Synchronized ion modification

An ion mobility spectrometer comprising:

• a gate configured to control entry of ions to a drift chamber, the gate disposed on an end of the drift chamber generally opposite a detector;
• an ion modifier disposed between the gate and the detector so the ions, respectively, separate between the gate and the ion modifier based on the ions' ion mobility;
• and
• a controller, coupled to the ion modifier, the controller configured to synchronize operation of the ion modifier so fragments that result from operation of the ion modifier are associated with a portion of the ions based on ion mobility, and wherein the controller is further configured to time operation of the ion modifier to prevent ions that are not in the portion from passing to the detector,
• wherein the ion modifier comprises at least two electrodes that are spaced apart from one another along the drift chamber's length and the at least two electrodes comprise at least one of set of parallel wires, wire meshes, or a combination of parallel wires and wire mesh.

A method comprising:

• separating ions in a drift chamber based on ion mobility;
• fragmenting a portion of the ions, said ions in the portion having substantially similar ion mobilities;
• and
• separating fragments that are ionized, respectively, based on said fragment's ion mobility;
• and
• synchronizing operation of a gate and the ion modifier, wherein the ion modifier comprises at least two electrodes that are spaced apart from one another along the drift chamber's length and the at least two electrodes comprise at least one of set of parallel wires, wire meshes, or a combination of parallel wires and wire mesh to prevent at least some other ions that are not in the portion from passing toward the detector.

One or more computer-readable media comprising instructions, that responsive to being executed by a computing system, cause the computing system to:

• cause an ion modifier comprising at least two electrodes that are spaced apart from one another along the drift chamber's length and the at least two electrodes comprise at least one of set of parallel wires, wire meshes, or a combination of parallel wires and wire mesh, disposed in a drift chamber between a gate and a detector, to modify ions that correspond to other ions that were ambiguously identified during previous operation of the detector;
• identify molecules included in a sample of interest based on ion mobilities associated with fragments that result from the ion modifier modifying the ions formed from the molecules;
• and
• synchronize operation of the gate and the ion modifier to select a portion of the ions to be modified.