Abstract:
A mass spectrometer is disclosed comprising a first ion trap or ion guide (2), a single ion mobility spectrometer or separator stage (3) and a second ion trap or ion guide (4) arranged downstream of the ion mobility spectrometer or separator (3). In a mode of operation ions from the second ion trap or ion guide (4) are passed from the second ion trap or ion guide back upstream to the ion mobility spectrometer or separator (3).
Abstract:
A mass spectrometer is disclosed comprising an ion mobility spectrometer and an ion gate. A collision cell is arranged downstream of the ion gate. The operation of the ion mobility spectrometer and the ion gate are synchronised so that only ions having a particular mass to charge ratio and a desired charge state are onwardly transmitted to the collision cell.
Abstract:
A mass spectrometer is disclosed comprising a Time of Flight mass analyzer comprising an ion detector comprising an Analog to Digital Converter. Signals from the Analog to Digital Converter are digitized and the arrival time and intensity of ions are determined. The arrival time T0 and intensity S0 of each ion arrival event is converted into two separate intensities S(n),S(n+i) which are stored in neighboring time bins T(n), T(n+1).
Abstract:
A mass spectrometer includes an ion mobility spectrometer or separator arranged upstream of a collision or fragmentation cell. Ions are separated according to their ion mobility within the ion mobility spectrometer or separator. The kinetic energy of the ions exiting the ion mobility spectrometer or separator is increased substantially linearly with time in order to optimize the fragmentation energy of ions as they enter the collision or fragmentation cell. During the time that the potential of the ion mobility spectrometer or separator is being varied, the potential of ion-optical components upstream of the ion mobility spectrometer or separator such as an ion source, ion guide, quadrupole mass filter, optional second collision or fragmentation cell and an ion trapping device are kept constant.
Abstract:
An ion guide is disclosed comprising one or more layers of intermediate planar, plate or mesh electrodes. A first array of first electrodes is provided on a upper surface and a second array of second electrodes is arranged on a lower surface. An ion guiding region is formed within the ion guide. One or more transient DC voltages or potentials are preferably applied to the first and second array of second electrodes in order to urge, propel, force or accelerate ions through or along the ion guide.
Abstract:
A mass spectrometer is disclosed comprising a mass selective ion trap or mass analyzer arranged upstream of an ion guide. Ions are scanned out of the mass selective ion trap or mass analyzer and are received in one or more axial potential wells created or formed within the ion guide. One or more transient DC voltages or potentials are preferably applied to the ion guide in order to create a plurality of axial potential wells which are translated along the length of the ion guide. Ions are released in packets from the exit of the ion guide and are orthogonally acceleration into a drift or flight region of an orthogonal acceleration Time of Flight mass analyzer with a relatively high duty cycle.
Abstract:
An ion inlet for a mass spectrometer is disclosed comprising a housing having a sampling orifice and an atmospheric pressure orifice. One or more gas outlets are provided in the housing. Gas is drawn through the sampling orifice by a pump so that the gas exits via the one or more gas outlets.
Abstract:
A mass spectrometer is disclosed comprising a liquid chromatography device for separating ions. A gas phase ion-neutral reaction device is arranged downstream to perform a gas phase ion-neutral reaction such as Hydrogen-Deuterium exchange. A control system is arranged to automatically and repeatedly switch the reaction device back and forth between a first mode of operation and a second mode of operation, wherein in the first mode of operation at least some parent or precursor ions are caused to react within the reaction device and wherein in the second mode of operation substantially fewer or no parent or precursor ions are caused to react.
Abstract:
A mass spectrometer is disclosed comprising a glow discharge device within the initial vacuum chamber of the mass spectrometer. The glow discharge device may comprise a tubular electrode (14) located within an isolation valve (15) which is provided in the vacuum chamber. Reagent vapour may be provided through the tubular electrode (14) which is then subsequently ionised by the glow discharge. The resulting reagent ions may be used for Electron Transfer Dissociation of analyte ions generated by an atmospheric pressure ion source. Other embodiments are contemplated wherein the ions generated by the glow discharge device may be used to reduce the charge state of analyte ions by Proton Transfer Reaction or may act as lock mass or reference ions.
Abstract:
A mass spectrometer is disclosed comprising a device (2) which is operable in a first mode of operation to separate ions temporally according to their ion mobility by applying a continuous axial electric field. The device (2) is also operable in a second mode of operation wherein ions are separated temporally according to the their mass to charge ratio by pulsing an applied axial electric field ON and OFF.