Agilent Technologies, Inc.

Varian, Inc.

Kenneth R Newton

James L Bertsch

Mark Denning

August Specht

Bert David Egley

Mingda Wang

Alexander Mordehai

Nigel P Gore

Trygve Ristroph

Guthrie Partridge

Layne Evan Howard

Dave Deford

Doris Lee

Steve Schachterle

Electron capture dissociation (ECD) is performed by transmitting an electron beam through a cell along an electron beam axis, generating plasma in the cell by energizing a gas with the electron beam, and transmitting an ion beam through the interaction region along an ion beam axis to produce fragment ions. Generating the plasma forms an interaction region in the cell spaced from and not intersecting the electron beam, and including low-energy electrons effective for ECD. The ion beam axis may be at an angle to and offset from the ion beam axis, such that the electron beam does not intersect the ion beam.

Electron capture dissociation (ECD) utilizing electron beam generated low energy electrons

An ion transfer device for transferring ions from one chamber to another, reduced-pressure chamber includes an inlet section and a main capillary section. The inlet section has a lumen and the main capillary section has a bore communicating with the lumen. The inside diameter of the lumen is less than that of the bore. The inlet section may be removable from an installation site separately from the main capillary section. The ion transfer device may be utilized, for example, in an atmospheric-pressure interface of a mass spectrometer.

Ion transfer device for mass spectrometry

A field terminator includes a plurality of electrode plates positioned around a guide axis at a radial distance therefrom. The plates generate a quadrupole DC field such that a polarity on each plate is opposite to a polarity on the plates adjacent thereto. The plates may be positioned at an axial end of a quadrupole ion guide such as a mass filter. In addition to an RF field, the ion guide may generate a quadrupole DC field. The DC field of the plates may be opposite in polarity to that of the ion guide.

Thin field terminator for linear quadrupole ion guides, and related systems and methods

An ion guide generates a first RF field of Nth order where N is an integer equal to or greater than 2, and a second RF field of 2Nth order superimposed on the first RF field. The first and second RF fields may be generated by respective first and second sets of electrodes. Another ion guide may include a converging entrance section followed by an exit section. The converging section may have a hyperbolic profile. A hyperbolic profile may be presented by electrodes having a twisted configuration relative to an ion guide axis.

Dual field multipole converging ion guides, hyperbolic ion guides, and related methods

An electron capture dissociation (ECD) apparatus includes a plasma source for generating plasma. Analyte ions are exposed to the plasma in an ECD interaction region, either inside or outside the plasma source. The apparatus may include one or more devices for refining the plasma in preparation for interaction with the analyte ions. Refining may entail removing unwanted species from the plasma, such as photons, metastable particles, neutral particles, and/or high-energy electrons unsuitable for ECD, and/or controlling a density of low-energy electrons in the plasma.

Plasma-based electron capture dissociation (ECD) apparatus and related systems and methods

An ion trap includes a trap exit at which an ion energy adjusting device is located. The adjusting device may be configured for focusing a beam of ions ejected from the trap, reducing the energy distribution of the ions, and/or reducing the average kinetic energy of the ions. The adjusting device may include lenses to which RF and/or DC voltages are applied.

Adjusting energy of ions ejected from ion trap

A mass spectrum is acquired by accumulating parent ions in an ion trap, ejecting parent ions of a selected m/z ratio into a collision cell, producing fragment ions from the parent ions, and analyzing the fragment ions in a mass analyzer. The other parent ions remain stored in the ion trap, and thus the process may be repeated by mass-selectively scanning parent ions from the ion trap. In this manner, the full mass range of parent ions or any desired subset of the full mass range may be analyzed without significant ion loss or undue time expenditure. The collision cell may provide a large ion acceptance aperture and relatively smaller ion emission aperture. The collision cell may pulse ions out to the mass analyzer. The mass analyzer may be a time-of-flight analyzer. The timing of pulsing of ions out from the collision cell may be matched with the timing of pulsing of ions into the time-of-flight analyzer.

Systems and methods for MS-MS-analysis

A time-of-flight mass spectrometer (TOF MS) includes an ion gate, an ion guide downstream of the ion gate, and a TOF analyzer downstream of the ion guide. The TOF MS is operated with an adjustable duty cycle to limit the amount of ions entering a TOF analyzer and avoid saturating a detector system of the TOF MS. The duty cycle is adjusted by controlling the ion gate. The ion guide emits ions as a continuous beam, without trapping the ions. The ion guide may be operated as a collision cell. The TOF MS may also include a mass filter upstream of the ion guide.

Controlling ion flux into time-of-flight mass spectrometers

An ion processing apparatus includes a plurality of electrodes, first and second insulators, a housing, and a plurality of compliant first supports and second supports. Each electrode has a length along a central axis, and includes a first end region and an axially opposing second end region. The first and second insulators are coaxially disposed about the first and second end regions, respectively. The housing is coaxially disposed about the electrodes, the first insulator and the second insulator. The first supports extend between, and into contact with, the first insulator and the housing. The second supports extend between, and into contact with, the second insulator and the housing. The supports isolate the electrodes from external forces.

Linear ion processing apparatus with improved mechanical isolation and assembly

A desired ion is isolated in an ion trapping volume by applying an ion isolation signal to a plurality of ions in the ion trapping volume, including the desired ion to be retained in the ion trapping volume and an undesired ion to be ejected from the ion trapping volume. The ion isolation signal includes a plurality of signal components spanning a frequency range. The plurality of signal components includes a first component having a frequency near a secular frequency of the desired ion, and an adjacent component having a frequency adjacent to the frequency of the first component. The first component has an amplitude greater than the amplitude of the adjacent component.

High-resolution ion isolation utilizing broadband waveform signals

In some embodiments, a method of optimizing operating parameters of an analytical instrument (e.g. lens voltages of a mass spectrometer) includes steps taken to minimize the method duration in the presence of substantial instrument noise and/or drift. Some methods include selecting a best point between a default instrument parameter set (vector) and a most-recent optimum parameter set; building a starting simplex at the selected best point location in parameter-space; and advancing the simplex to find an optimal parameter vector. The best simplex points are periodically re-measured, and the resulting readings are used to replace and/or average previous readings. The algorithm convergence speed may be adjusted by reducing simplex contractions gradually. The method may operate using all-integer parameter values, recognize parameter values that are out of an instrument range, and operate under the control of the instrument itself rather than an associated control computer.

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Concord, CA, United States of America

Kenneth R Newton