A process for the ionization of gaseous samples by means of dielectric barrier discharge and, for the subsequent analysis of the sample ions generated in an analytical instrument

摘要

The present invention relates to a process for the ionization of gaseous samples by means of dielectric barrier discharge and, for the subsequent analysis of the sample ions generated in an analysis device, in particular a mass spectrometer or a the ion mobility spectrometer, wherein the sample ions are generated by a plasma which, by means of a dielectrically impeded discharge is brought about, wherein the dielectrically impeded discharge is produced in such a way that a noble gas through a capillary tube made of a dielectric material is supplied, wherein by means of two adjacent to the outlet region of the capillary is arranged on the outside of the capillary, electrically insulated electrodes an alternating voltage is applied and the gaseous sample is supplied to the outlet area of the capillary, an asymmetrical square-wave voltage as the ac voltage is applied, in which the clock duration of the active voltage signal is substantially shorter than the clock duration of the inactive voltage signal is set.