Abstract: Disclosed is a system for screening of traces of illicit substances that may be harmful, such as explosives, radioactive substances, toxics or drugs for example, from very tiny trace concentrations to be detected by way of mass spectrometry being applied to the detached and pre-concentrated particulate matter by the system. Also disclosed is a method in accordance of the system, an arrangement or device as a system element of the system, and a software code on computer readable medium, to control the system and/or acquire data from the system.

Abstract: A device for ionizing sample particles of a sample gas flow comprises a first flow tube for providing the sample gas flow, and an introducing means for providing H2SO4 molecules to an interaction region. In addition the device comprises a generator for producing reagent primary ions from particles of candidate reagent gas flow essentially in a primary ion production region. The device is configured to introduce said reagent primary ions with H2SO4 molecules in said interaction region in order to arrange interaction between the reagent primary ions and the H2SO4 molecules, thereby producing HSO4? ions and again to produce HSO4? ion clusters comprising HSO4? ions and at least two H2SO4 molecules via interactions of HSO4? with other H2SO4 molecules in said interaction region.

Abstract: A device for ionizing sample particles of a sample gas flow comprises a first flow tube for providing the sample gas flow, and an introducing means for providing H2SO4 molecules to an interaction region. In addition the device comprises a generator for producing reagent primary ions from particles of candidate reagent gas flow essentially in a primary ion production region. The device is configured to introduce said reagent primary ions with H2SO4 molecules in said interaction region in order to arrange interaction between the reagent primary ions and the H2SO4 molecules, thereby producing HSO4? ions and again to produce HSO4? ion clusters comprising HSO4? ions and at least two H2SO4 molecules via interactions of HSO4? with other H2SO4 molecules in said interaction region.

Abstract: Properties, such as concentrations, of gas phase bases or acids of a gas sample are determined by providing a sample gas flow, which includes the bases or acids to be determined as sample constituents, as well as also interfering constituents, which are other constituents than the sample constituents. Reagent ions are provided and introduced into the sample gas flow to arrange proton transfer reaction and thereby forming sample ions. Also a dopant is introduced into the sample gas flow to arrange proton transfer reaction between the dopant and the interfering ions thereby forming dopant ions and electrically neutral interfering constituents. For determination the gas flow with the sample ions to be determined is introduced together with the dopant ions to a mass spectrometer in order to determine the properties of the gas phase bases or acids.