Method and apparatus for trapping and storing ions - Patents.com

Abstract

A method and apparatus for ion storage are disclosed. The apparatus for ion storage includes multiple regions. A first region receives ions and transmits the ions to a second region using a first driving potential. The second region is switchable between a first state that generates a first electric field that prevents the ions from further moving into a third region and a second state that generates a second electric field that guides the ions toward the third region. In the first state, the ions are prevented from further movement by the first electric field and accumulate in the second region. In the second state, the ions are moved from the second region to the third region by the second electric field. A method for ion storage involves switching an electric field applied to the region between a trapping state and a releasing state.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 028,768, filed May 22, 2020, which is incorporated by reference in its entirety.

[0002] The present disclosure relates generally to the field of ion mobility spectrometry (IMS) and mass spectrometry (MS). More particularly, the present disclosure relates to methods and apparatus for trapping and storing ions to increase the resolution of ions in IMS and MS systems. [Background technology]

[0003] IMS is a technique for separating and identifying ions in the gas phase based on their mobility. For example, IMS can be used to separate structural isomers and macromolecules with different mobilities. IMS relies on applying a constant or time-varying electric field to a mixture of ions in a static or dynamic background gas. Ions with higher mobility (or smaller collision cross section [CCS]) move faster under the influence of the electric field compared to ions with lower mobility (or larger CCS). By applying an electric field across a separation distance (e.g., in a drift tube) of the IMS device, ions from an ion mixture can be separated in time or space based on their mobility. Ions with different mobilities arrive at the end of the drift tube at different times (temporal separation), and therefore these ions can be identified based on their detection time by a detector located at the end of the drift tube. The resolution of the mobility separation can be altered by changing the separation distance.

[0004] MS is an analytical technique that can separate a mixture of chemical species based on their mass-to-charge ratio. MS involves ionizing the mixture of chemical species followed by accelerating the ion mixture in the presence of an electric and / or magnetic field. In some mass spectrometers, ions with the same mass-to-charge ratio receive the same deflection or time-dependent response. Ions with different mass-to-charge ratios may receive different deflection or time-dependent responses and can be distinguished based on the spatial or temporal location of detection by a detector (e.g., an electron multiplier).

[0005] Combining IMS and MS can produce IMS-MS spectra that can be used in a wide range of applications, including metabolomics, glycobiology, and proteomics. IMS-MS ion separation can be performed by coupling an ion mobility spectrometer to a mass spectrometer. For example, an ion mobility spectrometer can first separate ions based on their mobility. Ions with different mobilities can arrive at the mass spectrometer at different times and are then separated based on their mass-to-charge ratio. One example of an IM spectrometer is the structure for a lossless ion manipulation (SLIM) device, which can produce IMS spectra with minimal ion loss. SLIM devices can use traveling wave separation as one technique to separate ions of different mobility. However, traveling wave separation can result in broad peaks, as in the case of ion mobility separation, especially when traveling wave separation is performed over a long distance.

[0006] Furthermore, the signal-to-noise ratio and resolution upon detection are affected by the number of ions introduced into the IMS device. Accordingly, ion traps have been used to accumulate ions before injecting them for ion mobility separation, but such ion traps are limited by space charge effects. In this regard, ion traps can accumulate a limited number of charges before reaching a space charge capacity at which ions may be lost from trapping. In the past, these limitations have typically been addressed by increasing the path length, which can result in larger and / or more complex devices. In addition, systems and methods have also been developed that provide intermittent or "choppy" traveling waves to sort, compress, or regroup ions into a reduced number of ion mobility bins, resulting in spatial compression of ions and increased resolution of ion packets in IMS. For example, U.S. Patent No. 6,233,933 entitled "Method and Apparatus for Spatial Compression and Increased Mobility Resolution of Ions" discloses modifying the duty cycle of an intermittent traveling wave to compress ion packets into narrower distribution peaks. However, the above methodologies are still limited by the space charge effects and parameters (e.g., velocity, amplitude, waveform, etc.) of the traveling waves utilized. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] U.S. Patent No. 10,018,592 Summary of the Invention [Problem to be solved by the invention]

[0008] Accordingly, there is a need for additional systems and methods for internal trapping and storage of ions to increase resolution and sensitivity within IMS and MS systems. [Means for solving the problem]

[0009] The present disclosure relates to methods and apparatus for internal trapping and storage of ions to increase the resolution of ions in IMS and MS systems.

[0010] According to an embodiment of the present disclosure, an exemplary device for ion accumulation is provided. The device for ion accumulation includes a first region and a second region. The first region is configured to receive ions and generate a first driving potential configured to guide the ions in a first direction across the first region. The second region is configured to receive ions from the first region and switch between a first state, which may be a trapping state, and a second state, which may be a releasing state, and generate a first electric field when in the first state and a second electric field when in the second state. The first electric field is configured to prevent the ions from moving in the first direction into the third region, and the second electric field is configured to guide the ions in the first direction toward the third region. Accordingly, the first electric field can be generated during the trapping state and the second electric field can be generated during the releasing state. When the second region is in the first state, the first driving potential and the first electric field prevent the ions in the second region from exiting the second region and cause the ions to accumulate in the second region. When the second region is in the second state, the second electric field moves ions in the first direction toward the third region.

[0011] In one embodiment, the first driving potential can be a traveling wave. In another embodiment, the first electric field can be a DC voltage. In such an embodiment, the magnitude of the DC voltage can be greater than the voltage bias of the first driving potential. Additionally, in such an embodiment, the second electric field can be a traveling wave, which can be configured to separate ions based on mobility. In other embodiments, the magnitude of the DC voltage can be less than the voltage bias of the first driving potential, and the DC voltage can create a potential well. In such an embodiment, the second electric field can be a DC potential gradient or a traveling wave, which can be configured to separate ions based on mobility.

[0012] In some embodiments, the first electric field can be a traveling wave traveling in a second direction opposite to the first direction, and the second electric field can be a second traveling wave traveling in the first direction. In such embodiments, the second traveling wave can be configured to separate ions based on mobility. Additionally, in such embodiments, the first electric field can be generated during the capture state and the second electric field can be generated during the release state.

[0013] In other aspects, the third region can be configured to receive ions from the second region and generate a second driving potential configured to separate ions based on mobility.

[0014] In yet other aspects, the first region can include a plurality of electrodes disposed on the first surface and arranged along a first direction and configured to generate a first drive potential, and the second region can include one or more electrodes disposed on the first surface and arranged along the first direction, and at least one of the one or more electrodes in the second region can be configured to generate a first electric field when in the first state and generate a second electric field when in the second state.

[0015] In such an embodiment, the device can include a controller configured to apply a first voltage signal to the plurality of electrodes in the first region, apply a second voltage signal to at least one of the one or more electrodes in the second region, and apply a third voltage signal to at least one of the one or more electrodes in the second region. Additionally, the plurality of electrodes can be configured to generate a first driving potential based on the first voltage signal, at least one electrode can be configured to generate a first electric field based on the second voltage signal, and at least one electrode can be configured to generate a second electric field based on the third voltage signal. When the device is in a first mode of operation, the controller applies the second voltage signal to the second plurality of electrodes to place the second region in a first state, and when the device is in a second mode of operation, the controller applies the third voltage signal to the second plurality of electrodes to place the second region in a second state.

[0016] In some embodiments, a first portion of the second region can generate a first electric field when the second region is in a first state, the first portion of the second region can generate a second electric field when the second region is in a second state, and the second portion of the second region can generate a fourth electric field different from the first electric field.

[0017] In some other aspects, the second region can include a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays can include at least three individual electrodes. In such aspects, the first electric field can be generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

[0018] A method for ion accumulation involves introducing ions into a device for ion accumulation having a first region, a second region, and a third region. The method includes generating a driving potential in the first region to guide the ions in a first direction across the first region, and transmitting the ions from the first region to the second region by the driving potential. The method also includes generating a first electric field in the second region to prevent the ions from moving in the first direction into the third region, and accumulating the ions in the second region. The first electric field can be applied during a trapping state. The method further includes switching the first electric field generated in the second region to a second electric field to guide the accumulated ions in the first direction toward the third region. The second electric field can be generated during a release state.

[0019] In some embodiments, the driving potential can be a traveling wave. In other embodiments, the first electric field can be a DC voltage. In such embodiments, the magnitude of the DC voltage can be greater than the voltage bias of the driving potential. In other such embodiments, the second electric field can be a traveling wave, and the method can involve separating ions based on mobility with the traveling wave.

[0020] In other embodiments, the magnitude of the DC voltage can be less than the voltage bias of the first driving potential, and the DC voltage can create a potential well. In such embodiments, the second electric field can be a DC potential gradient or a traveling wave. When the second electric field is a traveling wave, the method can further involve separating ions based on mobility by the traveling wave.

[0021] In yet other embodiments, the first electric field can be a first traveling wave traveling in a second direction opposite the first direction, and the second electric field can be a second traveling wave traveling in the first direction. In such embodiments, the method can further involve separating ions based on mobility with the traveling wave. Additionally, in such embodiments, the first electric field can be generated during the trapping state and the second electric field can be generated during the release state.

[0022] In one aspect, the method can also involve transferring ions accumulated in the second region to a third region, generating a second drive potential in the third region, and separating the ions based on mobility with the second drive potential.

[0023] In some embodiments, a first portion of the second region can generate a first electric field and a second electric field, and a second portion of the second region can generate a fourth electric field that is different from the first electric field.

