MASS SPECTROMETER COMPRISING A GLOW DISCHARGE ION SOURCE FOR ELECTRON TRANSFER DISSOCIATION AND CORRESPONDING METHOD

摘要

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 vapour may be provided through the tubular electrode 14 which is then subsequently ionised 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.