Abstract: A method of imaging analyte elements in an organic sample includes providing the sample as a layer on a substrate and reacting the sample on the substrate to produce one or more volatile products that leave the sample while the one or more elements remain in the sample. A majority of the sample layer by weight is removed from the substrate by the reaction and the remaining sample layer is enriched in the one or more elements which are not spatially disturbed by the reaction. The method including subsequently detecting the one or more elements in the concentrated sample layer using an imaging elemental analyzer.

Abstract: A first mass spectrometer includes a first introduction device configured to select between a reference material and a first portion of an analyte and introduce the selected one of the reference material or the first portion of the analyte to an ion source, the first mass spectrometer being configured to provide third molecular analyte ions to a detector at a first mass resolution of about 30,000 or greater. A system includes the first mass spectrometer and a second mass spectrometer. A method for determining the isotopic composition of an analyte in a sample includes converting a first portion of the analyte to first molecular analyte ions, filtering out second molecular analyte ions, filtering out third molecular analyte ions, detecting two or more of the third molecular analyte ions at a mass resolution of about 30,000 or greater to determine the isotopic composition of at least a portion of the analyte.

Abstract: A gas inlet system for an isotope ratio spectrometer and a method for coupling analyte gas to an isotope ratio spectrometer are disclosed. A variable volume reservoir is located between a supply of analyte gas and a spectrometer. The reservoir's internal volume is controllably adjusted at a pre-determined rate to generate a defined flow of analyte gas or mixture to or from the reservoir. Analyte gas and carrier gas are taken up by the reservoir on increasing the reservoir's internal volume and then expelled from the reservoir to the spectrometer on decreasing the reservoir's internal volume. An open split can be used together with the reservoir to facilitate splitting away and hence dilution of analyte within the reservoir. A method for cleaning the gas inlet system is provided, which involves flushing the system with carrier gas.

Abstract: The present inventive concepts relate to determining an isotope ratio using mass spectrometry. Mass spectra of ions are obtained by generating ions, guiding the ions through a device having a mass transfer function that varies with ion current, providing at least some of the ions to a mass analyser and obtaining a mass spectrum of the ions and determining the ion current of the ions provided to the mass analyser. An isotope ratio of the ions is determined for each mass spectrum. Using the determined isotope ratio and determined ion current for each mass spectrum, a calibration relationship is determined that characterises the variation of the determined isotope ratios and the measured ion currents across the mass spectra. Then, a measured isotope ratio obtained at a determined ion current is adjusted using the calibration relationship to adjust the measured isotope ratio to an adjusted isotope ratio corresponding to a selected ion current.

Abstract: The present inventive concepts relate to determining an isotope ratio using mass spectrometry. Mass spectra of ions are obtained by generating ions, guiding the ions through a device having a mass transfer function that varies with ion current, providing at least some of the ions to a mass analyzer and obtaining a mass spectrum of the ions and determining the ion current of the ions provided to the mass analyzer. An isotope ratio of the ions is determined for each mass spectrum. Using the determined isotope ratio and determined ion current for each mass spectrum, a calibration relationship is determined that characterizes the variation of the determined isotope ratios and the measured ion currents across the mass spectra. Then, a measured isotope ratio obtained at a determined ion current is adjusted using the calibration relationship to adjust the measured isotope ratio to an adjusted isotope ratio corresponding to a selected ion current.

Abstract: A method of static gas mass spectrometry is provided. The method includes the steps of: introducing a sample gas comprising two or more isotopes to be analyzed into a static vacuum mass spectrometer at a time, t0; operating an electron impact ionization source of the mass spectrometer with a first electron energy below the ionization potential of the sample gas for a first period of time that is following t0 until a time t1; and operating the electron impact ionization source with a second electron energy at least as high as the ionization potential of the sample gas for a second period of time that is after time t1. The first time period from t0 to t1 is a period corresponding to a period taken for the isotopes of the sample gas to equilibrate in the mass spectrometer. A constant ion source temperature is preferably maintained. Also provided is a static gas mass spectrometer.

