Systems and methods described herein relate to a mass spectroscopy system having multipole ion guides that can receive ions from an ion source for transmission to downstream mass analyzers, while preventing unwanted ions from being transmitted into the high-vacuum chambers of mass spectrometer systems. At least one ion guide can have two or more auxiliary electrodes that extend along at least a portion of the ion guide. A power supply provides an RF voltage to the poles of the ion guide for radially confining the ions within the internal volume of the ion guide. The auxiliary electrodes are also provided with an auxiliary electrical signal that can selectively radially deflect from the internal volume at least a portion of low m/z ions so as to prevent transmission of undesired low m/z ions into the downstream mass analyzers.
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