Patent ID: 6639212
Filing Date: 2003-10-28
Classification: B01D,G01N,H01J

Abstract:
A method for identifying ions having substantially the same mass to charge ratio but having different ion mobility characteristics, comprising the steps of:a) providing at least one ionization source of ions; b) providing an analyzer region defined by a space between at least first and second spaced apart electrodes, said analyzer region being in communication with a gas inlet, a gas outlet, an ion inlet and an ion outlet, and introducing said ions into said analyzer region through said ion inlet; c) applying an asymmetric waveform voltage and a direct current compensation voltage to at least one of said electrodes; d) setting said asymmetric waveform voltage; e) varying said direct current compensation voltage and measuring resulting transmitted ions at said ion outlet, so as to produce a compensation voltage scan for said transmitted ions; and f) identifying peaks in said compensation voltage scan.