Abstract: Methods for acquiring mass spectral data comprise determining first and second sets of m/z sub-ranges comprising respective first and second m/z sub-ranges. A sample is mass filtered to isolate ions in the first and second sets of m/z sub-ranges using respective mass filters. Mass analysis is performed to obtain first and second partial mass spectral data sets, the first and second mass filters having first and second response profiles having respective relatively high transmission regions and one or more relatively low transmission regions. The first and second sets of m/z sub-ranges are determined such that relatively high transmission regions of the first response profile and the second response profile at least partially overlap.

Abstract: Methods for acquiring mass spectral data of a sample across at least a portion of an m/z range comprise receiving mass spectral data across the m/z range and partitioning the m/z range into one or more sets of m/z sub-ranges, each set comprising one or more m/z sub-ranges, by dividing the m/z range into a plurality of m/z bins, determining an indication of ion abundance for each m/z bin, based on the mass spectral data, and forming an m/z sub-range of the one or more sets of m/z sub-ranges by assigning m/z bins having ion abundances that correspond to at least a threshold degree to the formed m/z sub-range. A mass analysis is performed on the sample for each set of m/z sub-ranges, thereby acquiring one or more partial mass spectral data sets.

Abstract: Methods for acquiring mass spectral data of a sample across at least a portion of an m/z range include receiving mass spectral data of the sample across the m/z range. The m/z range is partitioned into one or more sets of m/z sub-ranges, each set comprising one or more m/z sub-ranges, by dividing the m/z range into a plurality of m/z bins, determining an indication of ion abundance for each m/z bin, based on the mass spectral data, and forming an m/z sub-range of the one or more sets of m/z sub-ranges by assigning m/z bins having ion abundances that correspond to at least a threshold degree to the formed m/z sub-range. A mass analysis is performed on the sample for each set of m/z sub-ranges, thereby acquiring one or more partial mass spectral data sets.

Abstract: A Time of Flight (TOF) mass analyser comprises an ion source, a detector, an electrode, and a resistive divider comprising first and second resistors. The ion source and the detector define an ion flight path from the ion source to the detector. The electrode is arranged along the ion flight path and receives an output voltage. Thermal expansion produces a first mass shift/Kelvin of detected ions. The resistive divider is thermally coupled to the TOF mass analyser to receive an input voltage and output an output voltage to the electrode. The first and second resistors have respective first and second temperature coefficients that provide a voltage shift/Kelvin to the output voltage to the electrode producing a second mass shift/Kelvin of detected ions, compensating for the first mass shift/Kelvin.

Abstract: A method of optical spectroscopy for analysing a sample using an optical spectrometer is provided. The method comprises obtaining a sample spectrum of the sample using the optical spectrometer and obtaining a blank spectrum using the optical spectrometer. The blank spectrum comprises structured background radiation which is correlated with the sample spectrum. A cross-correlation of the sample spectrum and the blank spectrum is determined. A mapped blank spectrum is generated by mapping the blank spectrum to the sample spectrum based on the cross-correlation, and the mapped blank spectrum is subtracted from the sample spectrum to generate a background corrected sample spectrum.

Abstract: An isotope ratio mass spectrometer has an ion source, a static field mass filter, a reaction cell to induce a mass shift reaction, and a sector field mass analyser for spatially separating ions from the reaction cell according to their m/z. A detector platform detects a plurality of different ion species separated by the sector field mass analyser. The static field mass filter has a first Wien filter that deflects ions away from a longitudinal symmetry axis of the spectrometer in accordance with the ions' m/z, and a second Wien filter that deflects ions back towards the longitudinal symmetry axis in accordance with the ions' m/z. An inverting lens is positioned along the longitudinal axis between the Wien filters to invert the direction of deflection of the ions from the first Wien filter. The static field mass filter provides high transmission and improved spectrometer sensitivity. The first and second Wien filters permit simple tuning.

