The present disclosure provides a gas analysis device and a method for detecting sample gas. The gas analysis device includes: an ion mobility spectrometer including an ion mobility tube, an ion gate, a plurality of electrodes, a suppression grid, and a Faraday plate sequentially disposed in the ion mobility tube, wherein the Faraday plate is configured to receive sample ions discharged from the suppression grid, and the Faraday plate is provided with a through hole; a mass spectrometer; a gate valve disposed between the Faraday plate and an ion inlet of the mass spectrometer; and a controller configured to control an opening or closing of the gate valve to allow the sample ions discharged from the suppression grid to flow into the mass spectrometer through the through hole of the Faraday plate when the gate valve is opened.

Pole electrodes (150) are disclosed for use in an ion reaction apparatus, e.g., an electron induced dissociation cell, to reduce fouling due to polymer build-up and increase the useful lifetime of such electrodes. To reduce fouling, the novel pole electrode designs include a X-shaped aperture (160) in lieu of the conventional central circular aperture. The pole electrodes are particularly useful in systems having a plurality of branched electrodes (152) defining a first axis for controlled passage of charged ions and a transverse axis for passage of an electron beam. The pole electrodes are adapted for disposition between an electron source and the branched electrodes to provide an aperture for passage of an electron beam while also impeding escape of ions and reaction products from the apparatus. The X-shaped aperture eliminates or reduces the portion of the pole electrode surface that is most prone to fouling by polymeric build-up.

A mass spectrometry method comprises: (1) introducing ions and gas into an first electrode section of an ion transport apparatus through a slot of an ion transfer tube, the ion tunnel section comprising a first longitudinal axis that is contained within a slot plane of the ion transfer tube, the first longitudinal axis not intersecting an outlet of the ion transfer tube, wherein the apparatus further comprises: (a) a second electrode section configured to receive the ions from the first electrode section and comprising a second longitudinal axis that is not coincident with the first longitudinal axis; and (b) an ion outlet aperture; (2) providing voltages to electrodes of the ion transport apparatus that urge the ions to migrate towards the first longitudinal axis within the first electrode section; and (3) exhausting gas through a port that is offset from the ion outlet aperture.

Disclosed is a method for analytically measuring sample material deposited on a sample support surface, comprising: (a) defining a plurality of regions on the surface, several of which are in contact with sample material, (b1) sampling sections of sample on a region using a desorbing beam to generate desorbed molecules, which are ionized and transferred to an analyzer, (b2) in so doing, sweeping the region by changing an orientation setting of the beam relative to the surface along a non-rectilinear trajectory on the region selected from a plurality of predefined, non-rectilinear trajectories while keeping the support in one position, (c) transitioning from a swept region to a region to be swept next using spatial adjustment of the support, and (d) repeating steps (b1), (b2), and (c) until a predetermined termination condition is fulfilled. A system for analyzing ions, having an ion generation device and a control unit is also disclosed.

The present invention generally provides, in various embodiments, improved methods of analyzing proteins utilizing liquid chromatography and tandem mass spectroscopy (LC-MS/MS), such as by multiplexing samples and using data-independent acquisition.

A method of introducing and ejecting ions from an ion entry/exit device (4) is disclosed. The ion entry/exit device (4) has at least two arrays of electrodes (20,22). The device is operated in a first mode wherein DC potentials are successively applied to successive electrodes of at least one of the electrode arrays ((20,22) in a first direction such that a potential barrier moves along the at least one array in the first direction and drives ions into and/or out of the device in the first direction. The device is also operated in a second mode, wherein DC potentials are successively applied to successive electrodes of at least one of the electrode arrays (20,22) in a second, different direction such that a potential barrier moves along the array in the second direction and drives ions into and/or out of the device in the second direction. The device provides a single, relatively simple device for manipulating ions in multiple directions. For example, the device may be used to load ions into or eject ions from an ion mobility separator in a first direction, and may then be used to cause ions to move through the ion mobility separator in the second direction so as to cause the ions to separate.

A precursor ion selection processing unit (22) sequentially selects precursor ions having different mass-to-charge ratios, and causes an MS/MS spectrum data acquisition processing unit (23) to acquire MS/MS spectrum data corresponding to each precursor ion. The precursor ion selection processing unit (22) sequentially selects the precursor ion having a mass-to-charge ratio which is not included in a predetermined range with respect to a mass-to-charge ratio of the precursor ion for which the MS/MS spectrum data has already been acquired.

A method of determining one or more interference parameters for a particular peak of an isotopic distribution corresponding to a precursor molecule in MS scan data is provided. The MS scan data comprises a plurality of peaks. Each peak has a mass-to-charge ratio and a relative abundance. The isotopic distribution comprises a subset of the plurality of peaks. The one or more interference parameters comprises a peak purity, p.sub.i, for the particular peak. The method comprises determining that there are no interfering peaks relevant to the isotopic distribution and determining that the peak purity, p.sub.i, for the particular peak should be a maximum purity value. Alternatively, the method comprises identifying one or more interfering peaks from the MS scan data, wherein the one or more interfering peaks do not belong to the subset of peaks of the isotopic distribution, and determining the peak purity, p.sub.i, for the particular peak based on: the relative abundance, I.sub.i, of the particular peak, and the relative abundance of the one or more interfering peaks.

An ion-mobility spectrometer system includes a housing with an upstream end, a downstream end, and a drift region defined along a longitudinal axis through the housing between the upstream and downstream ends. A first ionizer is operatively connected the housing to supply ions at the upstream end. A second ionizer is operatively connected to the housing to supply ions at the upstream end, wherein the first and second ionizers are both situated upstream of the drift zone relative to an ion flow path through the drift zone. An electric field generator is operatively connected to the housing to drive ions through the drift zone in a direction from the upstream end toward the downstream end. The second ionizer is a radioactive ionizer mounted to the housing at the upstream end positioned to direct irradiated ions into the housing.

A sample support is a sample support for sample ionization, including: a substrate formed with a plurality of through holes opening to a first surface and a second surface on a side opposite to the first surface; a conductive layer provided not to block the through hole in the first surface; and a reinforcement member disposed inside a part of the plurality of through holes.