[0024] In some other aspects, the second region can include a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays can include at least three individual electrodes. In such aspects, the first electric field can be generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

[0025] In another aspect, an apparatus for ion accumulation includes an ion channel, a first region, a second region, a third region, and a controller. The ion channel is defined between a first surface and a second surface, extends along a first longitudinal direction and a first transverse direction, and is configured to receive a flow of ions. The first region includes a plurality of electrodes disposed on the first surface and disposed along the first longitudinal direction. The second region includes one or more electrodes disposed on the first surface and disposed along the first longitudinal direction. The controller is configured to apply a first voltage signal to the plurality of electrodes of the first region, apply a second voltage signal to one or more electrodes of the second region, and apply a third voltage signal to one or more electrodes of the second region. The second voltage signal can be applied during a capture mode of operation, and the third voltage signal can be applied during a release mode of operation. The plurality of electrodes of the first region are configured to generate a first drive potential traveling along the first longitudinal direction based on the first voltage signal. The first drive potential is configured to guide ions in a first longitudinal direction across the ion channel. One or more electrodes of the second region are configured to generate a first electric field, based on a second voltage signal, that prevents ions from traveling along the first longitudinal direction into the third region. The first electric field can be generated during a trapping mode of operation. The one or more electrodes of the second region are configured to generate a second electric field, based on a third voltage signal, that is configured to guide ions along the first longitudinal direction toward the third region. The third voltage signal can be generated during a releasing mode of operation. When the device is in a first mode of operation, which can be a trapping mode of operation, the controller applies a second voltage signal to the one or more electrodes of the second region, and the first drive potential and the first electric field prevent ions in the second region from exiting the second region, thereby accumulating ions in the second region. When the device is in a second mode of operation, which may be a release mode of operation, the controller applies a third voltage signal to one or more electrodes in the second region, and the second electric field moves ions in the first direction toward the third region.

[0026] In some embodiments, the first voltage signal can be a traveling wave. In other embodiments, the second voltage signal can be a DC voltage. In such embodiments, the magnitude of the DC voltage can be greater than the voltage bias of the first driving potential. Also, in such embodiments, the third voltage signal can be a traveling wave, and the traveling wave can be configured to separate ions based on mobility.

[0027] In other embodiments, a second voltage signal can be applied to a single electrode in the second region.

[0028] In yet other embodiments, the magnitude of the DC voltage can be less than the voltage bias of the first driving potential, and the DC voltage can create a potential well. In such embodiments, the third voltage signal can be a DC potential gradient or traveling wave that can be configured to separate ions based on mobility. In such embodiments, a DC voltage can be applied to two or more electrodes in the second region.

[0029] In one embodiment, the second voltage signal can be a traveling wave traveling in a second direction opposite to the first direction, and the third voltage signal can be a second traveling wave traveling in the first direction. In such an embodiment, the second traveling wave can be configured to separate ions based on mobility. Additionally, in such an embodiment, the second voltage signal can be applied during a capture mode of operation and the third voltage signal can be applied during a release mode of operation.

[0030] In another aspect, the third region can include a plurality of electrodes disposed on the first surface and arranged along the first longitudinal direction. The third region can be configured to receive ions from the second region and generate a second drive potential configured to separate ions based on mobility.

[0031] A method for ion storage involves introducing a flow of ions into an ion channel of an ion storage device. The storage device includes a first surface, a second surface, a first region including a plurality of electrodes disposed on the first surface and arranged along a first longitudinal direction, a second region including one or more electrodes disposed on the first surface and arranged along the first longitudinal direction, and a third region. A first ion channel is defined between the first surface and the second surface and extends along a first longitudinal direction and a first lateral direction. The method also includes applying, by a controller, a first voltage signal to the plurality of electrodes of the first region and generating, by the plurality of electrodes of the first region, a first driving potential that travels along the first longitudinal direction. The first driving potential is also configured to guide the ions in the ion channel in the first longitudinal direction. The method also includes transmitting the ions in the ion channel from the first region to the second region along the first longitudinal direction by the first driving potential. The method further includes applying, by the controller, a second voltage signal to one or more electrodes in the second region and generating, by the one or more electrodes in the second region, a first electric field based on the second voltage signal. During a capture mode of operation, the second voltage signal can be applied and the first electric field can be generated. The method also includes preventing ions from moving in a first direction into the third region by the first electric field and accumulating ions in the second region. The method further includes switching the second voltage signal applied by the controller to the second region to a third voltage signal to guide ions accumulated in the second region in the first direction within the ion channel toward the third region. During a release mode of operation, the third voltage signal can be applied and the second electric field can be generated.

[0032] In some embodiments, the first voltage signal can be a traveling wave. In other embodiments, the second voltage signal can be a DC voltage. In such embodiments, the magnitude of the DC voltage can be greater than the voltage bias of the first voltage signal. In other such embodiments, the third voltage signal can be a traveling wave, and the method can involve separating ions based on mobility with the traveling wave. In yet other such embodiments, the second voltage signal can be applied to a single electrode in the second region.

[0033] In other embodiments, the magnitude of the DC voltage can be less than the voltage bias of the first voltage signal, and the DC voltage can create a potential well. In such embodiments, the third voltage signal can be a DC potential gradient or a traveling wave. When the third voltage signal is a traveling wave, the method can further involve separating ions based on mobility by the traveling wave. In such embodiments, a DC voltage can be applied to two or more electrodes in the second region.

[0034] In yet other aspects, the second voltage signal can be a traveling wave traveling in a second direction opposite the first direction, and the third voltage signal can be a second traveling wave traveling in the first direction. In such aspects, the method can further involve separating ions based on mobility with the traveling wave. Additionally, in such aspects, the second voltage signal can be applied during a capture mode of operation, and the third voltage signal can be applied during a release mode of operation.

[0035] In one embodiment, the method can also involve transferring ions accumulated in the second region to a third region. The method can also involve applying a fourth voltage signal by the controller to a plurality of electrodes in the third region, the plurality of electrodes in the third region can be disposed on the first surface and can be disposed along the first longitudinal direction. The method can further involve generating a second driving potential by the plurality of electrodes in the third region, the second driving potential traveling along the first longitudinal direction. The second driving potential can be configured to guide the ions in the ion channel in the first longitudinal direction. The method can also involve separating the ions based on mobility by the second driving potential. In some embodiments, the fourth voltage signal and the third voltage signal can be the same. In other embodiments, the first voltage signal, the third voltage signal, and the fourth voltage signal can be the same.

[0036] The ion storage device includes an ion storage section, an exit section, and an exit transition section. The ion storage section has a first width and is configured to receive ions and switch between a first state and a second state to generate a first electric field when in the first state and a second electric field when in the second state. The exit section has a second width smaller than the first width and is configured to generate a third electric field configured to guide ions across the exit section. The exit transition section extends between the ion storage section and the exit section and has a tapered width that decreases from a first width adjacent the ion storage section to a second width adjacent the exit section. The exit transition section is also configured to generate a third electric field to guide ions across the exit transition section to the exit section. The first electric field is configured to prevent ions from moving in a first direction into the exit transition section, and the second electric field is configured to guide ions in the first direction toward the exit transition section. When the ion accumulation section is in the first state, the first electric field prevents ions in the ion accumulation section from exiting the ion accumulation section and causes the ions to accumulate in the ion accumulation section, and when the ion accumulation section is in the second state, the second electric field moves the ions in a first direction toward the exit transition section.

[0037] In some embodiments, the exit transition section can be configured to prevent ions from being ejected due to space charge effects. In some other embodiments, the third electric field can be the same as the second electric field or can be different from the second electric field.

[0038] In yet other embodiments, the ion storage device can also include an entrance section and an entrance transition section. The entrance section can have a third width less than the first width, and the entrance transition section can extend between the entrance section and the ion storage section. The entrance transition section can have a tapered width that increases from the third width adjacent the entrance section to the first width adjacent the ion storage section. In such embodiments, the entrance section and the exit transition section can be configured to generate a fourth electric field to guide ions across the entrance section and the entrance transition section to the ion storage section.

[0039] In some other aspects, the second electric field can be a traveling wave traveling in a first direction, and the ion accumulation section can be configured to be switched from generating the second electric field to generate a fourth electric field that is a traveling wave traveling in a second direction opposite the first direction.

[0040] In other embodiments, the first electric field can be a DC voltage. In such embodiments, a first portion of the ion accumulation section can generate the first electric field and a second portion of the ion accumulation section can generate a fourth electric field that is different from the first electric field.

[0041] In yet other embodiments, the ion accumulation section can include a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes. In such embodiments, the first electric field can be generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays.

[0042] In another aspect, the ion storage device can include an entrance section laterally positioned to the ion storage section, the entrance section configured to provide ions to the ion storage section.

[0043] Other configurations will become apparent from the following detailed description considered in conjunction with the accompanying drawings, which drawings, however, are designed for illustrative purposes only and not for defining the limits of the invention.

[0044] The above features of the present disclosure will become apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0045] [Figure 1] FIG. 1 is a schematic diagram of an exemplary ion mobility separation (IMS) system of the present disclosure. [Diagram 2] 2 is a schematic diagram of a portion of an exemplary SLIM device that can be used with the IMS system of FIG. 1 of the present disclosure. [Diagram 3] 3 is a schematic diagram illustrating a first exemplary arrangement of electrodes on a surface of the SLIM device of FIG. 2. [Figure 4] 3 is a schematic diagram illustrating a second exemplary arrangement of electrodes on the surface of the SLIM device of FIG. 2. [Diagram 5] 3 is a block diagram showing an example region of the SLIM device of FIG. 2. [Figure 6] FIG. 6 is a schematic block diagram illustrating a first set of exemplary waveforms applied to the exemplary region of FIG. 5 including a high DC potential waveform to accumulate ions. [Figure 7A] FIG. 6 is a schematic block diagram illustrating a second set of exemplary waveforms and a first release state waveform applied to the exemplary region of FIG. 5 including a DC potential well to accumulate ions. [Figure 7B] FIG. 7B is a schematic block diagram illustrating the second set of example waveforms shown in FIG. 7A along with a second released state waveform. [Figure 8] FIG. 6 is a schematic block diagram illustrating a third set of exemplary waveforms applied to the exemplary region of FIG. 5 including opposing traveling waves to accumulate ions. [Figure 9] FIG. 2 is a block diagram illustrating an exemplary arrangement of regions in an IMS system of the present disclosure for storing and separating ions. [Figure 10] 1 is a schematic diagram of an exemplary accumulation region of the present disclosure. [Figure 11] FIG. 11 is a schematic diagram of the exemplary accumulation region of FIG. 10 having a lateral inlet section. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] The present disclosure relates to methods and apparatus for internal trapping and storage of ions, as described in detail below in conjunction with FIGS.

