Abstract: A hybrid mass spectrometer design and architecture, and methods of operating mass spectrometers are disclosed. According to one operating method, an analysis time is determined for each one of a plurality of ion species to be analyzed in an ordered sequence, and an injection time is calculated for at least some of the ion species based on an analysis time of a preceding ion species in the ordered list. The method enables more efficient utilization of analyzer time.

Abstract: A mass spectrometer includes a radio frequency ion trap; and a controller. The controller is configured to cause an ion population to be injected into the radio frequency ion trap; supply a first isolation waveform to the radio frequency ion trap for a first duration, and supply a second isolation waveform to the radio frequency ion trap for a second duration. The first isolation waveform has at least a first wide notch at a first mass-to-charge ratio, and the second isolation waveform has at least a first narrow notch at the first mass-to-charge ratio. The first and second isolation waveforms are effective to isolate one or more precursor ions from the ion population.

Abstract: A mass spectrometer includes a radio frequency ion trap; and a controller. The controller is configured to cause an ion population to be injected into the radio frequency ion trap; supply a first isolation waveform to the radio frequency ion trap for a first duration, and supply a second isolation waveform to the radio frequency ion trap for a second duration. The first isolation waveform has at least a first wide notch at a first mass-to-charge ratio, and the second isolation waveform has at least a first narrow notch at the first mass-to-charge ratio. The first and second isolation waveforms are effective to isolate one or more precursor ions from the ion population.

Abstract: A method is disclosed for operating a mass spectrometer having a Fourier Transform (FT) analyzer, such as an orbital electrostatic trap mass analyzer, to avoid peak coalescence and/or other phenomena arising from frequency-shifting caused by ion-ion interactions. Ions of a first group are mass analyzed, for example in a quadrupole ion trap analyzer, to generate a mass spectrum. The estimated frequency shift of the characteristic periodic motion in the FT analyzer is calculated for one or more ion species of interest based on the intensities of adjacent (closely m/z-spaced) ion species. If the estimated frequency shift(s) for the one or more ion species exceeds a threshold, then a target ion population for an FT analyzer scan is adjusted downwardly to a value that produces a shift of acceptable value. An analytical scan of a second ion group is performed at the adjusted target ion population.

Abstract: A method is described for identifying the occurrence and location of charging of ion optic devices arranged along the ion path of a mass spectrometer. The method includes repeatedly performing a sequence of introducing a beam of discharge ions to a location on the ion path, and subsequently measuring the intensities of opposite-polarity sample ions delivered to a mass analyzer, with the discharge ions being delivered to a location further downstream in the ion path at each successive sequence.

Abstract: A method for mass analyzing ions comprising a restricted range mass-to-charge (m/z) ratios comprising (i) performing a survey mass analysis, using a first mass analyzer employing indirect detection of ions by image current detection, to measure a flux of ions having m/z ratios within said range and (ii) performing a dependent mass analysis, using a second mass analyzer, of an optimal quantity of ions having m/z ratios within said range, said optimal quantity collected for a time period determined by the measured ion flux, the method characterized in that: the time period is determined using a corrected ion flux that includes a correction that comprises an estimate of the quantity of ions that are undetected by the first mass analyzer.

Abstract: A hybrid mass spectrometer design and architecture, and methods of operating mass spectrometers are disclosed. According to one operating method, an analysis time is determined for each one of a plurality of ion species to be analyzed in an ordered sequence, and an injection time is calculated for at least some of the ion species based on an analysis time of a preceding ion species in the ordered list. The method enables more efficient utilization of analyzer time.

Abstract: A method is disclosed for operating a mass spectrometer having a Fourier Transform (FT) analyzer, such as an orbital electrostatic trap mass analyzer, to avoid peak coalescence and/or other phenomena arising from frequency-shifting caused by ion-ion interactions. Ions of a first group are mass analyzed, for example in a quadrupole ion trap analyzer, to generate a mass spectrum. The estimated frequency shift of the characteristic periodic motion in the FT analyzer is calculated for one or more ion species of interest based on the intensities of adjacent (closely m/z-spaced) ion species. If the estimated frequency shift(s) for the one or more ion species exceeds a threshold, then a target ion population for an FT analyzer scan is adjusted downwardly to a value that produces a shift of acceptable value. An analytical scan of a second ion group is performed at the adjusted target ion population.

