Other

Bruker Daltonics, Inc.

Agilent Technologies, Inc.

Varian, Inc.

Felician Muntean

Urs Steiner

Roy P Moeller

Stephen Zanon

Maurizio Splendore

Desmond Allen Kaplan

Melvin Andrew Park

Bert David Egley

Mingda Wang

Mark Ridgeway

Anil Mavanur

Jens Bossmeyer

Rohan Thakur

Chaminda M Gamage

Thinh M Ha

Charles A Fancher

The invention relates to mass spectrometers having secondary electron multipliers with series of discrete dynode stages. The invention particularly relates to an operation with extended dynamic measuring range and extended lifetime. The invention is based on not adapting the dynamic measuring range by control of the gain of the trans-impedance amplifier, nor controlling the multiplier operating voltage, which both are usually too slow, but alternating a number of active and passive dynode stages of a discrete dynode multiplier. Each dynode stage is connected to a discrete voltage supply circuit, being able to be de-energized and short-cut; the multiplier gain is feedback-controlled by energizing or short-cutting dynode stages, serially from the end of the multiplier, as a function of a last measured ion signal; and the multiplier has a single trans-impedance amplifier and a single analog-to-digital converter, measuring and digitizing the output current of the last active dynode stage.

Mass spectrometer having multi-dynode multiplier(s) of high dynamic range operation

The disclosure relates to a mass spectrometer, comprising (a) a vacuum recipient containing ion handling elements of the mass spectrometer, the vacuum recipient having a plurality of walls which define a gastight volume and comprise at least one of an entrance and exit, wherein different portions of an ion path pass at least one of the entrance and exit and run through the gastight volume; and (b) a gastight radio frequency ion guide having an ion passage along an axis and being mounted gastight to at least one of the entrance and exit as to continue the ion path in its ion passage outside the gastight volume. Embodiments of the disclosure facilitate, in particular, reducing pumping volumes in the mass spectrometer and corresponding pumping requirements as well as lowering the size and weight of such an assembly.

Mass spectrometer using gastight radio frequency ion guide

The invention relates to a mass spectrometer, comprising an ion guide having a plurality of electrodes that are supplied with a radio frequency voltage to facilitate radial confinement of ions in an internal volume defined by inward facing surfaces of the electrodes, the internal volume including a first section having a variable radial diameter along a longitudinal axis of the ion guide, in which the electrodes are helically wound, and an adjacent second section having a substantially constant radial diameter along the longitudinal axis, wherein the electrodes extend from the first section to the second section continuously. The continuous nature of the ion guide electrodes facilitates in particular unhindered axial propagation of ions through the assembly and prevents ion losses during their transmission through different compartments of the mass spectrometer.

Mass spectrometer comprising a radio frequency ion guide having continuous electrodes

The invention provides a method for acquiring fragment ion spectra of substances in complex substance mixtures wherein a trapped ion mobility spectrometer ('TIMS') is used as the ion mobility separation device coupled to a triple quadrupole mass filter assembly. The fragment ion spectra may be used for the identification of high numbers of proteins in complex mixtures, or for a safe quantification of some substances, by their fragment ion mass spectra in a mass spectrometer with upstream substance separator. TIMS, in particular equipped with parallel accumulation, provides the unique possibility to prolong the ion accumulation duration to find more detectable ion species without decreasing the measuring capacity for fragment ion mass spectra. The high measurement capacity for fragment ion mass spectra permits the repeated measurement of low abundance ion species such as to improve the quality of the fragment ion spectra.

Triple quadrupole mass spectrometry coupled to trapped ion mobility separation

The invention relates to a mass spectrometer having an electron impact ionization source which comprises an ejector for forming a beam of sample gas being driven in a first direction through an interaction region; a magnet assembly configured and arranged such that its magnetic field lines pass through the interaction region substantially parallel to the first direction; an electron emitter assembly for directing electrons toward the interaction region in a second direction being aligned substantially opposite to the first direction, wherein the electrons propagate along and are confined about the magnetic field lines until reaching the interaction region and forming sample gas ions therein; and a mass analyzer located downstream from the interaction region to which the sample gas ions are guided for mass analysis.

Magnetically assisted electron impact ion source for mass spectrometry

The invention provides a cathode system for an Electron Ionization (EI) source comprising a filament and current supply posts, the current supply posts dividing the filament into segments and each current supply post supplying or returning the current for at least two segments of the filament. Each filament segment is connected, for instance by spot welding, to the supply posts delivering the heating current. The filament segments may be arranged in a row, or substantially parallel to each other. Filament segments arranged in a row may form a closed loop, for instance, a ring. Other embodiments encompass the filament shape of a helical coil.

Filament for mass spectrometric electron impact ion source

The invention relates to a radio frequency ion guide construction for use in mass spectrometry that minimizes contamination by allowing ions rejected by the RF confinement field to fly through and away from the ion guide electrodes and preventing them from hitting the sensitive electric potential defining surfaces of the ion guide electrodes. At the entrance end of the ion guide, each electrode of the plurality of electrodes has a front end that is forked or that contains a recessed feature facing an interior of the ion guide. For an electrode that is forked, the teeth of the forked end may have different shapes or tapers, and a conductive mesh may be used to cover a gap between the teeth. Similarly, for an electrode that has a recessed feature, a conductive mesh may cover the recessed feature.