[0047] Ions can be separated based on their mobility via ion mobility spectrometry (IMS). Mobility separation can be achieved, for example, by applying one or more potential waveforms (e.g., traveling potential waveforms, direct current (DC) gradients, or both) to a group of ions. IMS-based mobility separation can be achieved by structures for lossless ion manipulation (SLIM) that can systematically apply traveling and / or DC potential waveforms to a group of ions, such as the devices disclosed and described in U.S. Pat. No. 8,835,839, entitled "Method and Apparatus for Ion Mobility Separations Utilizing Alternating Current Waveforms," ​​and U.S. Pat. No. 10,317,364, entitled "Ion Manipulation Device," both of which are incorporated herein in their entirety. As a result, a continuous stream of ions can be separated in time / space based on their mobility. In some implementations, it is desirable to select ions having a predetermined mobility range from a group of ions. This can be achieved by mobility-based filtering of ions in a SLIM device ("SLIM filter"). A SLIM filter (e.g., low pass, high pass, band pass, etc.) can be applied superposition to multiple potential waveforms induced (e.g., traveling) in different directions (e.g., two dimensions). The characteristics of the potential waveforms (e.g., amplitude, shape, frequency, etc.) can determine the characteristics of the SLIM filter (e.g., bandwidth, cutoff mobility value, etc.).

[0048] The present disclosure utilizes the above-described SLIM devices to transmit and separate ions of different mobility, as well as to accumulate ions within the respective SLIM devices for subsequent separation and analysis. In this regard, as discussed in more detail below, different waveforms can be applied to different regions of the SLIM device, e.g., one or more electrodes grouped together, to trap ions within the accumulation region until a space charge limit is reached or a sufficient number of ions have accumulated.

[0049] FIG. 1 is a schematic diagram of an exemplary ion mobility separation (IMS) system 100 according to the present disclosure. The IMS system 100 includes an ionization source 102, a SLIM device 104, a mass spectrometer 106, a controller 108, a computing device 110, a power supply 112, and a vacuum system 114. The ionization source 102 generates ions (e.g., ions having varying mobilities and mass-to-charge ratios) and injects the ions into the SLIM device 104 (discussed in more detail in connection with FIGS. 2-4). The SLIM device 104 can be configured to transmit ions, accumulate ions, store ions, and / or separate ions, depending on the desired function and the waveforms applied. In this regard, the SLIM device 104 can be used to select ions having one or more predetermined mobility ranges and direct the selected ion band (or bands) to a detector, such as a mass spectrometer 106. The vacuum system 114 can be in fluid communication with the SLIM device 104 to regulate the gas pressure within the SLIM device 104. Specifically, the vacuum system 114 can provide nitrogen to the SLIM device 104 while maintaining the pressure within the SLIM device 104 at a consistent pressure.

[0050] The SLIM device 104 can include one or more surfaces 114a, 114b (e.g., printed circuit board surfaces) and can have multiple electrodes disposed on the one or more surfaces 114a, 114b. The electrodes can receive voltage signals, voltage waveforms, and / or current waveforms (e.g., DC, RF, or AC voltages or currents, or superpositions thereof) to generate electrical potentials (e.g., electrical potential gradients) to confine ions within the SLIM device 104, store ions within the SLIM device 104, and guide ions through the SLIM device 104, so that ions can be stored and separated based on their mobility, as discussed in more detail below.

[0051] The controller 108 can control the operation of the ionization source 102, the SLIM device 104, the mass spectrometer 106, and the vacuum system 114. For example, the controller 108 can control the rate of injection of ions into the SLIM device 104 by the ionization source 102, the threshold mobility of the SLIM device 104, and ion detection by the mass spectrometer 106. The controller 108 can also control the characteristics and dynamics of the potential waveforms generated by the SLIM device 104 to transmit, store, and / or separate ions (e.g., by applying RF / AC / DC potentials to electrodes of the SLIM device 104).

[0052] The controller 108 can control the characteristics of the potential waveform (e.g., amplitude, shape, frequency, etc.) by varying the characteristics of the applied RF / AC / DC potential (or current). In this regard, the controller 108 can vary the characteristics of the potential waveform for different regions of the SLIM device 104, e.g., different groups of electrodes, to trap / store and later separate ions. This can be done to increase ion peak resolution, narrow ion peaks, increase signal-to-noise ratio, and provide sharp separation before and after targeted mobilities.

[0053] The controller 108 can receive power from a power source 112, which can be, for example, a DC power source that provides a DC voltage to the controller 108. The controller 108 can include multiple power supply modules (e.g., current and / or voltage supply circuits) that generate various voltage (or current) signals that drive the electrodes of the SLIM device 104. For example, the controller 108 can include an RF control circuit that generates an RF voltage signal, a traveling wave control circuit that generates a traveling wave voltage signal, a DC control circuit that generates a DC voltage signal, etc. The RF voltage signal, the traveling wave voltage signal, and the DC voltage signal can be applied to the electrodes of the SLIM device 104. The controller 108 can also include a master control circuit that can control the operation of the RF / traveling wave / DC control circuit. For example, the master control circuit can control the amplitude and / or phase of the voltage (or current) signal generated by the RF / traveling wave / DC control circuit to achieve a desired operation of the mobility filter system 100.

[0054] As discussed above, the SLIM device 104 can generate DC / traveling potential waveforms (e.g., resulting from potentials generated by multiple electrodes in the SLIM device 104) and DC potentials to perform mobility-based separation and cause ion accumulation. The traveling potential waveforms can travel at a predetermined rate, for example, based on the frequency of the voltage signals applied to the electrodes. In some implementations, the traveling potential waveforms can have a spatial periodicity, which can depend on the phase difference between the voltage signals applied to adjacent electrode pairs. In some implementations, the phase difference determines the direction of propagation of the potential waveform. In some implementations, the waveforms applied to the accumulation / trapping / gate electrodes can control the accumulation of ions in the SLIM device 104. The master control circuit can control the frequency and / or phase of the voltage output of the RF / traveling wave / DC control circuitry such that the traveling potential waveforms have a desired (e.g., predetermined) spatial periodicity and / or rate, and the accumulation waveforms / potentials sufficiently restrict ion motion and therefore accumulate ions.

[0055] In some implementations, the controller 108 can be communicatively coupled to the computing device 110. For example, the computing device 110 can provide operational parameters of the IMS system 100 to the master control circuitry via control signals. In some implementations, a user can provide the operational parameters to the computing device 110 (e.g., via a user interface). Based on the operational parameters received via the control signals, the master control circuitry can control the operation of the RF / AC / DC control circuitry, which can determine the operation of the coupled SLIM device 104. In some implementations, the RF / AC / DC control circuitry can be physically distributed throughout the IMS system 100. For example, one or more of the RF / AC / DC control circuits can be located within the IMS system 100, and the various RF / AC / DC control circuits can operate based on power from the power source 112.

[0056] 2 is a schematic diagram of a portion of an exemplary SLIM device 104 (e.g., a SLIM device for ion transmission, ion accumulation, ion storage, and / or ion separation) that can be used with the IMS system 100 of FIG. 1. The SLIM device 104 includes a first surface 114a and a second surface 114b. The first and second surfaces 114a, 114b can be arranged (e.g., parallel to one another) to define one or more ion channels between the first and second surfaces 114a, 114b. The first and second surfaces 114a, 114b can include electrodes 116, 118a-f, 120a-e, 122a-x (see FIGS. 3 and 4), which are arranged, for example, as an array of electrodes on the surfaces facing the ion channels. The electrodes 116, 118a-118f, 120a-e, 122a-x on the first surface 114a and the second surface 114b can be electrically coupled to the controller 108 and can receive voltage (or current) signals or waveforms from the controller 108. In some implementations, the backside of the first surface 114a and the second surface 114b can include multiple conductive channels that enable electrical connections between the controller 108 and the electrodes 116, 118a-f, 120a-e, 122a-x on the first surface 114a and the second surface 114b. In some implementations, the number of conductive channels can be less than the number of electrodes 116, 118a-f, 120a-e, 122a-x. In other words, multiple electrodes 116, 118a-f, 120a-e, 122a-x can be connected to a single electrical channel. As a result, a given voltage (or current) signal can be transmitted simultaneously to multiple electrodes 116, 118a-f, 120a-e, 122a-x. Based on the received voltage (or current) signal, the electrodes 116, 118a-f, 120a-e, 122a-x can generate one or more electrical potentials (e.g., a superposition of various electrical potentials) that can confine, drive, and / or separate ions along an axis of propagation (e.g., the z-axis).

[0057] 3 is a schematic diagram illustrating a first exemplary arrangement of electrodes 116, 118a-f, 120a-e, 122a-h on first and second surfaces 114a, 114b of a SLIM device 104. It should be understood that the first and second surfaces 114a, 114b may be substantially mirror images with respect to a parallel plane, and thus the description of the first surface 114a applies equally to the second surface 114b, and thus the second surface 114b may also include electrodes having an electrode arrangement similar to the first surface 114a.

[0058] The first surface 114a includes a guard electrode 116, a plurality of continuous electrodes 118a-f, and a plurality of segmented electrode arrays 120a-e. Each of the plurality of continuous electrodes 118a-f can receive a voltage (or current) signal or can be connected to a ground potential to generate a pseudopotential that can prevent or inhibit ions from approaching the first surface 114a. The plurality of continuous electrodes 118a-f can be rectangular in shape, with the long side of the rectangle disposed along the propagation direction of the ions undergoing mobility separation, for example along a propagation axis parallel to the z-axis shown in FIG. 3. The plurality of continuous electrodes 118a-f can be separated from each other along a lateral direction, for example along the y-axis, that can be orthogonal to the propagation direction, for example the z-axis.

[0059] Each of the plurality of segmented electrode arrays 120a-e can be disposed between two continuous electrodes 118a-f and includes a plurality of individual electrodes 122a-h, e.g., 8 electrodes, 16 electrodes, 24 electrodes, etc., disposed along the propagation direction (parallel to the propagation direction), e.g., along the z-axis. It should be understood that each segmented electrode array 120a-e can include more than 9 or less than 7 electrodes, but should include at least 3 electrodes. For example, as shown in FIG. 4, the segmented electrode arrays 120a-e each include 24 electrodes 122a-x. In addition, the individual electrodes 122a-x can be separated into individual groups that receive unique signals from the controller 108, as discussed in more detail below. The plurality of segmented electrode arrays 120a-e can receive a second voltage signal and generate a drive potential that can drive ions along the propagation axis, or a DC voltage signal that can trap ions, as discussed in more detail below. That is, the first and second surfaces 114a, 114b and their electrode arrangements may be implemented for different purposes and therefore have different functions based on the voltage settings applied to the continuous electrodes 118a-f, the segmented electrode arrays 120a-e, and the plurality of individual electrodes 122a-h.

