offer little resistance to the escaping gas while, at the same time, serving to feed the RF and DC voltages.
Abstract:
The invention relates to the mass-selective ejection of stored ions from linear ion traps. The invention consists in using nonlinear resonances to enhance the ejection speed.