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 mass filtering ions is disclosed comprising: providing a first, AC-only, mass filter (2); providing a second mass filter (4) downstream of the first mass filter; applying a first AC voltage (8) to electrodes of the first mass filter so as to radially confine ions between the electrodes, and applying a second AC voltage (10) between electrodes of the first mass filter (2) so as to radially excite some of said ions such that these ions are not transmitted; and using the second mass filter (4) to mass filter ions; wherein at any given time the second mass filter (4) only transmits ions having a first range of mass to charge ratios and filters out all other ions; and wherein the step of applying the at least one second AC voltage (10) to electrodes of the first mass filter (2) radially excites ions such that at least some ions having mass to charge ratios above said first range are not transmitted into the second mass filter.

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 filtering ions is disclosed comprising: providing a first, AC-only, mass filter 2; providing a second mass filter 4 downstream of the first mass filter; applying a first AC voltage 8 to electrodes of the first mass filter so as to radially confine ions between the electrodes, and applying a second AC voltage 10 between electrodes of the first mass filter 2 so as to radially excite some of said ions such that these ions are not transmitted; and using the second mass filter 4 to mass filter ions; wherein at any given time the second mass filter 4 only transmits ions having a first range of mass to charge ratios and filters out all other ions; and wherein the step of applying the at least one second AC voltage 10 to electrodes of the first mass filter 2 radially excites ions such that at least some ions having mass to charge ratios above said first range are not transmitted into the second mass filter.

Abstract: A method of correcting mass spectral data comprises making calibration measurements of first intrinsic components (A, B, C) at one or more calibration times (t1) using calibrants which have known mass to charge ratio (m/z) values or previously mass measured mass to charge ratio (m/z) values, making a list of second intrinsic components (D, E, F) which are present during more than one acquisition periods, wherein the second intrinsic components have mass to charge ratio (m/z) values that were not present or observed during or close to the one or more calibration times (t1) but which do overlap in time with the first intrinsic components (A, B, C), and utilising the list to calculate a mass or mass to charge ratio (m/z) correction factor for one or more acquisition periods which are not close or adjacent in time to an acquisition period containing a directly calibrated mass to charge ratio (m/z) value.

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 operating a quadrupole device (10) is disclosed. A voltage source (12) applies a main quadrupolar voltage, an auxiliary quadrupolar voltage and a dipolar voltage to the quadrupole device (10). This may be done such that only ions corresponding to a single X-band, X-band-like, Y-band or Y-band-like stability region are transmitted by the quadrupole device (10).

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 operating a quadrupole device (10) is disclosed. The quadrupole device (10) is operated in a mode of operation by applying a repeating voltage waveform comprising a main drive voltage and at least one auxiliary drive voltage is applied to the quadrupole device to the quadrupole device (10). The intensity of ions passing into the quadrupole device is varied with time in synchronisation with the repeating voltage waveform. This may be done such that the number of ions per unit phase which initially experience a phase within a first range of phases of the repeating voltage waveform is greater than the number of ions per unit phase which initially experience a phase within a second range of phases of the repeating voltage waveform.

Abstract: An ion-optical device comprising: a plurality of electrodes (2); a first AC voltage supply (6); and a transformer (4) having: a toroidal core (8); a primary winding (10) connected to the AC voltage supply (6) and passing through the aperture within the toroidal core (8); and at least one secondary winding (13,15) wound around the toroidal core 8 and electrically connected to multiple ones of said plurality of electrodes.

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 mass spectrometry comprising the steps of: providing a library of background ion data including m/z data for multiple background ions in respect of different chromatographic conditions including a change of solvent composition from aqueous (1) to organic (3), chromatographically separating a sample containing analyte components, wherein the chromatographic separation is performed under a chromatographic condition in respect of which background ion data is provided in the library, analysing the sample to obtain sample data comprising m/z values for the sample components as a function of retention time (RT), and calculating one or more error values including ppm error as a function of retention time based on a comparison between background ions identified in the sample data and the library of background ion data. Outliers (4), corrupted measurements and inconsistent measurements at specific retention times are rejected.

Abstract: A method of encoding a parent or precursor ion beam to aid product ion assignment is disclosed. According to an embodiment the energy of parent ions entering a collision cell 3 is progressively increased. Different species of parent ions fragment at different collision energies. Fragment ion intensity profiles are matched with parent ion intensity profiles to correlate fragment ions with corresponding parent ions.

Abstract: An instrument for analysing ions is disclosed comprising: a first device (4) configured to onwardly transmit ions having a restricted range of physicochemical property values at any given time, and to change said range with time such that the first device (4) is capable of transmitting ions having different physicochemical property values at different times; and an ion mobility separator (6) arranged to receive ions transmitted by the first device (4); wherein the instrument is configured such that the time that any given ion enters the ion mobility separator (6) and begins to be separated from other ions is defined by its time of transmission by the first device.

Abstract: A method of separating ions is disclosed comprising: providing an ion separation device comprising a plurality of electrodes; providing a gas flow (5) so as to urge ions in a first direction along the device; applying voltages to said electrodes so that a plurality of travelling potentials (4) urge the ions in a second opposite direction; and varying at least one operational parameter of the travelling potentials (4) as a function of position along the device such that ions of different mobility or mass to charge ratio become trapped at different locations along the device.

Abstract: A method of analysing ions is disclosed comprising: (i) subjecting ions of an analyte molecule to different activation levels at different times so as to cause the ions to have different mobilities at said different times, wherein the activation level is varied in a plurality of cycles, and wherein the activation level is varied between said different levels during each of the cycles. The method uses an ion mobility separator or scanned ion mobility filter to determine the mobilities of the ions for said different activation levels; and correlates the determined mobilities with their respective activation levels so as to thereby obtain a fingerprint for the analyte molecule.

Abstract: The present disclosure provides a method comprising providing a sample to be analysed, separating successive populations of ions from said sample in a separator, wherein said populations of ions are introduced into said separator at regular intervals, and the intervals are timed such that at least some ions in a subsequent population of ions overlap ions in a preceding population of ions, varying one or more parameters of said separator such that different populations of ions experience different separation conditions, detecting ions from said populations of ions and obtaining a convolved data set, and de¬ convolving said convolved data set using the known variance of the parameters and outputting data corresponding to the successive populations of 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: A method of mass spectrometry is disclosed in which one or more AC excitation voltage waveforms are applied to electrodes of an ion guide to radially excite and thereby attenuate ions having mass to charge ratios within respective mass to charge ratio windows. The AC excitation voltage waveforms are varied with time such that ions having different mass to charge ratios are attenuated with different attenuation time profiles. Plural AC excitation voltage waveforms may be varied with time to provide unique mass to charge ratio encoding.

Abstract: A method of mass spectrometry is disclosed comprising: a step (10) of analysing a reference compound in a first mass spectrometer and outputting mass spectral data in response thereto; a step (20) of analysing the reference compound in a second, different mass spectrometer and outputting mass spectral data in response thereto; and a step (30) of automatically adjusting an operational parameter, duty cycle (e.g. duty cycle of data acquisition), or acquired spectral data of at least one mass spectrometer such that, for the same (given) consumption of reference compound by the spectrometer, the statistical precision of quantification (the number of detected ions) and/or of mass measurement (the mass resolution) by the mass spectrometer is substantially the same as that of the other mass spectrometer. A similar method of ion mobility spectrometry is disclosed.