[0060] The plurality of continuous electrodes 118a-f and the plurality of segmented electrode arrays 120a-e may be arranged alternately on the first surface 114a between the DC guard electrode 116. The segmented electrode arrays 120a-e may be traveling wave (TW) electrodes such that each of the individual electrodes 122a-h of each segmented electrode array 120a-e receives a voltage signal that is applied to all individual electrodes 122a-h simultaneously but out of phase between adjacent electrodes 122a-h along the z-axis. However, the same individual electrode of the segmented electrode arrays 120a-e, e.g., the first individual electrode 122a, receives the same voltage signal without phase shift.

[0061] The voltage signals applied to the individual electrodes 122a-h can be sinusoidal (e.g., AC voltage waveform), rectangular waveform, DC square waveform, sawtooth waveform, biased sinusoidal waveform, pulsed current waveform, etc., and the amplitude of the signal provided to the individual electrodes 122a-h can be determined based on the applied voltage waveform, for example, taking into account the phase shift described above. For example, if a single wavelength of the AC voltage waveform extends across eight electrodes (e.g., individual electrodes 122a-h), the amplitude of the voltage signal applied to the individual electrodes 122a-h can be determined by selecting a value from the AC waveform for a phase shift that corresponds to the total number of electrodes associated with the single wavelength (e.g., eight electrodes). For example, the phase shift between adjacent electrodes of the individual electrodes 122a-h is 45 degrees (360 degrees of a single wavelength cycle divided by 8). This can be achieved by electrically coupling the individual electrodes 122a-h to different traveling wave control circuits, e.g., AC control circuits, DC (square wave) control circuits, pulsed current control circuits, etc., that generate voltage signals that are out of phase with each other. Alternatively, the controller 108 can be a single traveling wave control circuit capable of generating voltage signals that can be simultaneously applied to the electrodes 122a-h. It should be understood that the voltage or current waveforms can be of various shapes, e.g., square, triangular, rectangular, sawtooth, etc., and can be periodic, non-periodic, etc. For example, the controller 108 can be a traveling wave control circuit and can include one or more DC (square wave) control circuits that generate DC voltage signals and an AC control circuit that generates a sinusoidal signal.

[0062] As described above, the controller 108 can include one or more pulse voltage or current control circuits capable of generating pulse voltage (or current) waveforms, e.g., square, triangular, rectangular, sawtooth, etc. The pulse voltage (or current) waveforms can be periodic without polarity reversal. The pulse voltage (or current) control circuit can include multiple outputs electrically connected to the individual electrodes 122a-h. In some implementations, the controller 108 can be a pulse voltage (or current) control circuit capable of simultaneously applying multiple voltage signals (e.g., constituting a pulse waveform) to each of the individual electrodes 122a-h. Various pulse shapes of the voltage (or current) waveforms can be generated by superposition of DC voltage signals and sinusoidal signals. The controller 108 can determine a phase shift between the voltage signals generated by the various traveling wave control circuits. The shape / periodicity of the traveling potential waveform can be based on the phase shift between the voltage signals applied to adjacent electrodes 122a-h. The controller 108 can determine the amplitude of the DC voltage signal generated by the DC control circuit and can determine the amplitude and / or frequency of the AC signal generated by the traveling wave control circuit.

[0063] The frequency of the voltage signal (e.g., AC signal) can determine the speed of the traveling potential waveform. An alternative approach to generating out-of-phase AC signals for the voltage (or current) waveforms that generate the traveling potential waveform is to use a multi-phase transformer. This approach can provide control of the phase relationship between multiple voltage output signals based on the connection scheme of multiple secondary windings of the transformer. In this way, multiple phase-dependent outputs can be generated by analog circuitry alone using one or more input drive voltage signals. The main difference between this approach and the digital generation methods described above is that the phase dependence can be determined by the physical wiring of the transformer, and this phase dependence cannot be changed without making physical changes to the wiring. The phase relationship between digitally generated waveforms can be dynamically varied without hardware changes.

[0064] Over time, the potential waveform (e.g., generated by an AC waveform, a sinusoidal voltage waveform, a pulsed voltage [or current] waveform applied to the electrodes) can progress along the propagation direction, e.g., along the z-axis. This can result in a change in the amplitude of the voltage applied to the individual electrodes 122a-h. For example, a voltage applied to a first individual electrode 122a during a first time step is applied to an adjacent individual electrode 122b during the next time step. The controller 108 can include one or more traveling wave control circuits capable of generating pulsed voltage / current waveforms, AC waveforms, etc. In some implementations, the controller can include one or more RF control circuits capable of generating RF voltage waveforms, as discussed in more detail below.

[0065] The controller 108 can control the speed of the traveling potential waveform by controlling the frequency and / or phase of the AC / RF / pulsed voltage (or current) waveform applied to the individual electrodes 122a-h. If desired, as the potential waveform travels, ions introduced into the SLIM device 104 can be pushed along a direction of propagation and, optionally, separated along the z-axis based on their mobility. In this regard, the traveling waveform applied by the controller 108 can be used to transmit ions without separating them, or to transmit ions and separate them based on their mobility during transmission.

[0066] As described above, the plurality of continuous electrodes 118a-f may be connected to one or more voltage control circuits, such as a voltage control circuit in the controller 108, from which they may receive RF signals. The RF voltages applied to the continuous electrodes 118a-f may be out of phase with respect to adjacent continuous electrodes 118a-f. That is, adjacent continuous electrodes 118a-f may receive the same RF signal, but out of phase by 180 degrees. Accordingly, in a first state, the first, third, and fifth electrodes 118a, 118c, 118e may have a positive polarity (denoted as RF+), and the second, fourth, and sixth continuous electrodes 118b, 118d, 118f may have a negative polarity (denoted as RF-). As time and signals progress, the polarity of each of the continuous electrodes 118a-f is switched. The above functions to retain ions between the first and second surfaces 114a, 114b and prevent ions from contacting the first and second surfaces 114a, 114b.

[0067] As discussed above, SLIM device 104 can have more than nine or less than seven individual electrodes 122a-h in each of segmented electrode arrays 120a-e, and can include more than six or less than four segmented electrode arrays 120a-e and six continuous electrodes 118a-f, depending on the desired functionality of SLIM device 104. For example, Figure 4 is a schematic diagram illustrating second and third exemplary arrangements of electrodes 116, 118a-f, 120a-e, 122a-x on first and second surfaces 114a, 114b of SLIM device 104. More specifically, the arrangement of electrodes 116, 118a-f, 120a-e, 122a-x shown in FIG. 4 is substantially the same as the arrangement shown in FIG. 3, but with 24 individual electrodes 122a-x for each segmented electrode array 120a-e, the six continuous electrodes 118a-f are divided into three sets, and the guard electrode 116 is divided into three sets.

[0068] In this configuration, the first set of eight individual electrodes 122a-h can be used for a first function, e.g., to transmit ions with or without separating ions, the second set of eight individual electrodes 122i-p can be used for a second function, e.g., to trap and store ions, and the third set of eight individual electrodes 122q-x can be used for a third function, e.g., to transmit ions while separating ions. For example, the controller 108 can provide a first waveform to the first set of eight individual electrodes 122a-h, a second waveform to the second set of eight individual electrodes 122i-p, and a third waveform to the third set of eight individual electrodes 122q-x. Additionally, depending on the desired function, each of the individual electrodes 122a-x can be individually controlled by the controller 108 to provide a waveform or voltage (e.g., a DC voltage value) or to switch between different waveforms or voltages. Accordingly, if necessary, the individual electrodes 122a-x may be divided into groups according to design considerations.

[0069] FIG. 5 is a block diagram illustrating exemplary regions of the SLIM device 104 of FIG. 2, and as shown in FIG. 5, the individual electrodes 122a-x can be grouped into different regions based on their desired functions. For example, the SLIM device 104 can include a transfer region 124, an accumulation region 126, and a separation region 128. The transfer region 124 can be applied with a traveling wave that transfers ions to the accumulation region 126. The accumulation region 126 can capture and store ions, for example, by implementation of one or more switching / gate electrodes. The separation region 128 can separate and transfer ions released from the accumulation region 126. The electrode arrangement shown in FIG. 3 can be implemented in any of the transfer, accumulation, and separation regions 124, 126, 128, with the voltages applied to the respective electrodes determining the functions. For example, a first set of eight individual electrodes 122a-h in FIG. 4 may be implemented as a transfer region 124, a second set of eight individual electrodes 122i-p in FIG. 4 may be implemented as an accumulation region 126, and a third set of eight individual electrodes 122q-x in FIG. 4 may be implemented as an isolation region 128.

[0070] 4 and 5, the accumulation region 126 may be provided with a separate set of continuous electrodes 118a-f and a separate set of guard electrodes 116, which may be individually controlled and different voltages may be applied to the electrodes by the controller 108. This configuration allows different RF and DC voltages to be applied to the accumulation region 126. For example, the amplitude of the RF voltage applied to the continuous electrodes 118a-f in the accumulation region 126 may be reduced to avoid exciting ions, and the RF voltage applied to the continuous electrodes 118a-f in the accumulation region 126 and the DC guard voltage applied to the guard electrodes 116 in the accumulation region 126 may be adjusted to match the voltages applied to the second set of individual electrodes 122i-p in the accumulation region 126.

[0071] 6 is a schematic block diagram illustrating a first set of exemplary waveforms applied to regions 124, 126, 128 of SLIM device 104 and exemplary ion motion through regions 124, 126, 128. A first traveling wave 130 is applied to transmission region 124 to transmit ions 132a-c along a propagation axis, e.g., the z-axis, to accumulation region 126. The first traveling wave 130 can be generated by controller 108 and customized to transmit ions 132a-c with or without separating ions 132a-c based on mobility. Transmission region 124 can include multiple individual electrodes 122a-x of each segmented electrode array 120a-e. For example, first through eighth individual electrodes 122a-h for all segmented electrode arrays 120a-e can receive the first traveling wave 130 and transmit ions 132a-c to accumulation region 126. As the first traveling wave 130 extends into the accumulation region 126 , the accumulation region 126 can partially overlap the transfer region 124 .