Abstract: A conversion circuit is arranged for converting an ion detection current (id) produced by an ion detector into an ion detection signal (P). The conversion circuit comprises an input stage for converting the ion detection current (id) into an ion detection voltage (Vd), an output stage for converting the ion detection voltage into the detection signal (P), the output stage being arranged for drawing a first current dependent on the ion detection voltage, and a supplementary stage for providing a second current (is) dependent on the ion detection voltage to the output stage. The second current may be substantially equal to the first current.

Abstract: A method of analysing a signal generated by a mass analyser comprises receiving a signal generated by the mass analyser, determining the area of a first ion peak of one or more ion peaks in the signal, and estimating the number of ions that contributed to the first ion peak. The number of ions that contributed to the first ion peak is estimated by determining a correction to be applied to the area of the first ion peak from a correction function, and applying the correction to the area of the first ion peak. The correction function describes a relationship between average single ion area and ion mass, mass-to-charge ratio and/or charge for the mass analyser.

Abstract: An ion guide with a switchable ion path for a spectrometer includes a first ion transport aperture configured to receive an ion beam. A radio frequency surface comprises a plurality of radio frequency electrodes arranged on a first surface, such that the radio frequency electrodes are parallel. A radio frequency voltage source is configured to apply an alternating radio frequency phase to each radio frequency electrode. A DC potential source is configured to apply a DC gradient across the radio frequency surface. The DC gradient is configured to guide an ion beam via either a first ion path or a second ion path. Ions travelling in the first ion path are directed between the first ion transport aperture and a second ion transport aperture. Ions travelling in the second ion path are directed between the first ion transport aperture and a third ion transport aperture.

Abstract: An ion optical arrangement (1) for use in a mass spectrometer comprises a collision cell defining an ion optical axis along which ions may pass, electrodes comprising a set of parallel poles (11A, 11B, 11C) arranged in the collision cell, and a voltage source for providing voltages to the electrodes to produce electric fields. The ion optical arrangement is arranged for switching between a first operation mode in which the collision cell is pressurized and a second operation mode in which the collision cell is substantially evacuated. The ion optical arrangement is further arranged for producing a radio frequency electric focusing field in the first operation mode and a static electric focusing field in the second operation mode.

Abstract: A method of analysing labelled analyte ions comprises fragmenting labelled analyte ions to produce analyte fragment ions and reporter ions or complementary ions, analysing the analyte fragment ions using a time-of-flight mass analyser operating in a first mode of operation, and analysing the reporter ions or the complementary ions using the time-of-flight mass analyser operating in a second mode of operation. In the first mode of operation, ions are caused to travel along a flight path having a first length, and in the second mode of operation, ions are caused to travel along a flight path having a second length, wherein the second length is greater than the first length.

Abstract: Ions are injected into an orbital electrostatic trap. An ejection potential is applied to an ion storage device, to cause ions stored in the ion storage device to be ejected towards the orbital electrostatic trap. Synchronous injection potentials are applied to a central electrode of the orbital electrostatic trap and a deflector electrode associated with the orbital electrostatic trap, to cause the ions ejected from the ion storage device to be captured by the electrostatic trap such that they orbit the central electrode. Application of the ejection potential and application of the synchronous injection potentials are each started at respective different times, the difference in times being selected based on desired values of mass-to-charge ratios of ions to be captured by the orbital electrostatic trap.

Abstract: A signal processing unit comprises: at least one data signal input line adapted to receive a measured data signal generated by an image current, the measured data signal comprising an added crosstalk signal induced by a source of electromagnetic disturbance; at least one disturbance signal input line adapted to receive a decoupled disturbance signal, extracted from the source of electromagnetic disturbance; an output line adapted to supply a compensated data signal; a conditioning module, to which the decoupled disturbance signal is supplied via the disturbance signal input line and which provides a compensation signal; and an adding module, to which the measured data signal and the compensation signal are provided and in which the measured data signal and the compensation signal are superposed, whereby the decoupled disturbance signal is conditioned by the conditioning module such that the compensation signal essentially corresponds to an inverted added crosstalk signal.

