Mass spectrometer device and method using scanned phase applied potentials in ion guidance

摘要

An ion guide or mass analyzer is disclosed comprising a plurality of electrodes having apertures through which ions are transmitted in use. A pseudo-potential barrier is created at the exit of the ion guide or mass analyzer. The amplitude or depth of the pseudo-potential barrier is inversely proportional to the mass to charge ratio of an ion. One or more transient DC voltages are applied to the electrodes of the ion guide or mass analyzer in order to urge ions along the length of the ion guides or mass analyzer. The amplitude of the transient DC voltage applied to the electrode may be increased with time so that ions are caused to be emitted from the ion guide or mass analyzer in reverse order of their mass to charge ratio.

主权项

1. A mass analyser comprising:
an ion guide having a plurality of electrodes; an RF voltage supply for applying first RF voltages to one or more of the electrodes such that, in use, a first axial pseudo-potential barrier or well is created along at least a portion of the axial length of said ion guide; and a DC voltage supply for applying one or more DC voltages to the electrodes of the ion guide such that, in use, ions are urged through the ion guide and ions having a first range of mass to charge ratios are urged passed the barrier or well, whereas ions having a second, different range of mass to charge ratios are unable to pass the barrier or well.