[0072] The accumulation region 126 can have two different states / modes of operation, e.g., a trapping state and a releasing state, i.e., can operate for different time periods. When in the trapping state / mode of operation, the first traveling wave 130 can extend into the accumulation region 126, and a signal applied to a single gate electrode 131, e.g., the first individual electrode 122a of each segmented electrode array 120a-e in the isolation region 128 (e.g., the seventeenth individual electrode 122q in FIG. 4), or the eighth individual electrode 122h of each segmented electrode array 120a-e in the accumulation region 126 (e.g., the sixteenth individual electrode 122p in FIG. 4), can be switched from the first traveling wave 130 to a signal configured to trap the ions 132a-c or prevent the ions 132a-c from continuing to propagate. More specifically, the gate electrode receives a high DC potential voltage signal 134 from the controller 108, the potential of which is greater than the voltage bias of the first traveling wave 130. The voltage bias of the first traveling wave 130 is generally a fixed DC voltage applied to the first traveling wave 130 to shift the waveform. Thus, the first traveling wave 130 continuously transmits the ions 132a-c provided to the SLIM device 104, e.g., from the ionization source 102 along the propagation axis until the ions 132a-c reach the gate electrode 131, at which point the ions 132a-c are stopped, e.g., repelled, by the high DC potential voltage signal 134. Nevertheless, the continuously circulating first traveling wave 130 prevents the ions 132a-c from propagating in the opposite direction, e.g., in the negative z-axis direction, and instead captures the ions 132a-c from the high DC potential voltage signal 134 by continuously pushing the ions 132a-c in the propagation direction, e.g., in the positive z-axis direction, thereby allowing the ions 132a-c to accumulate in the accumulation region 126. This essentially packets the ions 132 a - c and therefore allows them to be separated together within the separation region 128 .

[0073] Accordingly, in operation, when in a trapping state / mode of operation, ions 132a-c may be continuously delivered to the SLIM device 104 until a sufficient number of ions are accumulated, which may be determined by whether a space charge limit is reached. More specifically, space charge effects limit the maximum number of charges that can be accommodated in a given length before the ions are released. Generally, the space charge limit is approximately 1 million charges per millimeter of path length in the SLIM device 104. Accordingly, a single traveling wave segment, e.g., an electrode segment as shown and described in connection with FIG. 3 including six RF electrodes 118a-f and five segmented electrode arrays 120a-e having eight individual electrodes 122a-h, may be used to accumulate ions, the segment being, e.g., 9 millimeters long, with a space charge limit (e.g., accumulation capacity) of approximately 9 million charges. That is, 9 million charges may be accumulated before the space charge limit is exceeded, at which point ions may be lost from the trap. It should be noted that the space charge limit is based on the total charge value of all ions stored, not the number of ions. For example, some ions may have a larger charge value, e.g., +40 or +50, and in such a situation, fewer ions should be stored than if ions with a charge of +10 were stored. Furthermore, while the above assumes a single traveling wave segment having six RF electrodes 118a-118f and five segmented electrode arrays 120a-e, if additional capacity is required, e.g., to increase the sensitivity of the analysis, additional rows can be added to increase the storage capacity per unit length. For example, a sixth segmented electrode array and an eighth continuous RF electrode could be added to the electrode configuration shown in Figures 3 and 4, which would provide additional space for ion storage.

[0074] The gate electrode 131 may be a switchable electrode and may thus operate in a trapping state for a first period of time until a sufficient number of ions are accumulated, and then the signal applied to the gate electrode 131 may be switched to a release state and the gate electrode 131 may operate in the release state for a second period of time. For example, the signal may be switched from a high DC potential voltage signal 134 to a second traveling wave 136, thus releasing the accumulated ions 132a-c into the separation region 128 in synchronism with the second traveling wave 136 applied to the separation region 128. The second traveling wave 136 may be generated by the controller 108 and applied to the electrodes of the separation region 128 to separate the ions 132a-c based on their mobility along the z-axis and push the ions 132a-c in a propagation direction, e.g., along the z-axis, towards the mass spectrometer 106 for analysis. The separation region 128 may include multiple individual electrodes 122a-x of each of the segmented electrode arrays 120a-e. For example, the seventeenth through twenty-fourth individual electrodes 122q-x (see FIG. 4) for all segmented electrode arrays 120a-e may receive the second traveling wave 136. Note that the transmission region 124 may also function as a separation region, such that the first traveling wave 130 is the same as the second traveling wave 136, thereby assisting in synchronizing the first and second traveling waves 130, 136 when switching between captured and released states / modes of operation.

[0075] Figure 7A is a schematic block diagram illustrating a second set of exemplary waveforms applied to regions 124, 126, 128 of SLIM device 104, including a first released state waveform (released states 1A and 1B), and exemplary ion motion through regions 124, 126, 128. Figure 7B is a schematic block diagram illustrating the second set of exemplary waveforms as shown in Figure 7A with a second released state waveform.

[0076] As described above, the first traveling wave 130 is applied to the transfer region 124 to transfer the ions 132a-c along a propagation axis, e.g., the z-axis, to the accumulation region 126. The first traveling wave 130 can be generated by the controller 108 and can be customized to transfer the ions 132a-c with or without separating the ions 132a-c based on mobility. The transfer region 124 can include multiple individual electrodes 122a-x of each segmented electrode array 120a-e. For example, the first through eighth individual electrodes 122a-h for all segmented electrode arrays 120a-e can receive the first traveling wave 130 and transfer the ions 132a-c to the accumulation region 126. Because the first traveling wave 130 extends into the accumulation region 126, the accumulation region 126 can overlap the transfer region.

[0077] The accumulation region 126 can have two different states / modes of operation, e.g., a trapping state / mode and a releasing state / mode of operation, i.e., can operate for different time periods. When in the trapping state / mode of operation, the first traveling wave 130 can extend into the accumulation region 126 and a signal applied to the multiple gate / trapping electrodes can be switched from the first traveling wave 130 to a signal configured to trap the ions 132a-c or prevent the ions 132a-c from continuing to propagate. For example, two electrodes may be implemented as gate / capture electrodes, such as the first and second individual electrodes 122a, 122b (e.g., the ninth and tenth individual electrodes 122i, 122j of FIG. 4) of each segmented electrode array 120a-e (see FIG. 3) in the accumulation region 126, or the seventh and eighth individual electrodes 122g, 122h (e.g., the fifteenth and sixteenth individual electrodes 122o, 122p of FIG. 4) of each segmented electrode array 120a-e (see FIG. 3) in the accumulation region 126, or the entire array of individual electrodes 122a-h (e.g., the ninth through sixteenth individual electrodes 122i-p of FIG. 4) of each segmented electrode array 120a-e (see FIG. 3) in the accumulation region 126.

[0078] More specifically, the gate / trap electrodes (e.g., seventh and eighth electrodes 122g, 122h) receive a low DC potential voltage signal 140 from the controller 108 for a first time period, thereby creating a potential well (e.g., a DC potential well) that is lower in potential than the voltage biases of the first traveling wave 130 and second traveling wave 142 in the separation region 128. Thus, the first traveling wave 130 continues to transmit ions 132a-c, e.g., provided to the SLIM device 104 from the ionization source 102, along the propagation axis until the ions 132a-c reach the gate / trap electrodes 122g, 122h, where the ions 132a-c are trapped because they are no longer able to overcome the potential of the second traveling wave 142 in the separation region 128. Similarly, the continuously circulating first traveling wave 130 prevents the ions 132a-c from propagating in the opposite direction, e.g., the negative z-axis direction, and traps the ions 132a-c in the low potential well 140, thereby accumulating the ions 132a-c in the accumulation region 126, e.g., in the low potential well 140. This essentially packets the ions 132a-c, so that they can be separated collectively in the separation region 128.

[0079] Accordingly, in operation, when in a trapping state / mode of operation, ions 132a-c can be continuously pumped into the SLIM device 104 until a sufficient number of ions are accumulated in the low potential well 140 and accumulation region 126, which can be determined by whether a space charge limit is reached, as discussed above. However, since the accumulation region 126, e.g., the low potential well 140, extends across multiple electrodes, the capacity of the trap can be controlled, since more than two electrodes can be used to create a low potential well and accumulate a larger number of ion charges. Furthermore, if additional capacity is required, e.g., to increase the sensitivity of the analysis, additional rows can be added to increase the storage capacity per unit length. For example, a sixth segmented electrode array and an eighth continuous RF electrode can be added to the electrode configuration shown in Figures 3 and 4, which would provide additional space for ion accumulation.

[0080] The gate / trap electrodes 122g, 122h may be switchable electrodes, such that after a sufficient number of ions have been accumulated, the signal applied to the gate / trap electrodes 122g, 122h may be switched to a release state. For example, as shown by the release state 1A in FIG. 7A, the signal applied to the gate / trap electrodes 122g, 122h may be switched from a low DC potential voltage signal 140 to a ramping DC potential voltage signal 144 (e.g., a DC potential gradient) traveling across the gate / trap electrodes 122g, 122h with decreasing potential to push the accumulated / trapped ions 132a-c towards the separation region 128, thereby releasing the accumulated ions 132a-c into the separation region 128. The second traveling wave 142 can be generated by the controller 108 and applied to the separation region 128 and configured to communicate the ions 132a-c from the accumulation region 126 to the separation region 128 for propagation and separation in coordination or synchronization with the ramped DC potential voltage signal 144. The second traveling wave 142 separates the ions 132a-c based on their mobility along the z-axis and pushes the ions 132a-c along a propagation direction, e.g., along the z-axis, toward the mass spectrometer 106 for analysis. The separation region 128 can include multiple individual electrodes 122a-x of each segmented electrode array 120a-e. For example, the 17th through 24th individual electrodes 122q-x for all segmented electrode arrays 120a-e (see FIG. 4) can receive the second traveling wave 142. Note that the transmission region 124 can also function as a separation region, and thus the first traveling wave 130 is the same as the second traveling wave 136.

[0081] 7A by the released state 1B, the second traveling wave 142 can be offset from the first traveling wave 130, for example, a lower voltage bias can be applied to the second traveling wave 142 than that applied to the first traveling wave 130. In this configuration, the DC potential voltage signal 140 can be configured to transition downward from the voltage bias of the first traveling wave 130 to the voltage bias of the second traveling wave 142, pushing the ions 132a-132c from the accumulation region 126 to the separation region 128 for propagation and separation.