Abstract: An ion optical arrangement (1) for use in a mass spectrometer comprises electrodes (11, 12, 14) comprising a multipole arrangement defining an ion optical axis, and a voltage source for providing voltages to the electrodes to produce electric fields. The ion optical arrangement is configured for producing a radio frequency electric focusing field for focusing ions on the ion optical axis. The radio frequency electric focusing field has a varying frequency so as to reduce any mass dependence of ion trajectories through the ion optical arrangement. The ion optical arrangement may further he configured for producing a static electric field in response to a DC bias voltage applied to the multipole arrangement. A superimposed varying electric field may be produced by superimposing an AC voltage upon the DC bias voltage.

Abstract: A voltage supply and a method for calibrating the voltage supply are provided. The voltage supply is for providing a reference voltage to supply a voltage to at least one electrode. The voltage supply comprises: an ultra-stable DC voltage source, an accurate DC voltage source, a tuning unit, a comparator, and a control unit. An ultra-stable voltage is applied to the tuning unit, which is provided based on a supplied voltage of the ultra-stable DC voltage source. The tuning unit provides an output voltage. A voltage based on the output voltage of the tuning unit is compared by the comparator with an accurate voltage. The accurate voltage is provided based on a supplied voltage of the accurate DC voltage source.

Abstract: An ion guide may comprise a set of plate electrodes, each plate electrode having a plurality of apertures formed therethrough. The set of plate electrodes are spatially arranged such that a relative positioning of each plurality of apertures of a respective plate electrode of the set of plate electrodes and respective adjacent plate electrodes of the set of plate electrodes defines a continuous ion flight path through the respective plurality of apertures of each plate electrode of the set of plate electrodes. The continuous ion flight path has a helical-based and/or spiral-based shape.

Abstract: An ion optical arrangement (1) for use in a mass spectrometer comprises electrodes (11, 12, 14) comprising a multipole arrangement defining an ion optical axis, and a voltage source for providing voltages to the electrodes to produce electric fields. The ion optical arrangement is configured for producing a radio frequency electric focusing field for focusing ions on the ion optical axis. The radio frequency electric focusing field has a varying frequency so as to reduce any mass dependence of ion trajectories through the ion optical arrangement. The ion optical arrangement may further be configured for producing a static electric field in response to a DC bias voltage applied to the multipole arrangement. A superimposed varying electric field may be produced by superimposing an AC voltage upon the DC bias voltage.

Abstract: Disclosed are techniques for mass spectrometry. In one example, an isotopologue of a target analyte is added to a sample. The sample and isotopologue are analyzed as it elutes from a chromatography system to form precursor ions. The precursor ions are mass analysed using a data independent acquisition (DIA) methodology comprising performing mass analysis scans in the MS1 domain and performing mass analysis scans in the MS2 domain. Upon identifying that the isotopologue is eluting from the chromatography system, a plurality of target scans are performed, each having a target isolation window including a mass to charge ratio representative of the target analyte over the duration of a chromatographic peak of the isotopologue for at least one of identification and quantitation of the target analyte. The target scans are configured to provide additional quantitation data for the target analyte.

Abstract: A pulse shaping circuit for a spectrometer comprises a circuit input terminal for receiving detector pulses from an analog ion detector, a flip-flop for receiving detector pulses from the circuit input terminal, a delay unit for receiving output pulses from the flip-flop and feeding delayed output pulses to a reset input terminal of said flip-flop, and a circuit output terminal for supplying the output pulses or the delayed output pulses to a counter. The duration of the output pulses and the minimum duration of the interval between the output pulses is determined by the delay unit. The pulse shaping circuit may comprise at least one Schmitt trigger.

Abstract: A method of mass spectrometry for analyzing a sample within a mass range of interest includes the steps: ionizing the sample to produce a plurality of precursor ions; performing an MS1 scan of the precursor ions comprising mass analyzing the precursor ions across the mass range of interest, to obtain an MS1 mass spectrum of the precursor ions; determining ion intensity values within the MS1 mass spectrum; selecting precursor mass segments within the mass range of interest, and for each precursor mass segment: fragmenting the precursor ions within that precursor mass segment; and performing an MS2 scan of the fragmented ions by: controlling an amount of fragmented ions for that precursor mass segment, based on an intensity value for that precursor mass segment derived from the MS1 spectrum; and mass analyzing the amount of fragmented ions.