Abstract: A method for mass analyzing ions comprising a restricted range mass-to-charge (m/z) ratios comprising performing a survey mass analysis using a mass analyzer to measure a flux of ions having m/z ratios within said restricted range and performing a dependent mass analysis of an optimal quantity of ions having m/z ratios within said restricted range, said optimal quantity collected for a time period determined by the measured ion flux, CHARACTERIZED IN THAT: the time period is determined using a corrected ion flux that accounts for one or more of: (a) imperfect restriction of collected ions to the range of m/z ratios, (b) inclusion of ions within the range of m/z ratios that are undetected by the survey mass analysis, (c) different mass analyzers used for the dependent and survey mass analyses, and (d) different ion pathways used during dependent and the survey mass analyses.

Abstract: A method for mass analyzing ions comprising a restricted range mass-to-charge (m/z) ratios comprising (i) performing a survey mass analysis, using a first mass analyzer employing indirect detection of ions by image current detection, to measure a flux of ions having m/z ratios within said range and (ii) performing a dependent mass analysis, using a second mass analyzer, of an optimal quantity of ions having m/z ratios within said range, said optimal quantity collected for a time period determined by the measured ion flux, the method characterized in that: the time period is determined using a corrected ion flux that includes a correction that comprises an estimate of the quantity of ions that are undetected by the first mass analyzer.

Abstract: A sample ionization system includes at least an ionization source disposed at an ion source end of a charged particle analyzer, for selectably generating first ions in an analyzing mode of operation and second ions in a cleaning mode of operation. The first ions are one of positively and negatively charged and the second ions are the other one of positively and negatively charged. The second ions are directed through the charged particle analyzer toward a surface of an ion optic component, for at least partially neutralizing a buildup of charge caused by the first ions impinging on the surface of the at least one ion optic component.

Abstract: A mass spectrometry method for analyzing isobarically-labeled analyte compounds comprising (a) ionizing compounds including the isobarically-labeled analyte compounds to generate a plurality of precursor ion species comprising different respective m/z ratios, (b) isolating a precursor ion species, (c) fragmenting the precursor ion species to generate a plurality of first-generation fragment ion species comprising different respective m/z ratios, and (d) selecting and co-isolating two or more of the first-generation product-ion species, the method characterized by: (e) fragmenting all of the selected and isolated first-generation product ion species so as to generate a plurality of second-generation fragment ion species including released label ions; (f) generating a mass spectrum of the second-generation fragment ion species; and (g) generating quantitative information relating to at least one analyte compound based on peaks of the mass spectrum attributable to the released label ions.

Abstract: A method for mass analyzing ions comprising a restricted range mass-to-charge (m/z) ratios comprising (i) performing a survey mass analysis, using a first mass analyzer employing indirect detection of ions by image current detection, to measure a flux of ions having m/z ratios within said range and (ii) performing a dependent mass analysis, using a second mass analyzer, of an optimal quantity of ions having m/z ratios within said range, said optimal quantity collected for a time period determined by the measured ion flux, the method characterized in that: the time period is determined using a corrected ion flux that includes a correction that comprises an estimate of the quantity of ions that are undetected by the first mass analyzer.

Abstract: A mass spectrometry method for analyzing isobarically-labeled analyte compounds comprising (a) ionizing compounds including the isobarically-labeled analyte compounds to generate a plurality of precursor ion species comprising different respective m/z ratios, (b) isolating a precursor ion species, (c) fragmenting the precursor ion species to generate a plurality of first-generation fragment ion species comprising different respective m/z ratios, and (d) selecting and co-isolating two or more of the first-generation product-ion species, the method characterized by: (e) fragmenting all of the selected and isolated first-generation product ion species so as to generate a plurality of second-generation fragment ion species including released label ions; (f) generating a mass spectrum of the second-generation fragment ion species; and (g) generating quantitative information relating to at least one analyte compound based on peaks of the mass spectrum attributable to the released label ions.

