Abstract: A transmission window that has a constant rate of precursor ion transmission for each precursor ion is stepped across a mass range, producing a series of overlapping transmission windows across the mass range. The precursor ions produced at each step are fragmented. Resulting product ions are analyzed, producing a product ion spectrum for each step of the transmission window and a plurality of product ion spectra for the mass range. For at least one product ion of the plurality of product ion spectra, a function that describes how an intensity of the at least one product ion from the plurality of product ion spectra varies with precursor ion mass as the transmission window is stepped across the mass range is calculated. A precursor ion of the at least one product ion is identified from the function. An elution profile can also be determined from the function.

Abstract: A sample analysis system having a continuous beam ion mobility filter incorporates an ion removal mechanism for removing residual ions from the ion mobility filter to reduce cross-talk. A sample to be analyzed by the sample analysis system can be entered into the continuous beam ion mobility filter, which filters the ions of the sample and passes the filtered group of ions to a detector or a mass analyzer (e.g., via an ion optics assembly disposed between the mass analyzer and the ion mobility filter), where some or all of the ions in the group are detected. The ion removal mechanism then removes all or a substantial portion of the residual ions from the ion mobility filter that are left over from the first filtered group before a second filtered group is passed through. In some aspects, the ion removal mechanism can be operated concurrent with an ion removal mechanism for removing residual ions from an ion optics assembly.

Abstract: Systems and methods are provided for shaping an effective transmission window used to select precursor ions for a precursor mass range of a sequential windowed acquisition experiment. For at least one precursor mass range, an ion transfer function is selected that is a function of mass using a processor. A quadrupole mass filter that transmits ions from a sample is instructed to produce two or more transmission windows over time using the processor. The two or more transmission windows are produced to cumulatively create an effective transmission window for the at least one precursor mass range with a shape described by the ion transfer function.

Abstract: Ions are separated from a sample over time and filtered. The precursor ions produced at each step are fragmented. Resulting product ions are analyzed using a mass analyzer, producing a product ion spectrum for each step of the transmission window and a plurality of product ion spectra for the mass range for the each scan. The plurality of product ion spectra are received, producing a plurality of multi-scan product ion spectra. At least one product ion is selected from the plurality of multi-scan product ion spectra that is present at least two or more times in product ion spectra from each of two or more scans. A known separation profile of a precursor ion is fit to intensities from the at least one product ion in the plurality of multi-scan product ion spectra to reconstruct a separation profile of a precursor ion of the at least one product ion.

Abstract: A transmission window that has a constant rate of precursor ion transmission for each precursor ion is stepped across a mass range, producing a series of overlapping transmission windows across the mass range. The precursor ions produced at each step are fragmented. Resulting product ions are analyzed, producing a product ion spectrum for each step of the transmission window and a plurality of product ion spectra for the mass range. For at least one product ion of the plurality of product ion spectra, a function that describes how an intensity of the at least one product ion from the plurality of product ion spectra varies with precursor ion mass as the transmission window is stepped across the mass range is calculated. A precursor ion of the at least one product ion is identified from the function. An elution profile can also be determined from the function.

Abstract: Systems and methods are provided for shaping an effective transmission window used to select precursor ions for a precursor mass range of a sequential windowed acquisition experiment. For at least one precursor mass range, an ion transfer function is selected that is a function of mass using a processor. A quadrupole mass filter that transmits ions from a sample is instructed to produce two or more transmission windows over time using the processor. The two or more transmission windows are produced to cumulatively create an effective transmission window for the at least one precursor mass range with a shape described by the ion transfer function.

Abstract: Ions are separated from a sample over time and filtered. The precursor ions produced at each step are fragmented. Resulting product ions are analyzed using a mass analyzer, producing a product ion spectrum for each step of the transmission window and a plurality of product ion spectra for the mass range for the each scan. The plurality of product ion spectra are received, producing a plurality of multi-scan product ion spectra. At least one product ion is selected from the plurality of multi-scan product ion spectra that is present at least two or more times in product ion spectra from each of two or more scans. A known separation profile of a precursor ion is fit to intensities from the at least one product ion in the plurality of multi-scan product ion spectra to reconstruct a separation profile of a precursor ion of the at least one product ion.

Abstract: A method for operating tandem ion traps is provided, involving a) accumulating ions in the first ion trap at a first time; b) transmitting a first plurality of ions out of the first ion trap and into the second ion trap at a second time, the first plurality of ions having masses within a first mass range; c) retaining a second plurality of ions in the first ion trap at the second time, the second plurality of ions having masses within a second mass range different from the first mass range; d) transmitting the first plurality of ions out of the second ion trap at a third time; and, e) transmitting the second plurality of ions out of the first ion trap and into the second ion trap at the third time.

