Ion guide assembly with multiple ion guides

Abstract

An ion guide assembly (2) comprising: two planar mounting components (4); and first and second ion guides (6, 8) mounted on the two planar mounting components such that the ion guides are spaced apart from one another, wherein at least one of the planar mounting components has an aperture (14) therethrough, the aperture being located on the at least one mounting component between the positions at which the first and second ion guides are mounted; and an ion optical device sized and configured to be inserted through the aperture in the planar mounting component and into the space between the first and second ion guides.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to UK Patent Application No. 2004014.3, filed on March 19, 2020. The entire contents of this application are incorporated herein by reference. Technical Field

[0003] The present invention generally relates to a mass spectrometer and / or an ion mobility spectrometer, and particularly to an ion guide assembly for guiding ions through such a spectrometer. Background Technology

[0004] The desired goal is to align multiple ion guides with each other and / or with other ion optics in a mass spectrometer or mobility spectrometer. However, it can be difficult to achieve and maintain ion guidance paths that align such components, especially when some ion optics need to be removed and replaced. Summary of the Invention

[0005] This invention provides an ion guide assembly, the ion guide assembly comprising:

[0006] Two flat-mounted components; and

[0007] First and second ion directors are mounted on two planar mounting components such that the ion directors are spaced apart from each other;

[0008] At least one of the planar mounting components has a through-hole located on the at least one mounting component between the positions where the first and second ion guides are mounted.

[0009] The aperture in at least one of the planar mounting components is sized and configured such that an ion optics device can be inserted through the aperture into the space between the first and second ion guides. The ion optics device is configured to receive ions from the first ion guide and transport the ions to the second ion guide.

[0010] The aperture can have a size in the dimension between the first and second ion guides selected from the group consisting of: > 5 mm; > 10 mm; > 15 mm; > 20 mm; < 30 mm; < 25 mm; < 20 mm; < 10 mm; or between 5 mm and 20 mm; and / or the aperture can have a size in the dimension orthogonal to the direction between the first and second ion guides selected from the group consisting of: > 5 mm; > 10 mm; > 15 mm; > 20 mm; > 25 mm; > 30 mm; < 40 mm; < 35 mm; < 30 mm; < 25 mm; < 20 mm; < 15 mm; between 5 and 30 mm; or between 10 and 25 mm. The aperture can have a combination of any one of the sizes listed for the dimension between the first and second ion guides with any one of the sizes listed for the orthogonal dimension.

[0011] The aperture can be rectangular, square or another shape such as oval.

[0012] The aperture can be completely surrounded by the material of the planar mounting component, that is to say not slotted from the outer edge of the planar mounting component.

[0013] The two planar mounting components can be arranged with their major faces facing each other and the first and second ion guides can be located between the two planar mounting components.

[0014] The planar mounting components can be rigid.

[0015] The planar mounting components can be arranged parallel to each other.

[0016] The first and / or second ion guides can be mounted directly to both of the mounting components.

[0017] The first and / or second ion guides comprise a plurality of electrodes arranged to define an elongate ion guiding path.

[0018] The first ion guide defines a first axis along which it guides ions and the second ion guide defines a second axis along which it guides ions, wherein the first and second axes can be coaxial.

[0019] The first and / or second ion guides can comprise a plurality of apertured electrodes spaced along the axial length of the ion guide, wherein the apertures in the electrodes are aligned so as to define a tunnel through which ions are guided in use.

[0020] The first and / or second ion guides can comprise a multi-pole ion guide such as a quadrupole rod set ion guide.

[0021] The ion guide assembly can include one or more voltage sources connected to the electrodes of each ion guide for applying voltages to those electrodes. For example, the ion guides can include an RF voltage source for applying an RF voltage to the electrodes of the first and / or second ion guides so as to radially confine ions to an ion guide path through the ion guides. In embodiments in which one or both of the ion guides is formed by axially spaced electrodes, such as a porous electrode or segmented multipole rod set, RF voltages of opposite phase can be applied to axially alternating electrodes so as to provide a radial confinement force on the ions.

