Abstract: A method of mass spectrometry is disclosed comprising performing a plurality of experimental runs, wherein each experimental run comprises: periodically mass analysing fragment or product ions at a plurality of time intervals, wherein a delay time is provided between the start of the experimental nm and the first time interval at which the fragment or product ions are mass analysed. Different delay times are provided in different ones of the experimental runs and fragment or product ions that have been analysed in the same time interval in at least one of said experimental runs and that have been analysed in different time intervals in at least one other of said experimental runs are identified as fragment or product ions of interest. These fragment or product ions are thus determined to relate to different precursor ions and are used to identify their respective precursor ions.

Abstract: A method of mass spectrometry is disclosed comprising: a) providing temporally separated precursor ions; b) mass analyzing separated precursor ions, and/or product ions derived therefrom, during a plurality of sequential acquisition periods, wherein the value of an operational parameter of the spectrometer is varied during the different acquisition periods; c) storing the spectral data obtained in each acquisition period along with its respective value of the operational parameter; d) interrogating the stored spectral data and determining which of the spectral data for a precursor ion or product ions meets a predetermined criterion, and determining the value of the operational parameter that provides this mass spectral data as a target operational parameter value; and e) mass analyzing again the precursor or product ions whilst the operational parameter is set to the target operational parameter value.

Abstract: An ion detection system is disclosed that comprises one or more first devices 11 configured to produce secondary electrons in response to incident ions. The one or more first devices 11 comprise a first ion collection region and a second ion collection region and are configured to produce first secondary electrons in response to one or more ions incident at the first ion collection region and to produce second secondary electrons in response to one or more ions incident at the second ion collection region. The ion detection system also comprises a first output device 14 configured to output a first signal in response to first secondary electrons produced by the one or more first devices 11 and a second output device 15 configured to output a second signal in response to second secondary electrons produced by the one or more first devices 11.

Abstract: A method of mass spectrometry is disclosed comprising: performing a plurality of cycles of operation during a single experimental run, wherein each cycle comprises: mass selectively transmitting precursor ions of a single mass, or range of masses, through or out of a mass separator or mass filter at any given time, wherein the mass separator or mass filter is operated such that the single mass or range of masses transmitted therefrom is varied with time; and mass analysing ions.

Abstract: There is provided a method comprising separating a first population of ions according to a first physico-chemical property in a first separation device, and separating one or more groups of ions emerging from the first separation device in a drift tube and sampling each group of ions using the drift tube to determine the collision cross section of ions in each group of ions, wherein each group of ions corresponds to a range of the first physico-chemical property. The drift tube is configured such that multiple groups of ions in the first population of ions can be sampled by the drift tube in a single cycle of separation of the first separation device. The step of sampling each group of ions comprises determining the mobility of ions in each group of ions by measuring their drift time through the drift tube, and determining the collision cross section of the ions in each group of ions using the determined mobility.

Abstract: A method of mass spectrometry is disclosed comprising: performing a plurality of cycles of operation during a single experimental run, wherein each cycle comprises: mass selectively transmitting precursor ions of a single mass, or range of masses, through or out of a mass separator or mass filter at any given time, wherein the mass separator or mass filter is operated such that the single mass or range of masses transmitted therefrom is varied with time; and mass analysing ions.

Abstract: A Time of Flight analyser comprising a flight tube (160) and a reflectron (170), wherein the reflectron comprises a stack of electrodes (172) that are compressed against the flight tube such that they remain parallel to each other under compression.

Abstract: A method of mass and/or ion mobility spectrometry is disclosed that comprises accumulating ions for a first period of time (T1) one or more times so as to form one or more first groups of ions, accumulating ions for a second period of time (T2) one or more times so as to form one or more second groups of ions, wherein the second period of time (T2) is less that the first period of time (T1), analysing the one or more first groups of ions to generate one or more first data sets, analysing the one or more second groups of ions to generate one or more second data sets, and determining whether the one or more first data sets comprise saturated and/or distorted data. If it is determined that the one or more first data sets comprise saturated and/or distorted data, then the method further comprises replacing the saturated and/or distorted data from the one or more first data sets with corresponding data from the one or more second data sets.

Abstract: A method of mass spectrometry or ion mobility spectrometry is disclosed comprising: providing ions towards an ion storage region; selecting a target maximum charge desired to be stored within the ion storage region at any given time; and reducing the ion current passing to the ion storage region such that the ions entering the ion storage region do not cause the total charge within the storage region to rise above said target maximum charge. The step of reducing the ion current passing to the ion storage region comprises: temporally separating the ions according to their ion mobility in an ion mobility separator; and mass filtering the ions according to mass to charge ratio with a mass filter. Said steps of separating and mass filtering the ions result in substantially only target ions having selected combinations of ion mobility and mass to charge ratio being transmitted towards the ion storage region.

