Abstract: A method of mass spectrometry for analyzing a sample within a mass range of interest includes the steps: ionizing the sample to produce a plurality of precursor ions; performing an MS1 scan of the precursor ions comprising mass analyzing the precursor ions across the mass range of interest, to obtain an MS1 mass spectrum of the precursor ions; determining ion intensity values within the MS1 mass spectrum; selecting precursor mass segments within the mass range of interest, and for each precursor mass segment: fragmenting the precursor ions within that precursor mass segment; and performing an MS2 scan of the fragmented ions by: controlling an amount of fragmented ions for that precursor mass segment, based on an intensity value for that precursor mass segment derived from the MS1 spectrum; and mass analyzing the amount of fragmented ions.

Abstract: A mass spectrometer comprises: a first ion optical device in a relatively low gas pressure region; a second ion optical device in a relatively high gas pressure region, the first and second ion optical devices receiving respective RF voltages from respective RF power supplies for generating respective RF fields that confine ions in respective trapping regions of the ion optical devices; and a gas conductance restriction, restricting gas flow from the relatively high gas pressure region to the relatively low gas pressure region, the gas conductance restriction having an aperture to allow ions to pass from the second to the first ion optical device. The first and second RF power supplies are independent to allow the RF voltages for generating the first RF field to have a different amplitude from the RF voltages for generating the second RF field.

Abstract: The present invention relates to an assembly comprising a vacuum chamber and a time-of-flight mass spectrometer wherein the time-of-flight mass spectrometer is contained within the vacuum chamber. The time-of-flight mass spectrometer comprising a first electrode and a second electrode, the second electrode being spaced apart from the first electrode at a distance defining a portion of an ion-flight path therebetween. The assembly further comprising a first support for supporting the first electrode, the first support arranged between an inner surface of the vacuum chamber and the first electrode. The first support is configured to permit relative movement between at least a portion of the inner surface of the vacuum chamber and the first electrode. The inner surface of the vacuum chamber and the first electrode are thermally coupled. The present invention also relates to a multi-reflection time-of-flight mass analyser.

Abstract: 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, pi, 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, pi, for the particular peak should be a maximum purity value.

Abstract: Calibration of a mass spectrometer is described. In one aspect, a mass spectrometer can generate an offset value indicative of the mass difference between the corrected and reference external calibrant ion data. By comparing the offset value to a threshold, a preliminary mass calibration can be modified, or a recalibration of the mass spectrometer is performed.

Abstract: A method of mass spectrometry for analyzing a sample within a mass range of interest includes the steps: ionizing the sample to produce a plurality of precursor ions; performing an MS1 scan of the precursor ions comprising mass analyzing the precursor ions across the mass range of interest, to obtain an MS1 mass spectrum of the precursor ions; determining ion intensity values within the MS1 mass spectrum; selecting precursor mass segments within the mass range of interest, and for each precursor mass segment: fragmenting the precursor ions within that precursor mass segment; and performing an MS2 scan of the fragmented ions by: controlling an amount of fragmented ions for that precursor mass segment, based on an intensity value for that precursor mass segment derived from the MS1 spectrum; and mass analyzing the amount of fragmented ions.

Abstract: 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, pi, 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, pi, for the particular peak should be a maximum purity value.

Abstract: A data independent acquisition method of mass spectrometry for analyzing a sample within a mass range of interest as it elutes from a chromatography system. The method comprises selecting precursor ions within a mass range of interest to be analyzed, performing at least one MS1 scan of the precursor ions using a first, high-resolution mass analyzer and performing a set of MS2 scans by segmenting the precursor ions into a plurality of precursor mass segments, each precursor mass segment having a mass range of no greater than 5 amu, and for each precursor mass segment fragmenting the precursor ions within that precursor mass segment and performing an MS2 scan of the fragmented ions using a time of flight mass analyzer.

Abstract: A data independent acquisition method of mass spectrometry for analyzing a sample within a mass range of interest as it elutes from a chromatography system. The method comprises selecting precursor ions within a mass range of interest to be analyzed, performing at least one MS1 scan of the precursor ions using a first, high-resolution mass analyzer and performing a set of MS2 scans by segmenting the precursor ions into a plurality of precursor mass segments, each precursor mass segment having a mass range of no greater than 5 amu, and for each precursor mass segment fragmenting the precursor ions within that precursor mass segment and performing an MS2 scan of the fragmented ions using a time of flight mass analyzer.

Abstract: Calibration of a mass spectrometer is described. In one aspect, a mass spectrometer can generate an offset value indicative of the mass difference between the corrected and reference external calibrant ion data. By comparing the offset value to a threshold, a preliminary mass calibration can be modified, or a recalibration of the mass spectrometer is performed.