[0082] Instead of implementing a ramped DC potential voltage signal 144 during the released state / mode, the controller 108 can provide a third traveling wave 146 to the gate / trap electrodes 122g, 122h when in the released state / mode, as shown in Figure 7B, which illustrates a second released state waveform. That is, the signal provided to the gate / trap electrodes 122g, 122h can be switched from the low DC potential voltage signal 140 to the third traveling wave 146, which can be configured to coordinate or synchronize with the first traveling wave 130 and / or the second traveling wave 142 to push the accumulated / trapped ions 132a-c towards and into the separation region 128 when the second traveling wave 142 is applied. As discussed above, the second traveling wave 142 can be generated by the controller 108 and can be configured to coordinate or synchronize with the third traveling wave 146 to transfer the ions 132a-c from the accumulation region 126 to the separation region 128 for propagation and separation.

[0083] In addition, as described in connection with Fig. 4, the accumulation region 126 may be provided with a separate set of continuous electrodes 118a-f and a separate set of guard electrodes 116, which may be individually controlled and different voltages may be applied to them by the controller 108. This configuration allows different RF and DC voltages to be applied to the accumulation region 126. For example, when the accumulation region 126 is in a trapping state and thus receives a low DC potential voltage signal 140, the amplitude of the RF voltage applied to the continuous electrodes 118a-f in the accumulation region 126 may be reduced to avoid exciting ions, and the DC guard voltage applied to the guard electrodes 116 in the accumulation region 126 may be reduced to match the voltage applied to the individual electrodes 122i-p of the accumulation region 126 while remaining at a level that ensures that ions do not exit from these sides. Additionally, when accumulation region 126 is switched to the released state, the RF voltages applied to continuous electrodes 118a-f and the DC guard voltage applied to guard electrode 116 can be adjusted, which involves changing the voltage signals applied to individual electrodes 122i-p. For example, if the voltage signals applied to individual electrodes 122i-p are increased during the released state, the DC guard voltage applied to guard electrode 116 can be increased to ensure that ions do not escape out the side of SLIM device 104.

[0084] FIG. 8 is a schematic block diagram illustrating a third set of exemplary waveforms applied to exemplary regions 124, 126, 128 of the SLIM device 104 and exemplary ion motion through the regions 124, 126, 128. In particular, FIG. 8 demonstrates an implementation in which opposing traveling waves are used to trap and accumulate ions. As described above, a first traveling wave 130 is applied to the transfer region 124 to transfer ions 132a-c along a propagation axis, e.g., the z-axis, to the accumulation region 126. The first traveling wave 130 can be generated by the controller 108 and can be customized to transfer ions 132a-c with or without separating ions 132a-c based on mobility. The transfer region 124 can include multiple individual electrodes 122a-x of each of the segmented electrode arrays 120a-e. For example, the first through eighth individual electrodes 122a-h of every segmented electrode array 120a-e can receive the first traveling wave 130 and transmit ions 132a-c to the accumulation region 126.

[0085] Similarly, a second traveling wave 142 can be applied to the isolation region 128, and the second traveling wave 142 can be generated by the controller 108. The isolation region 128 can include a plurality of individual electrodes 122a-x of each segmented electrode array 120a-e. For example, the 17th to 24th individual electrodes 122q-x of all segmented electrode arrays 120a-e (see FIG. 4) can receive the second traveling wave 142. Thus, the second traveling wave 142 can begin when the first traveling wave 130 ends. In this regard, the second traveling wave 142 can be the same waveform as the first traveling wave 130, and thus these waveforms essentially form a single continuous wave.

[0086] However, the SLIM device 104 can have two different states / modes of operation, e.g., a trapped state / mode of operation and a released state / mode of operation, i.e., operate for different time periods. When in the trapped state / mode of operation, the controller 108 can apply a third traveling wave 148 traveling in a direction opposite to the first traveling wave 130, e.g., along the negative direction of the z-axis toward the first traveling wave 130, to the separation region, e.g., the 17th-24th individual electrodes 122q-x, for a period of time. Accordingly, the first traveling wave 130 and the third traveling wave 148 can be opposing waves that meet at the accumulation region 126. In addition, the third traveling wave 148 can have the same frequency and magnitude as the first traveling wave 130, but propagate in the opposite direction. In this configuration, the individual electrodes 122q-x of the separation region can be switchable such that the controller 108 applies the third traveling wave 148 to the individual electrodes 122q-x during the capture state / operational mode and the second traveling wave 142 during the release state / operational mode.

[0087] Thus, when the SLIM device 104 operates in a trapping state / mode of operation, the first traveling wave 130 continuously transmits the ions 132a-c provided to the SLIM device 104, e.g., from the ionization source 102, along a propagation axis until the ions 132a-c reach the accumulation region 126, e.g., a point between the eighth electrode 122h and the ninth electrode 122i, at which point the ions 132a-c are stopped by the opposing first and third traveling waves 130, 148. That is, the first traveling wave 130 pushes the ions 132a-c along the positive direction of the z-axis, and the second traveling wave 142 pushes the ions 132a-c in the opposite direction, which is the negative direction of the z-axis. Thus, the continuously circulating third traveling wave 148 prevents the ions 132a-c from propagating further across the SLIM device 104 along the z-axis, and the continuously circulating first traveling wave 130 transfers the ions 132a-c to the accumulation region 126 and then prevents the ions 132a-c from propagating along the z-axis in the opposite direction, e.g., the negative direction. The opposing first and third traveling waves 130, 148 prevent the ions 132a-c disposed within the accumulation region 126 from traveling a large distance along the z-axis, thus trapping the ions 132a-c and allowing the ions 132a-c to accumulate within the accumulation region 126. This essentially packets the ions 132a-c and therefore can be separated en masse within the separation region 128.

[0088] Accordingly, in operation, when in a trapping state / mode of operation, ions 132a-c can be continuously pumped into the SLIM device 104 until a sufficient number of ions are accumulated in the accumulation region 126, which can be determined by whether a space charge limit is reached, as discussed above. Furthermore, if additional capacity is required, e.g., to increase the sensitivity of the analysis, additional rows can be added to increase the accumulation capacity per unit length. For example, a sixth segmented electrode array and an eighth continuous RF electrode can be added to the electrode configuration shown in Figures 3 and 4, which would provide additional space for ion accumulation.

[0089] As mentioned above, the electrodes 122q-x in the separation region can be switchable electrodes, so that after a sufficient number of ions have accumulated, the signal applied to the electrodes 122q-x can be switched to a release state. For example, this signal can be switched from the third traveling wave 148 to the second traveling wave 142 to be synchronized with the first traveling wave 130 applied to the transfer region, thereby releasing the accumulated ions 132a-c into the separation region 128. The second traveling wave 136 can be generated by the controller 108 and applied to the separation region 128 to separate the ions 132a-c based on their mobility along the z-axis and push the ions 132a-c along a propagation direction, e.g., the z-axis, towards the mass spectrometer 106 for detection. It should be noted that the transfer region 124 can also function as a separation region such that the first traveling wave 130 is the same as the second traveling wave 136, thereby assisting in synchronizing the first and second traveling waves 130, 136 when switching between captured and released states / modes of operation.

[0090] FIG. 9 is a block diagram illustrating an exemplary arrangement of the transfer, accumulation, and separation regions 124, 126, 128 in the IMS system 100 of the present disclosure for accumulating and isolating ions. As shown in FIG. 9, the IMS system 100 can include multiple transfer, accumulation, and separation regions 128 to further increase resolution. It is noted that alternative arrangements and configurations are also contemplated by the present disclosure. In this regard, it is noted that the different regions 124, 126, 128 do not need to be arranged in a straight line. Instead, for example, the transfer region 124 can be arranged orthogonally to the accumulation or separation regions 126, 128. In addition, gates can be implemented by the present disclosure to control the flow of ions, for example, from the transfer region 124 to the accumulation region 126 or from the separation region 128 to the second accumulation region 126.

[0091] Figure 10 is a schematic diagram of an exemplary storage region 150 of the present disclosure that may be implemented, for example, as storage region 126 shown and described in connection with Figures 5-9. That is, it should be understood that the discussion of storage region 126 and its functionality, including the applied waveforms, trapping states, and release states discussed above, are equally applicable to storage region 150 shown in Figure 10.

[0092] The accumulation region 150 includes an entrance section 152, an entrance transition section 154, an ion accumulation section 156, an exit transition section 158, and an exit section 160. As discussed in more detail below, each of the sections 150-160 generally includes a plurality of rows of continuous electrodes 162 and a plurality of segmented electrode arrays 164, the number of which may vary among the sections 150-160. In this regard, as shown in FIG. 10, some of the rows of continuous electrodes 162 and segmented electrode arrays 164 may extend through two or more sections 150-160, and some may extend through all sections 150-160 of the accumulation region 150. The continuous electrodes 162 may be substantially similar to the continuous electrodes 118a-f illustrated and described in connection with FIGS. 3 and 4, and the segmented electrode arrays 164 may be substantially similar to the plurality of segmented electrode arrays 120a-e illustrated and described in connection with FIGS. 3 and 4. Like the segmented electrode arrays 120a-e, the segmented electrode array 164 may include a number of individual electrodes 122a-h. It should also be noted that for ease of illustration, not all of the continuous electrodes 162, the segmented electrode array 164, and the individual electrodes 122a-h are labeled in Figure 10, but instead a suitable representative number of elements are labeled.

[0093] The entrance section 152 and the exit section 160 may each include, for example, six rows of continuous electrodes 118a-f and five segmented electrode arrays 164. However, it should be understood that more or fewer rows and segmented electrode arrays may also be included. The entrance section 152 may be configured to receive ions from another section of the SLIM device 104, and the exit section 160 may be configured to provide ions to another section of the SLIM device 104. For example, the entrance and exit sections 152, 160 may be located adjacent to the transfer region 124, the separation region 128, the different accumulation regions 126, 150, or any other region of the SLIM device 104 to receive ions from or provide ions to that region. Accordingly, voltage signals, e.g., traveling wave voltage signals, applied to the individual electrodes 122a-h of the segmented electrode arrays 164 of the entrance section 152 and the exit section 160 may cooperate with voltage signals applied to adjacent sections of the SLIM device 104 to fully integrate and match these signals. It is also understood that the present disclosure contemplates at least one embodiment in which the entrance section 152 may additionally and / or alternatively be implemented as an outlet, and the exit section 160 may additionally and / or alternatively be implemented as an entrance. For example, the ion accumulation section 156 may be implemented not only for accumulating ions, but also as a switching region for selectively directing ions to the entrance section 152 (utilized as an outlet) or the exit section 160.