Contamination-proof ion guide for mass spectrometry

An ion guide includes a plurality of curved electrodes and an ion deflecting device. The electrodes are arranged in parallel with each other and with a central curved axis, the curved central axis being co-extensive with an arc of a circular section having a radius of curvature, each electrode being radially spaced from the curved central axis, wherein the plurality of electrodes define a curved ion guide region arranged about the curved central axis and between opposing pairs of the electrodes. The ion deflecting device may include a device for applying a DC electric field to two or more of the electrodes in a radial direction. The ion deflecting device may include a pair of curved, parallel ion deflecting electrodes, which are in addition to curved electrodes utilized for applying an RF ion guiding field.

Curved ion guide and related methods

The invention generally relates to an assembly of a first RF component and a second RF component in a mass spectrometer, the first RF component comprising a first set of electrodes and the second RF component comprising a second set of electrodes, wherein the RF components are located and aligned end-to-end to one another, and wherein a transverse dimension of the electrodes of the first set is smaller than that of the electrodes of the second set. The assembly further comprises a conductive electric field screen located at an outer periphery of the first set of electrodes and facing the electrodes of the second set as to reduce RF electric field cross-talk between the electrodes of the first set and those of the second set. The invention affords for technically simple and economic means to reduce cross-talk or capacitive coupling between adjacent RF components in a mass spectrometer.

Reduction of cross-talk between RF components in a mass spectrometer

An assembly for use in an electrospray ion source includes a capillary for guiding a flow of liquid generally containing analyte(s) of interest, which is to be electrosprayed into an ionization chamber, a first tube at least partially encasing the capillary such that a first conduit for guiding a first heatable gas is created proximate the capillary and a hollow member that has an internal evacuated space and is located at the outer circumference of the capillary such that heat transfer from the first heatable gas flowing proximate the capillary to the liquid in the capillary is impeded. The assembly provides a simple and lean/compact way of preventing excessive heat transfer to the liquid in the capillary of an electrospray ion source.

Assembly for an electrospray ion source

A transfer line for conveying the column effluent from a gas chromatograph to an ion source of a mass spectrometer has a transfer line body and a mechanism for moving the transfer line body either towards or away from the mass spectrometer. A gas seal between the housing of the mass spectrometer and the transfer line body prevents vacuum leak when the transfer line body is moved. In one embodiment, the transfer line body outer periphery is threaded and a hand wheel engages the transfer line body threads via complementary threads in order to move the body. When the transfer line is moved towards the mass spectrometer, the body presses an ion source, which is not rigidly fixed to the housing of the mass spectrometer, into a recess seat of the housing, and aligns the ion source in an operating position.

Gas chromatograph-mass spectrometer transfer line

An ion optics assembly is formed by four quarter-circular profile elements, all of which are attach to the same reference plate. Consequently, all four elements remain aligned to the same reference plate. The four elements form a quarter-circular channel with quarter-circular quad electrodes. The quad electrodes receive electrical potential to form the field required to focus and maintain the ions at the center of the channel. Quarter-circular insulators are provided on all sides of the channel so as to seal the channel over its length from the interior of the mass spectrometer. A heater is provided at the entrance to the ion transfer optics, to prevent accumulation of ions on the poles. A thermal break is provided in the quad, so as to enable maintaining the front of the quad heated and the rest of the quad cooler.

Curved heated ion transfer optics

A method and apparatus for transmitting ions in a mass spectrometer from an ion source to a mass analyzer extracts analyte ions from the ion source in such a manner that the number of extracted analyte ions is maximized. The ions are then transmitted through an ion guide to the mass analyzer. The ion guide is filled with an interaction gas and its operating parameters are adjusted so that, as the ions pass through the ion guide, the analyte ion energy distribution width is narrowed and the analyte ions are collimated within the ion guide to improve the resolution and sensitivity of the mass analyzer.

Method and apparatus for transmitting ions in a mass spectrometer maintained in a sub-atmospheric pressure regime

An ion collision cell is fabricated by four semi-circular profile elements, all of which are attach to the same reference plate. Consequently, all four elements remain aligned to the same reference plate. The four elements form a semi-circular channel with a semi-circular quad electrodes. The quad electrodes receive electrical potential to form the field required to focus and maintain the ions at the center of the channel. semi-circular insulators are provided on all sides of the channel so as to seal the channel over its length from the interior of the mass spectrometer.

Lens free collision cell with improved efficiency

An ion guide includes a plurality of curved electrodes and an ion deflecting device. The electrodes are arranged about and radially spaced from a central curved axis, and circumscribe a curved ion guide region from an ion entrance to an ion exit. The ion deflecting device may include a device for applying a DC electric field to one or more electrodes in a radial direction. The magnitude of the DC electric field, and thus the ion deflecting force, varies along the curved axis. The ion guide may for example operate as a collision cell or like instrument.

Growing community of inventors

Danville, CA, United States of America

Felician Muntean