Abstract:
A non-linear ion guide is disclosed comprising a plurality of electrodes. An ion guiding region is arranged between the electrodes, and the ion guiding region curves at least in a first direction. A DC voltage is applied to at least some of the electrodes in order to form a DC potential well which acts to confine ions within the ion guiding region in the first direction.
Abstract:
A mass spectrometer is disclosed comprising a first storage ion trap arranged upstream of a high performance analytical ion trap. According to an embodiment ions are simultaneously scanned from both the first and second ion trap. At any instant in time the quantity of charge present within the second ion trap is limited or restricted so that the second ion trap does not suffer from space charge saturation effects and hence the performance of the second ion trap is not degraded.
Abstract:
An ion-ion reaction cell is provided comprising a plurality of electrodes forming an ion guide. A transient DC voltage wave is applied to the electrodes in order to load reagent anions into the ion guide. Analyte cations are then subsequently transmitted through the ion-ion reaction cell by a subsequent transient DC voltage wave. Ion are arranged to undergo ion-ion reactions within the reaction cell and the resulting fragment ions which are formed within the reaction cell are then subsequently translated out of the reaction cell by means of a transient DC voltage wave.
Abstract:
A method of mass spectrometry is disclosed wherein voltage signals from an ion detector are analyzed. A second differential of each voltage signal is obtained and the start and end times of observed voltage peaks are determined. The intensity and average time of each voltage peak is then determined and the intensity and time values are stored. An intermediate composite mass spectrum is then formed by combining the intensity and time values which relate to each voltage peak observed from multiple experimental runs. The various pairs of time and intensity data are then integrated to produce a smooth continuum mass spectrum. The continuum mass spectrum may then be further processed by determining the second differential of the continuum mass spectrum. The start and end times of mass peaks observed in the continuum mass spectrum may be determined. The intensity and mass to charge ratio of each mass peak observed in the continuum mass spectrum may then determined. A final discrete mass spectrum comprising just of an intensity value and mass to charge ratio per species of ion may then be displayed or output.
Abstract:
A mass spectrometer is disclosed comprising an Electron Transfer Dissociation device comprising an ion guide. A control system determines the degree of fragmentation and charge reduction of precursor ions within the ion guide and varies the speed at which ions are transmitted through the ion guide in order to optimise the fragmentation and charge reduction process.
Abstract:
An ion-ion reaction cell is provided comprising a plurality of electrodes (1) forming an ion guide (2). A transient DC voltage wave is applied to the electrodes (2) in order to load reagent anions into the ion guide (2). Analyte cations are then subsequently transmitted through the ion-ion reaction cell by a subsequent transient DC voltage wave. Ion are arranged to undergo ion-ion reactions within the reaction cell and the resulting fragment ions which are formed within the reaction cell are then subsequently translated out of the reaction cell by means of a transient DC voltage wave.
Abstract:
A method of mass spectrometry is disclosed comprising performing a first analysis of a sample of ions wherein one or more parameters are scanned and/or ions are sorted according to one or more parameters during the first analysis. One or more ranges of interest of the one or more parameters from the first analysis are then automatically determined. A second subsequent analysis of the sample of ions is then automatically performed, wherein the second analysis is restricted to one or more of the ranges of interest of the one or more parameters.
Abstract:
An ion guide is disclosed comprising a plurality of electrodes. A first device is arranged and adapted to apply a RF voltage to at least some of the electrodes in order to form, in use, a pseudo-potential well which acts to confine ions in a first direction within the ion guide. A second device is arranged and adapted to apply a DC voltage to at least some of the electrodes in order to form, in use, a DC potential well which acts to confine ions in a second direction within the ion guide. A third device is arranged and adapted to cause ions having desired or undesired mass to charge ratios to be mass to charge ratio selectively ejected from the ion guide in the second direction.
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 vapor may be provided through the tubular electrode (14) which is then subsequently ionized 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 wherein an ion signal is split into a first and second signal. The first and second signals are multiplied by different gains and are digitised. Arrival time and intensity pairs are calculated for both digitised signals and the resulting time and intensity pairs are combined to form a high dynamic range spectrum. The spectrum is then combined with other corresponding spectra to form a summed spectrum.