Abstract: A data independent acquisition method of mass spectrometry for analyzing a sample within a mass range of interest as it elutes from a chromatography system. The method comprises selecting precursor ions within a mass range of interest to be analyzed, performing at least one MS1 scan of the precursor ions using a Fourier Transform mass analyser and performing a set of MS2 scans by segmenting the precursor ions into a plurality of precursor mass segments, each precursor mass segment having a mass range of no greater than 5 amu, and for each precursor mass segment fragmenting the precursor ions within that precursor mass segment and performing an MS2 scan of the fragmented ions.

Abstract: A data independent acquisition method of mass spectrometry for analyzing a sample within a mass range of interest as it elutes from a chromatography system. The method comprises selecting precursor ions within a mass range of interest to be analyzed, performing at least one MS1 scan of the precursor ions using a Fourier Transform mass analyser and performing a set of MS2 scans by segmenting the precursor ions into a plurality of precursor mass segments, each precursor mass segment having a mass range of no greater than 5 amu, and for each precursor mass segment fragmenting the precursor ions within that precursor mass segment and performing an MS2 scan of the fragmented ions.

Abstract: The invention provides a data acquisition system and method for detecting ions in a mass spectrometer, comprising: a detection system for detecting ions comprising two or more detectors for outputting two or more detection signals in separate channels in response to ions arriving at the detection system; and a data processing system for receiving and processing the detection signals in separate channels of the data processing system and for merging the processed detection signals to construct a mass spectrum; wherein the processing in separate channels comprises removing noise from the detection signals by applying a threshold to the detection signals. The detection signals are preferably produced in response to the same ions, the signals being shifted in time relative to each other. The invention is suitable for a TOF mass spectrometer.

Abstract: A technique for time interval measurement is provided. First and second signal components are received, sampled and digitized. The first signal component is derived from a trigger signal that causes or indicates generation 5 of the second signal component. A time interval between the first and second signal components is determined based on a reference time defined by the sampled and digitized first signal component and based on a reference time defined by the sampled and digitized second signal component.

Abstract: A technique for time interval measurement is provided. First and second signal components are received, sampled and digitized. The first signal component is derived from a trigger signal that causes or indicates generation 5 of the second signal component. A time interval between the first and second signal components is determined based on a reference time defined by the sampled and digitized first signal component and based on a reference time defined by the sampled and digitized second signal component.

Abstract: A method of separating charged particles using an analyzer is provided, the method comprising: causing a beam of charged particles to fly through the analyzer and undergo within the analyzer at least one full oscillation in the direction of an analyzer axis (z) of the analyzer whilst orbiting about the axis (z) along a main flight path; constraining the arcuate divergence of the beam as it flies through the analyzer; and separating the charged particles according to their flight time. An analyzer for performing the method is also provided. At least one arcuate focusing lens is preferably used to constrain the divergence, which may comprise a pair of opposed electrodes located either side of the beam.

Abstract: A multi reflection time of flight (MRTOF) mass spectrometer (12) And method for identifying a sample is disclosed. Sample ions are generated at an ion source (15). The MRTOF is a closed mirror arrangement with first and second opposed ion mirrors (20, 20?) on an axis of reflection (XX?). The MRTOF (12) also includes a bidirectional ion deflector (50) on that axis (XX?). The deflector (50) deflects ions onto the reflection axis as a short pulse at time to <zero> where they oscillate multiple times, separating in time of flight according to ion m/z. At a later time t, ions travelling in both directions along the axis (XX?) are ejected out of the MRTOF (12) by the bidirectional deflector (50) to an ion detector arrangement (55). The separation of ions in time of flight allows a “fingerprint” of a biological sample to be produced by the detector arrangement (55) without the need to assign a mass to each peak. Comparison with a library of fingerprints permits identification.

Abstract: A method and apparatus for high resolution separation of ions based on their high field and low-field mobility properties is described. An elongate ion separation channel is defined by a plurality of channel walls. First and second channel walls have first and second spaced ion separation electrode assemblies respectively. A power supply applies a periodic asymmetric potential to one or both of the electrode assemblies so as to generate a periodically asymmetric electric field in the channel for ion mobility separation. The channel walls define an ion separation channel of substantially helical shape.

Abstract: A method of increasing ion throughput within an accumulator, an energy lift and a pulsed ion extractor, operated in that order upon a batch of ions, comprising the steps of: firstly loading a batch of ions into the accumulator; secondly changing the electrical potential of the energy lift to raise the energy of the batch of ions contained therein; and thirdly ejecting the batch of ions from the pulsed ion extractor; and wherein: the energy lift is a separate device from the accumulator and the pulsed ion extractor, and whilst changing the electrical potential in the second step a fresh batch of ions is loaded into the accumulator and/or a previous batch of ions is prepared for ejection in the pulsed ion extractor; or the energy lift is incorporated into the pulsed ion extractor and whilst changing the electrical potential in the second step a fresh batch of ions is loaded into the accumulator; or the energy lift is incorporated into the accumulator and whilst changing the electrical potential in the second st

Abstract: Methods and analysers useful for time of flight mass spectrometry are provided.