An ion transport device for a mass spectrometer, comprising: a plurality of pole rod pairs (200, 300, 400) arranged in parallel, the pole rod pairs defining a plurality of ion transport cells, each ion transport cell uniquely corresponding to a contiguous group of a fixed number of pole rod pairs (200, 300, 400), such that no two ion transport cells share a common pole rod pair (200, 300, 400); a controller which is configured to: apply voltages in a repeating voltage pattern (500, 600, 700, 800) to the pole rod pairs (200, 300, 400) thereby creating a plurality of potential wells capable of capturing ions, wherein each ion transport cell receives the same pattern of voltages (500, 600, 700, 800); move the potential wells defined by the repeating voltage pattern (500, 600, 700, 800) along the pole rod pairs (200, 300, 400) to move captured ions within and between the plurality of ion transport cells along the ion transport device wherein the ions are transported along the ion transport device in a direction perpendicular to the primary axes of the pole rods (200, 300, 400); and apply at least one ejection voltage to one or more electrodes (114, 116; 304A, B-316A, B; 404A, B-416A, B) to cause ions to be ejected from the ion transport device in a direction parallel to the pole rods (200, 300, 400); and wherein the ion transport device is configured to receive ions from a fragmentation cell travelling in a direction parallel to the primary axes of the pole rods and initially capture the ions in a first potential well of a first ion transport cell of the repeating voltage pattern, wherein the pole rods are divided into a plurality of segments and the controller is configured to apply a DC potential gradient across the segmented rods to eject the ions from the ion transport device. a plurality of pole rod pairs (200, 300, 400) arranged in parallel, the pole rod pairs defining a plurality of ion transport cells, each ion transport cell uniquely corresponding to a contiguous group of a fixed number of pole rod pairs (200, 300, 400), such that no two ion transport cells share a common pole rod pair (200, 300, 400); a controller which is configured to: apply voltages in a repeating voltage pattern (500, 600, 700, 800) to the pole rod pairs (200, 300, 400) thereby creating a plurality of potential wells capable of capturing ions, wherein each ion transport cell receives the same pattern of voltages (500, 600, 700, 800); move the potential wells defined by the repeating voltage pattern (500, 600, 700, 800) along the pole rod pairs (200, 300, 400) to move captured ions within and between the plurality of ion transport cells along the ion transport device wherein the ions are transported along the ion transport device in a direction perpendicular to the primary axes of the pole rods (200, 300, 400); and apply at least one ejection voltage to one or more electrodes (114, 116; 304A, B-316A, B; 404A, B-416A, B) to cause ions to be ejected from the ion transport device in a direction parallel to the pole rods (200, 300, 400); and wherein the ion transport device is configured to receive ions from a fragmentation cell travelling in a direction parallel to the primary axes of the pole rods and initially capture the ions in a first potential well of a first ion transport cell of the repeating voltage pattern, wherein the pole rods are divided into a plurality of segments and the controller is configured to apply a DC potential gradient across the segmented rods to eject the ions from the ion transport device. apply voltages in a repeating voltage pattern (500, 600, 700, 800) to the pole rod pairs (200, 300, 400) thereby creating a plurality of potential wells capable of capturing ions, wherein each ion transport cell receives the same pattern of voltages (500, 600, 700, 800); move the potential wells defined by the repeating voltage pattern (500, 600, 700, 800) along the pole rod pairs (200, 300, 400) to move captured ions within and between the plurality of ion transport cells along the ion transport device wherein the ions are transported along the ion transport device in a direction perpendicular to the primary axes of the pole rods (200, 300, 400); and apply at least one ejection voltage to one or more electrodes (114, 116; 304A, B-316A, B; 404A, B-416A, B) to cause ions to be ejected from the ion transport device in a direction parallel to the pole rods (200, 300, 400); and wherein the ion transport device is configured to receive ions from a fragmentation cell travelling in a direction parallel to the primary axes of the pole rods and initially capture the ions in a first potential well of a first ion transport cell of the repeating voltage pattern, wherein the pole rods are divided into a plurality of segments and the controller is configured to apply a DC potential gradient across the segmented rods to eject the ions from the ion transport device.