Abstract: An ion guide is disclosed comprising a first array of electrodes and a second array of electrodes and one or more apertures or ion exit regions. The first array of electrodes comprises a first plurality of arcuate electrodes arranged in parallel with one another and such that said first plurality of arcuate electrodes at least partially surround said one or more apertures or ion exit regions and/or wherein said second array of electrodes comprises a second plurality of arcuate electrodes arranged in parallel with one another and such that said second plurality of arcuate electrodes at least partially surround said one or more apertures or ion exit regions.

Abstract: An ion detection system is disclosed that comprises one or more first devices (11) configured to produce secondary electrons in response to incident ions. The one or more first devices (11) comprise a first ion collection region and a second ion collection region and are configured to produce first secondary electrons in response to one or more ions incident at the first ion collection region and to produce second secondary electrons in response to one or more ions incident at the second ion collection region. The ion detection system also comprises a first output device (14) configured to output a first signal in response to first secondary electrons produced by the one or more first devices (11) and a second output device (15) configured to output a second signal in response to second secondary electrons produced by the one or more first devices (11).

Abstract: A mass spectrometer is disclosed comprising a first device, a second device and a switch arranged and adapted: (i) to direct ions at a first time T1 to the first device and to substantially prevent ions from entering the second device; and (ii) to direct ions at a second later time T2 to the second device and to substantially prevent ions from entering the first device. At the first time T1 the second device may not be in an operational state to potentially optimally fragment, react, mass filter or otherwise process ions since the second device may be in a process of equilibration, changing state, re-filling, recharging, transition, replenishing, switching voltage or altering an operational parameter.

Abstract: A method of mass spectrometry is disclosed comprising: a) providing temporally separated precursor ions; b) mass analyzing separated precursor ions, and/or product ions derived therefrom, during a plurality of sequential acquisition periods, wherein the value of an operational parameter of the spectrometer is varied during the different acquisition periods; c) storing the spectral data obtained in each acquisition period along with its respective value of the operational parameter; d) interrogating the stored spectral data and determining which of the spectral data for a precursor ion or product ions meets a predetermined criterion, and determining the value of the operational parameter that provides this mass spectral data as a target operational parameter value; and e) mass analyzing again the precursor or product ions whilst the operational parameter is set to the target operational parameter value.

Abstract: 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.

Abstract: A method of mass and/or ion mobility spectrometry is disclosed that comprises accumulating ions for a first period of time (T1) one or more times so as to form one or more first groups of ions, accumulating ions for a second period of time (T2) one or more times so as to form one or more second groups of ions, wherein the second period of time (T2) is less that the first period of time (T1), analysing the one or more first groups of ions to generate one or more first data sets, analysing the one or more second groups of ions to generate one or more second data sets, and determining whether the one or more first data sets comprise saturated and/or distorted data. If it is determined that the one or more first data sets comprise saturated and/or distorted data, then the method further comprises replacing the saturated and/or distorted data from the one or more first data sets with corresponding data from the one or more second data sets.

Abstract: A mass spectrometer is disclosed comprising an ion mobility separator 4 for separating ions according to their ion mobility, one or more first devices or stages arranged upstream of the ion mobility separator and a control system. The control system is arranged and adapted to monitor directly or indirectly the operating environment within the ion mobility separator 4, and to control the operating environment within the ion mobility separator 4 based on the monitoring by controlling one or more gas flows to or within one or more of the one or more first devices or stages.

Abstract: A method is disclosed comprising: trapping ions in an ion trap (40); applying a first force on the ions within the ion trap in a first direction, said force having a magnitude that is dependent upon the value of a physicochemical property of the ions; applying a second force on these ions in the opposite direction so that the ions separate according to the physicochemical property value as a result of the first and second forces; and then pulsing or driving ions out of one or more regions of the ion trap.

Abstract: A method of mass spectrometry is disclosed wherein one or more relatively abundant or intense species of ions in a first population of ions are selectively attenuated so as to form a second population of ions. The total ion current of the second population of ions is then adjusted so that the ion current corresponding to ions which are onwardly transmitted to a mass analyser comprising an ion detector is within the dynamic range of the ion detector.

Abstract: 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.

Abstract: A method of mass spectrometry is disclosed comprising separating ions temporally in a first device 5 and analysing the mass or mass to charge ratio of the ions or of product or fragment ions derived from the ions in a mass or mass to charge ratio analyser 8 disposed downstream of the first device 5. The method further comprises obtaining a first set of drift times for the ions through the first device 5 by measuring ion arrival times and determining the transit time of the ions and/or of the product or fragment ions through one or more intermediate regions or devices 6, 7 disposed between the first device 5 and the mass to charge ratio analyser 8. The method further comprises obtaining a second set of drift times for the ions through the first device 5 by correcting the first set of drift times to account for the determined transit times.