Abstract: A method of separating ions is disclosed. The method includes a step of providing a FAIMS analyzer region for separating ions, the FAIMS analyzer region including at least one region of segmentation. The segmentation permits ion trapping, and a combination trapping and gating that permits high efficiency of ions collection from continuous ion sources. The ions are separated in segmented FAIMS, according to their high-field mobility properties, and by using the method described herein according to their low-field mobility. The ions are separated by low field mobility using stationary potential gradients formed by voltages applied to the segments, and by traveling potential gradients of various shapes. The ions are separated along the longitudinal direction in cylindrical FAIMS, and may be detected in a time-of-arrival fashion as the ions leave the ion outlet of FAIMS or optionally the ions other than selected are caused to collide with the electrodes and only the selected ions transmitted.

Abstract: An apparatus for controllably varying specificity of a FAIMS-based ion separation includes a first electrode surface portion defining an ion inlet within a portion thereof and a second electrode surface portion defining an ion outlet within a portion thereof. The second electrode surface portion is spaced-apart from the first electrode surface portion along a first direction and disposed in a facing relationship relative to the first electrode surface portion so as to define a FAIMS analyzer region therebetween. An intermediate electrode is disposed between the first electrode surface portion and the second electrode surface portion, the intermediate electrode for defining a transition point of an average ion flow path between the ion inlet and the ion outlet.