Abstract: A first mass spectrometer includes a first introduction device configured to select between a reference material and a first portion of an analyte and introduce the selected one of the reference material or the first portion of the analyte to an ion source, the first mass spectrometer being configured to provide third molecular analyte ions to a detector at a first mass resolution of about 30,000 or greater. A system includes the first mass spectrometer and a second mass spectrometer. A method for determining the isotopic composition of an analyte in a sample includes converting a first portion of the analyte to first molecular analyte ions, filtering out second molecular analyte ions, filtering out third molecular analyte ions, detecting two or more of the third molecular analyte ions at a mass resolution of about 30,000 or greater to determine the isotopic composition of at least a portion of the analyte.

Abstract: A method of imaging analyte elements in an organic sample includes providing the sample as a layer on a substrate and reacting the sample on the substrate to produce one or more volatile products that leave the sample while the one or more elements remain in the sample. A majority of the sample layer by weight is removed from the substrate by the reaction and the remaining sample layer is enriched in the one or more elements which are not spatially disturbed by the reaction. The method including subsequently detecting the one or more elements in the concentrated sample layer using an imaging elemental analyzer.

Abstract: A gas inlet system 20 for an isotope ratio spectrometer 1 and a method for coupling analyte gas to an isotope ratio spectrometer 1 are disclosed. A variable volume reservoir 5 is located between a supply of analyte gas 9,11 and a spectrometer 1. The reservoir's internal volume is controllably adjusted at a pre-determined rate to generate a defined flow of analyte gas or mixture to or from the reservoir 5. Analyte gas and carrier gas are taken up by the reservoir 5 on increasing the reservoir's internal volume and then expelled from the reservoir to the spectrometer 1 on decreasing the reservoir's internal volume. An open split 3,8 can be used together with the reservoir 5 to facilitate splitting away and hence dilution of analyte within the reservoir 5. A method for cleaning the gas inlet system 20 is provided, which involves flushing the system with carrier gas.

Abstract: The present invention can be directed to a mass spectrometer, relevant parts thereof like replacement kits or upgrading kits and/or mass spectrometry methods. A mass spectrometer according to the present invention can comprise at least one ion source for generating a beam of ions from a sample. Moreover at least one mass filter downstream of the ion source can be provided and adapted to select ions from the beam by their mass-to-charge ratio (m/z). Furthermore at least one collision cell arranged downstream of the mass filter can be arranged. At least one sector field mass analyser arranged downstream of the collision cell can be further provided and at least one ion multicollector comprising a plurality of ion detectors arranged downstream of the mass analyser, for detecting a plurality of different ion species in parallel and/or simultaneously.

Abstract: A system for concentrating an analyte gas in a gas stream of an analytical system is provided. The system comprises at least one separation device, at least one gas inlet line, at least one detector, at least one gas outlet line, a first split line in connected to the gas inlet line, and a first split valve for controlling gas flow in the first split line. Also provided is a method for concentrating an analyte gas.

Abstract: A mass spectrometry method comprising steps of generating an ion beam from an ion source; directing the ion beam into a collision cell; introducing into the collision cell through a gas inlet on the collision cell a charge-neutral analyte gas or reaction gas; ionizing the analyte gas or reaction gas in the collision cell by means of collisions between the analyte gas or reaction gas and the ion beam; transmitting ions from the ionized analyte gas or reaction gas from the collision cell into a mass analyzer; and mass analyzing the transmitted ions of the ionized analyte or reaction gas. The methods can be applied in isotope ratio mass spectrometry to determine the isotope abundance or isotope ratio of a reaction gas used in mass shift reactions between the gas and sample ions, to determine a corrected isotope abundance or ratio of the sample ions.

Abstract: The invention provides a mass spectrometer that comprises a collision cell having an axial electric field that enhances transmission of light ions, especially elemental ions, through the collision cell, relative to heavier ions. The invention also provides methods of mass spectrometry that employ an axial electric field that is provided in a collision cell.