[0022] The ion guide assembly can include one or more DC voltage sources for applying DC voltages to the electrodes of the first and / or second ion guides so as to axially propel ions along the ion guides. For example, the one or more DC voltage sources can be configured to successively apply a transient DC voltage to different electrodes or different groups of electrodes along the ion guides so as to propagate the transient DC voltage along the ion guides one or more times, thereby propelling ions along the ion guides.

[0023] Alternatively or additionally, the one or more DC voltage sources can be configured to simultaneously apply different DC voltages to different electrodes along the ion guides so as to generate an axial electric field along the ion guides.

[0024] One or both of the two mounting components can be a printed circuit board having electrical contacts thereon. The electrodes of the first and / or second ion guides can be electrically connected to the electrical contacts for applying voltages to the first and / or second ion guides via the PCB.

[0025] The PCB can be a component that contains electrical contacts in the form of conductive traces, pads, and other features etched, printed on, or deposited on one or more material sheets that are laminated to a non-conductive substrate.

[0026] The space between the two planar mounting components around at least the first ion guide can be sealed so as to define a first gas cell in which the first ion guide is located; and / or the space between the two planar mounting components around at least the second ion guide can be sealed so as to define a second gas cell in which the second ion guide is located.

[0027] Each of the first and / or second gas cells can be hermetic except for inlet and outlet apertures of the ion guide therein, e.g., such that these apertures act as differential pumping apertures between upstream and downstream regions. However, it is contemplated that one or more holes can be arranged to extend through the sealed portions or mounting components at one or more locations adjacent the ion guide so as to control gas flow or pressure within the ion guide.

[0028] The ion guide assembly can comprise at least one mounting fixture mounted to the planar mounting component for mounting the ion optical device to the mounting fixture.

[0029] The mounting components can each comprise a slotted aperture in which the mounting fixture is located.

[0030] Each slotted aperture can be sized and configured such that opposing side edges of the slotted aperture prevent movement of the mounting fixture in a first dimension (y-dimension).

[0031] The mounting fixture can have a surface that abuts a major surface of the planar mounting component. This can prevent movement of the mounting fixture in a second dimension (z-dimension).

[0032] The mounting fixture can comprise one or more protrusions that extend through one or more holes in one or both of the planar mounting components, respectively, and the one or more protrusions can be respectively limited by the one or more holes, thereby preventing movement of the mounting fixture. The protrusions and holes can cooperate to prevent movement of the mounting fixture in at least a third dimension (x-dimension).

[0033] The mounting fixture can comprise a screw, bolt, clamp, or other attachment mechanism for mounting the ion optical device to the mounting fixture.

[0034] The invention also provides a mass or mobility spectrometer comprising: an ion guide assembly as described herein; and a mass or mobility analyser downstream of the ion guide assembly.

[0035] The mass or mobility spectrometer can comprise an ion optical device sized and configured to be inserted through an aperture in the planar mounting component and into a space between the first and second ion guides.

[0036] The ion optical device can be mounted to the planar mounting component between the first and second ion guides.

[0037] The ion optical device can be mounted directly on the planar mounting component, or can be mounted to one or more of the mounting fixtures described herein.

[0038] The ion optical device can comprise a plurality of electrodes arranged to define an ion inlet and an ion outlet configured such that, when the ion optical device is arranged between the first and second ion guides, the ion optical device is able to receive ions from the first ion guide through the ion inlet and transmit the ions into the second ion guide through the ion outlet.

[0039] The ion optical device has a length of the aperture between its ion inlet and ion outlet in a dimension that is smaller than the length of the aperture between the first and second ion guides.

[0040] The ion optical device can have a height of the aperture in a dimension that is orthogonal to the direction between the first and second ion guides that is smaller than the height of the aperture between the first and second ion guides.

[0041] The ion optical device can comprise an ion guide having a form such as described in relation to the first and / or second ion guides, such as an ion tunnel ion guide, a multipole ion guide or an ion funnel ion guide.