Abstract: A tandem mass spectrometer system and method are described, where a composite voltage waveform is applied to so as to trap ion having selected m/z. The trapped ions may be subject to collision induced ionization dissociation (CID) by a selectable discrete frequency voltage waveform positioned so as to be in a notch in a broadband waveform. The resultant ion products may be trapped using a second notch having a center frequency corresponding to the ion product to be trapped. The process may be repeated so as to increase the amount of ions produced, or the process a first resultant ion product to yield a second resultant in product, which may be trapped.

Abstract: A mass spectrometer having an elongated rod set, the rod set having a first end, a second end, a plurality of rods and a central longitudinal axis is described as is a method operating same.

Abstract: A mass spectrometer system and a method of operating a mass spectrometer are provided. An RF field is produced between the plurality of rods to radially confine the ions in the rod set. The RF field has a resolving DC component field. The resolving DC component field is varied along at least a portion of a length of the rod set to provide a DC axial force acting on the ions.

Abstract: A mass spectrometer having an elongated rod set, the rod set having a first end, a second end, a plurality of rods and a central longitudinal axis is described as is a method operating same.

Abstract: A method for operating tandem ion traps is provided, involving a) accumulating ions in the first ion trap at a first time; b) transmitting a first plurality of ions out of the first ion trap and into the second ion trap at a second time, the first plurality of ions having masses within a first mass range; c) retaining a second plurality of ions in the first ion trap at the second time, the second plurality of ions having masses within a second mass range different from the first mass range; d) transmitting the first plurality of ions out of the second ion trap at a third time; and, e) transmitting the second plurality of ions out of the first ion trap and into the second ion trap at the third time.

Abstract: A mass spectrometer and a method of operating and building same is provided in which a hexapole component is deliberately added to a substantially quadrupole field. This can result in unwanted octopole and dipole fields also being added to the substantially quadrupole field. Modifications to the mass spectrometer as well as ways of operating the mass spectrometer are provided for dealing with the unwanted octopole and dipole fields.

Abstract: A method and apparatus for trapping or guiding ions is provided. The ion trap or ion guide includes a first set of electrodes and a second set of electrodes, the first set of electrodes defining a first portion of an ion channel to trap or guide the introduced ions. In operation, periodic voltages are applied to electrodes in the first set of electrodes to generate a first oscillating electric potential that radially confines the ions in the ion channel, while periodic voltages are applied to electrodes in the second set of electrodes to generate a second oscillating electric potential that axially confines the ions in the ion channel.

Abstract: A mass spectrometer and a method of operating and building same is provided in which a hexapole component is deliberately added to a substantially quadrupole field. This can result in unwanted octopole and dipole fields also being added to the substantially quadrupole field. Modifications to the mass spectrometer as well as ways of operating the mass spectrometer are provided for dealing with the unwanted octopole and dipole fields.

Abstract: A mass spectrometer and a method of operating same is provided. The mass spectrometer has an elongated rod set. The rod set has an entrance end and an exit end. An RF drive voltage is applied to the rod set to radially confine a first group of ions and a second group of ions of opposite polarity in the rod set. An entrance auxiliary RF voltage is applied to the entrance end and an exit auxiliary RF voltage to the exit end relative to the RF drive voltage, to trap both the first group of ions and the second group of ions in the rod set.

Abstract: In the field of mass spectrometry, a method and apparatus for fragmenting ions with a relatively high degree of resolution and efficiency. The technique includes trapping the ions in a linear ion trap, in which the background or neutral gas pressure is preferably on the order of 10-5 Torr. The trapped ions are resonantly excited for a relatively extended period of time, e.g., exceeding 50 ms, at relatively low excitation levels, e.g., less than 1 Volt (0-pk). The technique allows selective dissociation of ions with a high discrimination. High fragmentation efficiency may be achieved by superimposing a higher order multipole field onto the quadrupolar RF field used to trap the ions. The multipole field, preferably an octopole field, dampens the radial oscillatory motion of resonantly excited ions at the periphery of the trap. This reduces the probability that ions will eject radially from the trap thus increasing the probability of collision induced dissociation.

Abstract: A method and apparatus for trapping or guiding ions is provided. The ion trap or ion guide includes a first set of electrodes and a second set of electrodes, the first set of electrodes defining a first portion of an ion channel to trap or guide the introduced ions. In operation, periodic voltages are applied to electrodes in the first set of electrodes to generate a first oscillating electric potential that radially confines the ions in the ion channel, while periodic voltages are applied to electrodes in the second set of electrodes to generate a second oscillating electric potential that axially confines the ions in the ion channel.

Abstract: A mass spectrometer system and a method of operating a mass spectrometer are provided. An RF field is produced between the plurality of rods to radially confine the ions in the rod set. The RF field has a resolving DC component field. The resolving DC component field is varied along at least a portion of a length of the rod set to provide a DC axial force acting on the ions.