Patent ID: 8653449

Claim:
An ion mobility spectrometer for detection of analyte which comprises a sample inlet for continuously receiving a flow of sample gas which is to be assessed for detection of analyte, without trapping or preconcentration of analyte, wherein the volumetric flow of sample gas is greater than 85 cm 3 /s; an ionization region for formation of primary ions which comprises an ion source, wherein the ionization volume of the ionization source is greater than 5 cm 3 ; a reaction region for receiving the flow of sample gas containing primary ions, wherein primary ions can charge transfer to generate secondary and tertiary ions including analyte ions; an ion shutter; a drift region having an electric field gradient; and an ion detector, wherein the ion shutter gates the entrance of ions into the drift region, the ions in the drift region drift in the electric field gradient to be detected at the ion detector, thereby allowing detection of analyte.