Abstract: A method for mass analyzing ions comprising a restricted range mass-to-charge (m/z) ratios comprising performing a survey mass analysis using a mass analyzer to measure a flux of ions having m/z ratios within said restricted range and performing a dependent mass analysis of an optimal quantity of ions having m/z ratios within said restricted range, said optimal quantity collected for a time period determined by the measured ion flux, CHARACTERIZED IN THAT: the time period is determined using a corrected ion flux that accounts for one or more of: (a) imperfect restriction of collected ions to the range of m/z ratios, (b) inclusion of ions within the range of m/z ratios that are undetected by the survey mass analysis, (c) different mass analyzers used for the dependent and survey mass analyses, and (d) different ion pathways used during dependent and the survey mass analyses.

Abstract: A tandem mass spectrometer includes a two-dimensional ion trap that has an elongated ion-trapping region extending along a continuously curving path between first and second opposite ends thereof. The elongated trapping region has a central axis that is defined substantially parallel to the curved path and that extends between the first and second opposite ends. The two-dimensional ion trap is configured for receiving ions through the first end and for mass selectively ejecting the ions along a direction that is orthogonal to the central axis, such that the ejected ions are directed generally toward a common point. The tandem mass spectrometer also includes a collision cell having an ion inlet that is disposed about the common point for receiving the ions that are ejected therefrom and for causing at least a portion of the ions to undergo collisions and form product ions by fragmentation.

Abstract: A method is described for identifying the occurrence and location of charging of ion optic devices arranged along the ion path of a mass spectrometer. The method includes repeatedly performing a sequence of introducing a beam of discharge ions to a location on the ion path, and subsequently measuring the intensities of opposite-polarity sample ions delivered to a mass analyzer, with the discharge ions being delivered to a location further downstream in the ion path at each successive sequence.

Abstract: An ion transport apparatus for a mass- or ion-mobility-spectrometer comprises: (a) a plurality of strip electrodes in a series on a flat substrate; (b) an ion outlet aperture in the substrate disposed adjacent to a first one of the plurality of strip electrodes; (c) a cage electrode at least partially enclosing the plurality of strip electrodes and the ion outlet aperture; (d) a radio frequency (RF) voltage generator operable to supply an RF phase difference between each pair of adjacent electrodes; and (e) at least one DC voltage source operable to supply first and second DC voltages to the cage electrode and an extraction electrode and to supply respective DC bias voltages to each of the plurality of electrodes, wherein electrode strip widths of a series of the plurality of electrodes progressively increase away from the first one of the plurality of electrodes.

Abstract: A method of obtaining and analyzing a mass spectrum of a sample comprising components is characterized by: setting values of a first energy level and a second energy level; chromatographically separating the components; ionizing a portion of the separated components to create precursor ions; introducing a first portion of the precursor ions into a collision or reaction cell and generating a first sub-population of ions corresponding to the first energy level; introducing a second portion of the precursor ions into the cell and generating a second sub-population of ions corresponding to the second energy level; transferring a mixture of the first and second sub-populations of ions into a mass analyzer; producing an analysis of the ions of the mixture; varying the value of at least one of the first and the second energy levels according to a pre-determined cyclical variation; repeating various above steps; and analyzing the time-variation of the analyses.

Abstract: An ion transport apparatus for a mass- or ion-mobility-spectrometer comprises: (a) a plurality of strip electrodes in a series on a fiat substrate; (b) an ion outlet aperture in the substrate disposed adjacent to a first one of the plurality of strip electrodes; (c) a cage electrode at least partially enclosing the plurality of strip electrodes and the ion outlet aperture; (d) a radio frequency (RF) voltage generator operable to supply an RF phase difference between each pair of adjacent electrodes; and (e) at least one DC voltage source operable to supply first and second DC voltages to the cage electrode and an extraction electrode and to supply respective DC bias voltages to each of the plurality of electrodes, wherein electrode strip widths of a series of the plurality of electrodes progressively increase away from the first one of the plurality of electrodes.