Abstract: Method for obtaining gaseous ammonium (NH4+) from an ion source, the ion source comprising a first area (1) and a second area (2) in a fluidly conductive connection, comprising the steps of a) introducing N2 and H2O into the first area (1) and second area (2) of the ion source; b) applying an ionization method to the mixture of N2 and H2O in the first area (1); c) applying at least one electric field or adjusting pressure conditions or a combination of applying at least one electric field and adjusting pressure conditions promoting flow of ions from the first area (1) to the second area (2) and inducing reactions of the ions in the second area (2); d) conducting NH4+ out of the ion source. Ion Molecule Reaction-Mass Spectrometry instrument implementing this method for producing NH4+ and then conducting NH4+ to the reaction region.

Abstract: The present invention relates to an apparatus and a method for IMR-MS and/or PTR-MS, comprising a sample gas inlet (202, 206), a first ion source (209), a reaction chamber (203), a mass analyzer (204), wherein the reaction chamber (203) and the mass analyzer (204) are arranged along a central axis (A), characterized by a second ion source (209), wherein the sample gas inlet (202, 206) is arranged to introduce gas essentially along the central axis (A) and is connected to the reaction chamber (203); wherein the first ion source (209) and the second ion source (209) are arranged so as to emit reagent ions essentially perpendicularly to the central axis (A); said apparatus further comprising at least one electrode (302, 303, 304, 305), such that the reagent ions emitted from the first or second ion source (209) can be deflected into the reaction chamber (203) essentially in the downstream direction of the central axis (A).

Abstract: Ion-molecule-reaction—mass spectrometry (IMR-MS) device, comprising an ion source, an adjacent reaction chamber and a mass spectrometer subsequent to the reaction chamber, wherein the reaction chamber comprises an RF device for creating a temporally changing electromagnetic field and wherein an adjustable reduced electric field strength (E/N) can be applied to the reaction chamber, characterized by an input device for entering a desired reduced electric field strength (E/N) by an operator when operating said IMR-MS device for analyzing a sample, and a controlling device that operates the IMR-MS device by adjusting the settings of the IMR-MS device relating to a defined data set of a pseudo reduced electric field strength (PE/N1,2) for the entered reduced electric field strength (E/N), wherein the pseudo reduced electric field strength (PE/N1,2) has been determined by analyzing a first analyte (A1) in the IMR-MS device, wherein intensity signals (RS1) of at least two product ions of the analyte (A1) are record

Abstract: The invention provides a method and system for analyzing a gas for the presence of a reactant compound via reaction of primary ions of a specific type. A source gas is introduced to a reaction chamber and ionized in this chamber. The pressure in the reaction chamber is adjusted to avoid the formation of protonated species and other impurities. The primary ions generated in the reaction chamber are transferred to a drift tube. The gas to be analyzed is diluted with a carrier gas and the resulting mixture is introduced into the drift tube. The ionization energy of the carrier gas is equal to or higher than the ionization energy of the primary ions. The product ions resulting in the drift tube from a reaction of the primary ions with the reactant present in the gas to be analyzed are then detected, for example using a mass spectrometer. Preferably, an existing PTR-MS setup is used to perform the method of the present invention.