Abstract: Methods of determining isobaric interference during mass analysis in a mass spectrometer are provided. The methods comprise comparing interference-free reaction profiles of a chemical species to reaction profiles of the same chemical species that may comprise isobaric interference, wherein a determination of a difference between the profiles is an indication of isobaric interference being present. Methods of quantifying isobaric interference are also provided, including methods of correcting isotope ratios determined in the presence of isobaric interference.

Abstract: A method of imaging analyte elements in an organic sample includes providing the sample as a layer on a substrate and reacting the sample on the substrate to produce one or more volatile products that leave the sample while the one or more elements remain in the sample. A majority of the sample layer by weight is removed from the substrate by the reaction and the remaining sample layer is enriched in the one or more elements which are not spatially disturbed by the reaction. The method including subsequently detecting the one or more elements in the concentrated sample layer using an imaging elemental analyzer.

Abstract: A sample preparation apparatus for an elemental analysis system comprising a sample combustion and/or reduction and/or pyrolysis arrangement for receiving a sample of material to be analysed, and producing therefrom a sample gas flow containing atoms, molecules and/or compounds; a gas chromatography (GC) column into which the sample gas flow is directed; a heater for heating at least a part of the GC column; and a controller for controlling the heater. The controller is configured to control the heater so as to increase the temperature of at least the part of the GC column whilst the sample gas flow in the GC column elutes.

Abstract: A method of imaging analyte elements in an organic sample includes providing the sample as a layer on a substrate and reacting the sample on the substrate to produce one or more volatile products that leave the sample while the one or more elements remain in the sample. A majority of the sample layer by weight is removed from the substrate by the reaction and the remaining sample layer is enriched in the one or more elements which are not spatially disturbed by the reaction. The method including subsequently detecting the one or more elements in the concentrated sample layer using an imaging elemental analyzer.

Abstract: An isotope ratio of a continuous sample is measured in an isotope ratio spectrometer. At least one sample isotope ratio is measured over a measurement time period tns, (n?1) and a sample concentration cns is measured over at least a part of the measurement time period tns. A reference gas concentration cnref for the spectrometer is selected for reference to the sample measured during the measurement time period tns, on the basis of the measured sample concentration cnref. An isotope ratio of the reference gas is measured at the selected reference gas concentration cnref in the spectrometer. The at least one isotope ratio of the sample measured during the measurement time period tns is calibrated using the measured isotope ratio of the reference gas at the corresponding reference gas concentration cnref and a plurality of calibrated isotope ratios and a plurality of sample gas concentration measurements are determined, each being for a different time.

Abstract: A gas inlet system for introducing gas into an isotope ratio analyzer, the gas inlet system including a reference system comprising: a first supply of a reference gas having a first known isotope ratio; a supply of a carrier gas, wherein the supplies of reference gas and carrier gas are each connected by respective reference and carrier gas lines to a first mixing junction where the reference gas and carrier gas combine; a mixing zone connected downstream of the first mixing junction wherein the combined reference gas and carrier gas mix together; an exit line for transporting the mixed gas from the mixing zone to the isotope ratio analyzer; and an opening on the exit line, wherein the opening is downstream of the mixing zone. Also provided is a method of determining an isotope ratio.

Abstract: A method of static gas mass spectrometry is provided. The method includes the steps of: introducing a sample gas comprising two or more isotopes to be analyzed into a static vacuum mass spectrometer at a time, t0; operating an electron impact ionization source of the mass spectrometer with a first electron energy below the ionization potential of the sample gas for a first period of time that is following t0 until a time t1; and operating the electron impact ionization source with a second electron energy at least as high as the ionization potential of the sample gas for a second period of time that is after time t1. The first time period from t0 to t1 is a period corresponding to a period taken for the isotopes of the sample gas to equilibrate in the mass spectrometer. A constant ion source temperature is preferably maintained. Also provided is a static gas mass spectrometer.