RF-ONLY DETECTION SCHEME AND SIMULTANEOUS DETECTION OF MULTIPLE IONS

摘要

A mass spectrometer apparatus and method for conducting simultaneous MS/MS analysis including: a device to select a precursor ion having a specified m/z; a gas-filled collision cell; an RF-only multipole mass spectrometer, the mass spectrometer having a generator attached thereto for generating at least two auxiliary AC fields in the RF-only multipole mass spectrometer; a gate for providing a repulsive DC or AC barrier downstream to an exit of the RF-only multipole mass spectrometer; an ion detection system situated downstream from the DC or AC barrier for measuring an ion current derived from ions that overcome the repulsive barrier. The mass spectrometer may also be configured so that each of the auxiliary AC fields are generated by the introduction of individual auxiliary AC frequencies and each frequency is amplitude modulated at a unique frequency.