Abstract: The disclosed method and apparatus couple a membrane interface directly to a mass spectrometer at atmospheric pressure. The membrane may be in capillary or sheet form and allows the introduction of a liquid or gaseous sample to one side of the membrane while the other side of the membrane is bathed with a solution that can easily be used in an atmospheric pressure ionization source. Volatile molecules permeate through a suitable membrane such as poly-dimethyl silicone (PDMS), mix into the appropriate solvent, and are ionized. Because of the rules governing abstracts, this abstract should not be used in construing the claims.

Abstract: Apparatus including an ion trap, a controller connected to the ion trap, wherein the controller includes a memory containing computer readable instructions which, when executed, cause the controller to send control signals to the ion trap so that the ion trap produce and maintain a trapping field in the ion trap, a waveform generator to change the trapping field so that ions of a predetermined mass in the trapping chamber are selectively moved; a secondary waveform generator to change the orbits of the ions; an energy source to excite ions to emit photons, an optical detector to detect the emitted photons, and a processor which can apply fast-Fourier transform analysis of the time-domain signal of the detected emitted photons to generate a frequency or mass spectrum related to mass-to-charge ratio of the ions.

Abstract: An apparatus including a plurality of electrodes defining a trapping chamber of an ion trap, wherein at least one of the electrodes is a transparent electrode having at least a portion that is both optically transparent and electrically conductive; a controller connected to the plurality of electrodes, wherein the controller includes a memory containing computer readable instructions which, when executed, cause the controller to send control signals to the plurality of electrodes so that: the plurality of electrodes produce and maintain a trapping field in the trapping chamber, and the plurality of electrodes change the trapping field so that ions of a predetermined mass in the trapping chamber are selectively moved; and an optical detector oriented so that the portion of the transparent electrode that is both optically transparent and electrically conductive is between the optical detector and the trapping chamber.

Abstract: The disclosed method and apparatus couple a membrane interface directly to a mass spectrometer at atmospheric pressure. The membrane may be in capillary or sheet form and allows the introduction of a liquid or gaseous sample to one side of the membrane while the other side of the membrane is bathed with a solution that can easily be used in an atmospheric pressure ionization source. Volatile molecules permeate through a suitable membrane such as poly-dimethyl silicone (PDMS), mix into the appropriate solvent, and are ionized. Because of the rules governing abstracts, this abstract should not be used in construing the claims.

Abstract: An external ion source assembly in which ion are formed in an ion volume by the interaction of energetic electrons and gas molecules. The effective energy of the electrons entering the ion volume is controlled by changing the voltage between the electron source (filament) and the ionization volume whereby ions having sufficient energy for ionizing atoms and molecules leave the electron source and enter the ionization volume only during an ionization period. The ion source assembly can be used both for electron impact ionization (EI) and for chemical ionization (CI).

Abstract: A method of reducing noise due to undesolved charged droplets or charged particles in an ion trap mass spectrometer coupled to an atmospheric pressure ionization source.

Abstract: This invention is directed to a method and apparatus of increasing the dynamic range and sensitivity of an ion trap mass spectrometer with the use of external ionization. An increased number of sample ions are introduced into the mass spectrometer for mass analysis with the aid of an automatic ion supply control, or feedback, feature. The feedback portion of the invention controls the gating time, and hence the number of sample ions gated into the mass spectrometer, based on previous measurements of the ion content in the mass spectrometer to gate an amount relative to where space charge and saturation begins. A mass filter may also be used between the ion source and the mass spectrometer to improve the signal-to-noise ratio and increase the net processing time. This mass analyzing system may be used with various methods of mass analysis including mass selective instability, resonance ejection, MS/MS, and MS/MS with a supplemental AC field.

Abstract: The present invention relates generally to an ion trap mass spectrometer for analyzing ions and more particularly to a substantially quadrupole ion trap mass spectrometer with an enlarged ion occupied volume. Described herein are electrode geometries that enlarge the ion occupied volume. Improved ion sensitivities, detection limits and dynamic range should be realized for the same charge density in these devices because the increased ion occupied volume allows for the storage of a greater number of ions. The essence of this invention is that these ion trap geometries may apply all modes of operation of substantially quadrupole ion traps such as the mass selective instability mode, resonance excitation/ejection, and MS.sup.n.

Abstract: Disclosed is a multi-stage particle separator for separating analyte from non-analyte solvent in a fluid sample having nebulizing means to form droplets from the liquid sample and means coupled to the nebulizing means for adding helium to the nebulizing means. Furthermore, the multi-stage particle separator has a desolvation chamber for receiving the droplets, the desolvation chamber terminating in a nozzle, a multi-stage momentum separator including skimmers, and means for introducing a gas into one or more of the states to increase pressure of the latter stage so that the particles leave the multi-stage separator substantially free of solvent.

Abstract: A mass spectrometer including at least one mass analyzer into which an ion beam to be analyzed is projected having a collision surface means in-line with the ion beam to form surface collision products which are directed into the in-line mass analyzer.

Abstract: A device for introducing a sample into a mass spectrometer which generally comprises a probe which is connected to the mass spectrometer and a semipermeable capillary tube connected at the end of the probe. The probe includes conduit passageways for permitting bidirectional fluid flow through the probe, and the capillary tube is connected to the end of the probe so as to permit the flow of a fluid containing the sample to be analyzed through the probe and the capillary tube. This fluid flow through the capillary tube will enable at least a portion of the sample to be transferred into the mass spectrometer via diffusion through the capillary tube.

Abstract: A method of vaporizing a multicomponent liquid, such as a hydrogen peroxide and water solution, for injection into a vacuum chamber including the steps of metering successive predetermined increments of the liquid at a predetermined rate onto a heated surface in a vaporization chamber. Upon exposure to the heated surface, each liquid increment is substantially instantaneously vaporized before the next succeeding liquid increment is metered onto the heated surface to produce a multicomponent vapor increment having substantially the same weight percent composition as the multicomponent liquid increment. Each vapor increment is passed into the vacuum chamber.

Abstract: A method of vaporizing a multicomponent liquid, such as a hydrogen peroxide and water solution, for injection into a vacuum chamber including the steps of metering successive predetermined increments of the liquid at a predetermined rate onto a heated surface in a vaporization chamber. Upon exposure to the heated surface, each liquid increment is substantially instantaneously vaporized before the next succeeding liquid increment is metered onto the heated surface to produce a multi-component vapor increment having substantially the same weight percent composition as the multicomponent liquid increment. Each vapor increment is passed into the vacuum chamber.