[0094] The inlet transition section 154 extends from the inlet section 152 to the ion accumulation section 156 and increases in width as it proceeds from the inlet section 152 to the ion accumulation section 156 along the z-axis. Accordingly, the width of the inlet transition section 154 along the y-axis is greater adjacent the ion accumulation section 156 compared to adjacent the inlet section 152. In addition, the number of rows of continuous electrodes 162 and segmented electrode arrays 164 gradually increases as the width of the inlet transition section 154 increases. Conversely, the outlet transition section 158 tapers and decreases in width as it proceeds from the ion accumulation section 156 to the outlet section 160 along the z-axis. Accordingly, the width of the outlet transition section 158 along the y-axis is greater adjacent the ion accumulation section 156 compared to adjacent the outlet section 160. In addition, the number of rows of continuous electrodes 162 and segmented electrode arrays 164 gradually decreases as the width of the outlet transition section 158 decreases.

[0095] The accumulation region 150 is designed such that the ion accumulation section 156 is wider, e.g., along a y-axis orthogonal to the ion propagation axis (z-axis in FIG. 10), than the entrance section 152, the exit section 160, and / or the other portions of the path through the SLIM device 104. The accumulation region 150 is also designed such that the entrance transition section 154 and the exit transition section 158 provide a gradual transition between the entrance and exit sections 152, 160 and the accumulation section 156. Accordingly, the accumulation section 156 includes more rows of electrodes, e.g., rows of continuous electrodes 162 and segmented electrode arrays 164, than the other portions of the path through the SLIM device 104. For example, as shown in FIG. 10, the accumulation section 156 can include 16 rows of continuous electrodes 162 and 15 segmented electrode arrays 164, while the entrance section 152 and the exit section 160 designed to interface with the other portions of the path through the SLIM device 104 include 6 rows of continuous electrodes 162 and 5 segmented electrode arrays 164.

[0096] In addition, the segmented electrode array 164 of the accumulation section 156 can be divided into multiple groups or segments, as described in connection with FIG. 5. For example, each segmented electrode array 164 of the accumulation section 156 can include three groups or segments of eight individual electrodes 122a-h (e.g., 24 electrodes). The number of segmented electrode array groups and / or the number of individual electrodes 122a-h per segmented electrode array group can be increased or decreased as required for the implementation and experiment. In addition, the individual electrodes 122a-h of the segmented electrode array 164 of the accumulation section 156 can receive traveling wave signals independently of the transition sections 154, 158, the entrance section 152, and the exit section 160, allowing the traveling wave direction, and therefore the ion traveling direction through the accumulation section 156, to be switched as required. It should also be understood that the accumulation region 150 can operate similarly to that shown and described in connection with FIGS. 6-8.

[0097] Additionally, each segmented electrode array 164 in the accumulation section 156 can have one or more gate electrodes 166, e.g., the eighth electrode 122h of the third segmented electrode array group, to which a signal can be applied to trap the ions 132a-c or prevent the ions 132a-c from continuing to propagate through the accumulation region 150. More specifically, the gate electrodes 166 can receive a high DC voltage signal from the controller 108 to generate a high DC electric field (V / m) to trap the ions within the accumulation section 156 when the ions are provided to the accumulation section 156 by the entrance section 152, the entrance transition section 154, and the individual electrodes 122a-h preceding the gate electrodes 166. The accumulated ions are also held laterally, e.g., in the y-axis, by DC guard electrodes 168, which flank the sections 152-160 of the accumulation region 150 and function in accordance with the guard electrodes 116 shown and described in connection with FIGS. 3 and 4. Increasing the width of the accumulation section 156 allows more ions to be held before space charge problems are encountered, compared to a narrower accumulation section, such as an accumulation section 156 that is the same width as the entrance section 152 or the remainder of the path through the SLIM device 104.

[0098] After a desired number of ions have been accumulated in the accumulation section 156, the high DC voltage signal can be removed and a traveling wave signal can be applied that cooperates with the traveling wave signal applied to the other individual electrodes 122a-h in the accumulation section 156 as well as the traveling wave signal applied to the exit transition section 158. After the high DC voltage signal is removed and the traveling wave signal is applied, the ions are forced into the exit transition section 158.

[0099] As previously mentioned, the exit transition section 158 tapers from the ion accumulation section 156 to the exit section 160. For example, the exit transition section 158 shown in FIG. 10 narrows from 31 rows to 11 rows. This taper allows ions to exit the accumulation section 156 and be transmitted to the exit section 160 while generally avoiding the ions reaching the space charge limit and being ejected due to space charge effects. In this regard, faster ions, e.g., ions having greater ion mobility, exit the accumulation section 156 more quickly than slower ions, causing the ions to separate as they traverse the exit transition section 158. Accordingly, a larger area is required immediately adjacent the gate electrode 166 to accommodate the accumulated charge of the released ions not yet separated at the beginning of the exit transition section 158 and prevent the ions from reaching the space charge limit. However, as the ions are separated, the accumulated charge of the released ions at a given location along the length of the exit transition section 158 is reduced, thus allowing the width of the exit transition section 158 to be gradually reduced to match the width of the exit section 160. Additionally, ions are held within the exit transition section 158 by a DC guard electrode 168 and prevented from exiting laterally, e.g., along the y-axis. It should be appreciated that the length of the exit transition section 158 and the slope of its taper can be adjusted depending on the number of charges stored in the ion accumulation section 156. For example, the exit transition section 158 shown in FIG. 10 has a length of 16 individual electrodes 122a-h, e.g., two groups of eight individual electrodes 122a-h, but could also be provided as eight individual electrodes 122a-h if that is determined to be sufficient. The exit section 160 receives the ions from the exit transition section 158 and transmits the ions to another section of the SLIM device 104.

[0100] 11 is a schematic diagram of the exemplary accumulation region 150 of FIG. 10 with a lateral inlet section 170 connected to the accumulation region 150. Specifically, in some embodiments of the present disclosure, the ion accumulation section 156 can have an opening on one or both lateral sides adjacent to the opening with the lateral inlet section 170 located. The lateral inlet section 170 can be substantially similar to the inlet section 152 and can include multiple rows of continuous electrodes 162 including multiple individual electrodes 122a-h and multiple segmented electrode arrays 164 (oriented vertically along the y-axis rather than horizontally along the z-axis as inlet section 152). The lateral inlet section 170 is configured to transmit ions directly into the ion accumulation section 156.

[0101] The ion accumulation section 156 may be utilized to accumulate ions and may function in accordance with the above description provided in connection with FIG. 10. In particular, the gate electrodes 166a, 166b may receive a high DC voltage signal from the controller 108 and may generate a high DC electric field (V / m) to trap ions within the accumulation section 156 when ions are provided to the accumulation section 156 by the lateral entrance section 170. In this regard, the ion accumulation section 156 may include two sets of gate electrodes 166a, 166b on either side of the ion accumulation section 156 and may provide a confinement zone between the two sets of gate electrodes 166a, 166b.

[0102] After a desired number of ions are accumulated in the accumulation section 156, the ions can be transmitted to either the exit section 160 or the entrance section 152, which can also function as the exit section, so long as appropriate traveling waves are applied to the entrance section 152 and the entrance transition section 154. In particular, when ions are sent to the exit section 160, the high DC voltage signal is removed from the right gate electrode 166b, and a traveling wave signal traveling in a positive direction along the z-axis is applied to individual electrodes 122a-h in the accumulation section 156 to push the ions into the exit transition section 158 and then to the exit section 160, where they can be provided to another pathway section of the SLIM device 104. Alternatively, if ions are to be sent to the entrance section 152, the high DC voltage signal is removed from the left gate electrode 166a, and a traveling wave signal traveling in a negative direction along the z-axis is applied to the individual electrodes 122a-h in the accumulation section 156, the entrance transition section 154 (functioning similarly to the exit transition section 158), and the entrance section 152 (functioning similarly to the exit section 160) to push the ions into the entrance transition section 154 and then into the entrance section 152 where they can be provided to another path section of the SLIM device 104. Accordingly, the ion accumulation section 156 is independently controllable and can be utilized to direct ions in different directions. Thus, the accumulation region 150 can be utilized not only to accumulate ions, but also as a directional switch. It should also be appreciated that the accumulation region 150 can be utilized as a directional switch that does not initially accumulate ions.

[0103] In addition, it should be understood that the transition sections 154, 158 can be substantially similarly configured and sized, e.g., have the same length and / or slope, or can be differently configured and / or shaped, as shown in Figure 11. For example, the design of the transition sections 154, 158 can be adjusted based on the particular implementation desired, followed by placement of the path sections of the SLIM device 104.

[0104] Other embodiments are within the scope and spirit of the disclosed subject matter. One or more examples of these embodiments are shown in the accompanying drawings. Those skilled in the art will appreciate that the systems, devices, and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments, and the scope of the disclosure is defined only by the claims. The configurations illustrated or described in connection with one exemplary embodiment may also be combined with the configurations of other embodiments. Such modifications and variations are intended to be included within the scope of the disclosure. Furthermore, in the present disclosure, similarly named components in the embodiments generally have similar configurations, and therefore are within the scope of certain embodiments in which each configuration of each such named component is not necessarily fully detailed.

[0105] The subject matter described herein can be implemented in digital electronic circuitry, or computer software, firmware, or hardware, or combinations thereof, including the structural means disclosed herein and structural equivalents thereof. The subject matter described herein can be implemented as one or more computer program products, such as one or more computer programs tangibly embodied in an information carrier (e.g., a machine-readable storage device), or in a propagating signal for execution by or control of the operation of a data processing apparatus (e.g., a programmable processor, a computer, or multiple computers). Computer programs (also known as programs, software, software applications, or code) can be written in any form of programming language, including compiled or interpreted languages, and can be implemented in any form including stand-alone programs or modules, components, subroutines, or other units suitable for use in a computing environment. A computer program does not necessarily correspond to a file. A program can be stored in a portion of a file that holds other programs or data, in a single file dedicated to the program, or in multiple linked files (e.g., files that store one or more modules, subprograms, or code portions). A computer program can be implemented to be executed on one computer or on multiple computers at one site, or can be implemented distributed across multiple sites and interconnected by a communications network.