[0042] The ion optical device can be a fragmentation device for fragmenting a precursor analyte ion to form a daughter ion, an activation device for activating an ion or a reaction device for reacting an analyte ion with other ions or non-ion molecules.

[0043] For example, the ion optical device can be a surface induced dissociation device (SID), an electron capture dissociation device (EDC), an electron impact dissociation device (EID) or a photo dissociation device.

[0044] The activation device described herein can be configured and operated to cause one or more of: de-clustering of the ions (i.e. to break up clusters of analyte ions and adduct species so as to separate the analyte ions from the adduct species); to apply energy to the ions so as to cause structural changes in the ions without fragmenting the ions (e.g. so as to change the conformation of the ions); and to apply energy to the ions by colliding the ions with background gas molecules so as to fragment the ions after they have been excited by another technique, such as having been exposed to electron capture or charge transfer conditions (e.g. ECD or ETD conditions). Thus, when the ion optical device is an activation device that fragments the ions after they have been excited, the spectrometer can also comprise an excitation device for performing such excitation on the ions before they are activated in the activation device. For example, the excitation device can be an electron capture dissociation device, an electron transfer dissociation device, an electron emitter or the like.

[0045] The spectrometer can comprise one or more vacuum chambers in which the ion guide assembly arrangement is disposed, and one or more vacuum pumps for evacuating the one or more vacuum chambers. The spectrometer can be configured to control the vacuum pump(s) so as to maintain the first and / or second ion guides at a pressure of at least 0.001 mbar.

[0046] The spectrometer can comprise one or more voltage sources configured to apply a voltage to the electrodes so as to cause ions to be accelerated into or within the first and / or second ion guides, so as to cause the ions to collide with background gas molecules and induce collision-induced dissociation or collision-induced activation.

[0047] To achieve this, the ions can be accelerated axially, for example by an axial potential difference. Alternatively, an AC voltage can be applied to the electrodes of the first and / or second ion guide so as to cause the ions to oscillate (e.g. in a radial or axial direction) so as to achieve collision-induced dissociation or collision-induced activation.

[0048] The spectrometer can comprise a pulsed ion source, a pulsed ion trap or an ion gate upstream of the ion guide assembly for transmitting a pulse of ions into the ion guide assembly.

[0049] Additionally or alternatively, a separation device can be provided upstream of the ion guide assembly for temporarily separating ions according to a physicochemical property, such as ion mobility or mass-to-charge ratio. For example, an ion mobility separator (IMS) can be provided upstream of the ion guide region so as to separate ions and transmit ions of different mobilities at different times into the ion guide assembly. Alternatively or additionally, a mass-selective ion trap or mass filter can be provided upstream of the ion guide region so as to transmit ions of different mass-to-charge ratios at different times into the ion guide assembly.

[0050] The spectrometer can comprise a closed-loop ion mobility separator.

[0051] The present disclosure also provides a method comprising: providing a mass or mobility spectrometer as described herein; and inserting an ion optical device through an aperture in the surface mount component and into the space between the first and second ion guides.

[0052] The ion optical device can then be mounted to the surface mount component, directly or indirectly (e.g. via a mounting fixture).

[0053] The method can further comprise removing the ion optical device from the space between the first and second ion guides through the aperture in the surface mount component.

[0054] The present disclosure also provides a method of mass or mobility spectrometry comprising: providing a mass or mobility spectrometer as described herein; guiding ions through the first ion guide, into the ion optical device, and then through the second ion guide; and performing mass or mobility analysis on the ions downstream of the second ion guide.

[0055] Although the ion guide assembly has been described as having two planar mounting components, it is contemplated that the first and second ion guides can instead be mounted on only a single planar mounting component, or on more than two planar mounting components.

[0056] Additionally or alternatively, it is contemplated that the one or more mounting components need not be planar.