[0106] The processes and logic flows described herein, including method steps of the subject matter described herein, may be performed by one or more programmable processors executing one or more computer programs to perform functions of the subject matter described herein by operating on input data to generate output. The processes and logic flows may also be performed by, and apparatus of the subject matter described herein may be implemented as, special purpose logic circuitry, such as an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0107] Processors suitable for executing computer programs include, by way of example, both general-purpose and special-purpose microprocessors, and any one or more processors of any kind of digital computer. In general, a processor can receive instructions and data from a read-only memory or a random access memory, or both. The basic elements of a computer are a processor for executing instructions, and one or more memory devices for storing instructions and data. In general, a computer can also include one or more mass storage devices, such as magnetic, magneto-optical, or optical disks, for storing data, or can be operatively linked to receive data from or transfer data to such storage devices, or both. Information carriers suitable for carrying computer program instructions and data include, by way of example, non-volatile memories, including semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices); magnetic disks (e.g., internal hard disks or removable disks); magneto-optical disks; and all forms of optical disks (e.g., CD and DVD disks). The processor and memory can be supplemented by, or incorporated in, special-purpose logic circuitry.

[0108] To provide for interaction with a user, the subject matter described herein can be implemented on a computer having a display device, such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user, as well as a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can be used to provide interaction with the user as well. For example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback), and input from the user can be received in any form, including acoustic, vocal, or tactile input.

[0109] The techniques described herein may be implemented using one or more modules. In this specification, the term "module" refers to computing software, firmware, hardware, and / or various combinations thereof. However, at least a module should not be interpreted as software that is not implemented on hardware, firmware, or recorded on a non-transitory processor-readable recordable storage medium (i.e., a module is not software itself). In fact, a "module" should always be interpreted to include at least some physical non-transitory hardware, such as a processor or part of a computer. Two different modules may share the same physical hardware (e.g., two different modules may use the same processor and network interface). The modules described herein may be integrated, integrated, separated, and / or replicated to accommodate different applications. Also, the functions described herein performed in a particular module may be performed in one or more other modules and / or by one or more other devices instead of or in addition to the functions performed in a particular module. Furthermore, the modules may be implemented across multiple devices and / or other components, local or remote from each other. Additionally, modules can be moved from one device and added to another device and / or included in both devices.

[0110] The subject matter described herein may be implemented within a computing system that includes back-end components (e.g., data servers), middleware components (e.g., application servers), or front-end components (e.g., client computers having a graphical user interface or web browser through which a user can interact with an implementation of the subject matter described herein), or any combination of such back-end, middleware, and front-end components. The components of the system may be interconnected by any form or medium of digital data communication, e.g., a communications network. Examples of communications networks include local area networks ("LANs") and wide area networks ("WANs"), e.g., the Internet.

[0111] Throughout the specification and claims, approximation language may be applied to modify quantitative expressions that may vary within acceptable limits without causing a change in the basic function to which they relate. Accordingly, values ​​modified by one or more terms such as "about" and "substantially" should not be limited to the exact value stated. In at least some cases, approximation language may correspond to the precision of an instrument for measuring the value. Throughout the specification and claims, range limits may be combined and / or substituted, and such ranges identify and include all subranges contained therein, unless the context or language indicates otherwise.

Claims

1. 1. An apparatus for ion accumulation comprising: a first region configured to receive ions and generate a first drive potential configured to guide the ions in a first direction across the first region; a second region adjacent to the first region and configured to receive ions from the first region and switch between a first state and a second state, the second region including a segmented electrode extending axially across the second region generating a first electric field when in the first state and a second electric field when in the second state; wherein the first electric field includes a second drive potential and a gate potential generated by segmented electrodes configured to accumulate ions in the second region and prevent ions from entering a third region adjacent the second region, and the second electric field includes a third drive potential generated by segmented electrodes configured to guide ions towards the third region; When the second region is in the first state, the first electric field prevents ions in the second region from leaving the second region and returning to the first region, causing ions to accumulate in the second region, and when the second region is in the second state, the second electric field moves ions toward the third region.

2. The apparatus of claim 1 , wherein the first electric field is generated at least in part by a DC voltage.

3. The apparatus of claim 2 , wherein the DC voltage magnitude is greater than the voltage bias of the first drive potential.

4. The apparatus of claim 2 , wherein the second electric field is a traveling wave.

5. The apparatus of claim 2 , wherein the magnitude of the DC voltage applied to some segments of the segmented electrode is less than the voltage bias of the second driving potential, thereby creating a potential well in the second region.

6. The third driving potential generated by the second electric field is a DC potential gradient or a traveling wave.

6. The apparatus of claim 5.

7. 3. The apparatus of claim 2, wherein the second driving potential of the first electric field is a traveling wave and the gate potential is a second traveling wave traveling in an opposite direction to the first traveling wave.

8. The apparatus of claim 1 , wherein the third region is configured to receive ions from the second region and generate a fourth driving potential configured to separate ions based on mobility.

9. the first region includes a plurality of electrodes disposed on the first surface and arranged along a first direction and configured to generate a first drive potential; 2. The apparatus of claim 1.

10. Controller includes: the controller is configured to apply a first voltage signal to a plurality of electrodes in a first region, the plurality of electrodes generating a first drive potential based on the first voltage signal; the controller is configured to apply a second voltage signal to at least one electrode segment of the segmented electrodes of the second region, the at least one electrode segment generating a gate potential based on the second voltage signal; the controller is configured to apply a third voltage signal to at least one electrode segment of the segmented electrodes of the second region, the at least one electrode segment generating a third drive potential based on the third voltage signal; When the device is in a first mode of operation, the controller applies a second voltage signal to at least one electrode segment of the segmented electrode to place the second region in a first state, and when the device is in a second mode of operation, the controller applies a third voltage signal to at least one electrode segment of the segmented electrode to place the second region in a second state.

10. The apparatus of claim 9.

11. 2. The device of claim 1 , wherein a first portion of the second region generates a first electric field when the second region is in a first state, the first portion of the second region generates a second electric field when the second region is in a second state, and the second portion of the second region generates a third electric field different from the first electric field.

12. 10. The device of claim 1, wherein the second region includes a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes.

13. The apparatus of claim 12 , wherein the first electric field is generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

14. 1. A method for ion accumulation comprising: introducing ions into a device for ion accumulation having a first region, a second region adjacent to the first region, and a third region adjacent to the second region; generating a driving potential in the first region to steer ions in a first direction across the first region; transmitting ions from the first region to the second region with a driving potential; generating a first electric field in the second region utilizing a segmented electrode extending axially across the second region while in a first state preventing ions from entering the third region, the first electric field including a second drive potential and a gate potential generated by the segmented electrode; accumulating ions in the second region using a gate potential; and switching the first electric field generated by the segmented electrodes in the second region to a second electric field to direct the accumulated ions in the first direction towards a third region.

15. The method of claim 14 , wherein at least a portion of the first electric field is generated by a DC voltage.

16. The method of claim 15 , wherein the magnitude of the DC voltage is greater than the voltage bias of the driving potential.

17. The method of claim 15 , wherein the second electric field is a traveling wave.

18. 16. The method of claim 15, wherein the magnitude of the DC voltage applied to some segments of the segmented electrode is less than the voltage bias of the second driving potential, thereby creating a potential well in the second region.

19. 20. The method of claim 18, wherein the second electric field is a DC potential gradient or a traveling wave.

20. 16. The method of claim 15, wherein the first electric field comprises a first traveling wave and the gate potential is a second traveling wave traveling in an opposite direction to the first traveling wave.

21. transmitting ions accumulated in the second region to a third region; generating a third drive potential in a third region; separating the ions based on their mobility using a second driving potential; The method of claim 14 further comprising:

22. the first region includes a plurality of electrodes disposed on the first surface and arranged along a first direction and configured to generate a first drive potential; The method of claim 14.

23. 15. The method of claim 14, wherein the second region includes a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes.

24. 24. The method of claim 23, wherein the first electric field is generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

25. 1. An ion storage device comprising: an ion storage section having a first width and configured to receive ions and switch between a first state and a second state to generate a first electric field using another axially transversely extending segmented electrode when in the first state and to generate a second electric field using the another segmented electrode when in the second state; an exit section having a second width less than the first width and configured to generate a third electric field configured to guide ions across the exit section; an exit transition section extending between the ion accumulation section and the exit section, the exit transition section having a tapered width decreasing from a first width adjacent the ion accumulation section to a second width adjacent the exit section, the exit transition section configured to generate a third electric field to guide ions across the exit transition section and into the exit section; wherein the first electric field is configured to accumulate ions in the ion accumulation section and prevent ions from moving in a first direction into the exit transition section, the first electric field comprising a drive potential and a gate potential; The second electric field is configured to guide ions in a first direction toward the exit transition section. R, When the ion accumulation section is in a first state, a first electric field prevents ions in the ion accumulation section from exiting the ion accumulation section and causes the ions to accumulate in the ion accumulation section, and when the ion accumulation section is in a second state, a second electric field moves the ions in a first direction toward the exit transition section.

26. an inlet section having a third width less than the first width; an inlet transition section extending between the entrance section and the ion accumulation section, the inlet transition section having a tapered width increasing from a third width adjacent the entrance section to a first width adjacent the ion accumulation section; wherein the entrance section and the entrance transition section are configured to generate a fourth electric field to guide ions across the entrance section and the entrance transition section to the ion accumulation section; 26. The ion storage device of claim 25.

27. 26. The ion storage device of claim 25, wherein the second electric field is a traveling wave traveling in a first direction, and the ion accumulation section is configured to switch from generating the second electric field to generate a fourth electric field, the fourth electric field being a traveling wave traveling in a second direction opposite the first direction.

28. The ion storage device of claim 25 , wherein the first electric field is generated at least in part by a DC voltage.

29. 26. The ion storage device of claim 25, wherein a first portion of the ion storage section generates a first electric field and a second portion of the ion storage section generates a fourth electric field different from the first electric field.

30. 26. The ion storage device of claim 25, wherein the ion accumulation section includes a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes.

31. The ion storage device of claim 30 , wherein the first electric field is generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays.

32. 26. The ion storage device of claim 25, comprising an inlet section located to a side of the ion storage section, the inlet section configured to provide ions to the ion storage section.

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