[0057] The present application therefore also provides an ion guide assembly comprising: a mounting component; and first and second ion guides mounted on the mounting component such that the ion guides are spaced apart from one another; wherein the mounting component has an aperture therethrough, the aperture being located on the mounting component between the locations at which the first and second ion guides are mounted. BRIEF DESCRIPTION OF DRAWINGS

[0058] Various embodiments will now be described, by way of example only, and with reference to the accompanying drawings in which:

[0059] Figure 1 A schematic perspective view of an ion guide assembly according to an embodiment of the application is shown;

[0060] Figure 2 A cross-sectional view of a portion of the ion guide assembly shown in Figure 1 is shown; Figure 1

[0061] Figures 3 to 9 The positions of components in a spectrometer according to different embodiments of the application are shown. DETAILED DESCRIPTION

[0062] Figure 1 A schematic perspective view of an ion guide assembly 2 according to an embodiment of the application is shown, and Figure 2 A cross-sectional view of a portion of the same embodiment is shown.

[0063] ​The ion guide assembly 2 comprises two planar mounting components 4 arranged in parallel and having their major faces facing each other. A first ion guide 6 is arranged between and mounted directly to two of the mounting components 4. Similarly, a second ion guide 8 is arranged between and mounted directly to two of the mounting components 4. Each of the first and second ion guides 6, 8 comprises a plurality of electrodes 10 arranged to define an elongate ion guiding path. In the described embodiment, each of the first and second ion guides comprises a plurality of apertured electrodes 10 spaced along an axial length of the ion guide 6, 8, with the apertures in the electrodes 10 being aligned so as to define a tunnel through which ions are guided in use (i.e. the ion guides are ion tunnel ion guides or stacked ring ion guides). However, it is contemplated that one or both of the ion guides 6, 8 can be a different type of ion guide. For example, one or both of the ion guides can be a multipole ion guide, such as a quadrupole rod set ion guide.

[0064] A voltage source is connected to the electrodes 10 of each ion guide 6, 8 for applying voltages to the electrodes for the usual purposes in ion guides. For example, an RF voltage can be applied to the electrodes 10 of each ion guide 6, 8 so as to radially confine ions to the ion guiding path through the ion guide. In embodiments in which one or both of the ion guides 6, 8 is formed from axially spaced apertured electrodes 10, opposite phase RF voltages can be applied to axially alternating electrodes so as to provide a radial confinement force to ions. Alternatively or additionally, for example, a DC voltage can be applied to the electrodes 10 of one or both of the ion guides 6, 8 so as to axially push ions along one or both of the ion guides. For example, a transient DC voltage can be propagated along one or more times along the ion guide 6, 8 so as to push ions along the ion guide. Each time the transient DC voltage is propagated along the ion guide, the transient DC voltage can be applied continuously to different electrodes 10 along the ion guide, or to different groups of electrodes continuously so that the transient DC voltage moves along the ion guide. As the transient DC voltage creates a potential barrier, as the transient DC voltage moves along the ion guide 6, 8, the potential barrier pushes ions along the ion guide. Alternatively or additionally, instead of propagating a transient DC voltage along the ion guide, ions can be pushed along the ion guide by simultaneously applying different DC voltages to different electrodes of the ion guide so as to generate an axial electric field along the ion guide.

[0065] It is contemplated that one or both of the mounting components 4 can be a printed circuit board (PCB), and the electrodes 10 of the ion guides 6, 8 can be electrically connected to electrical contacts 12 on the PCB(s) so that voltages can be supplied to the electrodes 10 of the ion guides 6, 8 via the PCBs. This provides mounting components 4 that both maintain the mechanical alignment of the two ion guides 6, 8 and also make it easy to apply voltages to their electrodes 10.

[0066] The first ion guide 6 and the second ion guide 8 are spaced apart from one another. The downstream end of the first ion guide 6 is spaced apart from the upstream end of the second ion guide 8 along a direction corresponding to the ion guide axis through the first ion guide 6. As will be described further below, this allows an ion optical device to be inserted into the space between the ion guides 6, 8 in order to receive ions from the first ion guide 6 and transmit the ions into the second ion guide 8. The ion guide axis through the first ion guide 6 can be substantially parallel to the ion guide axis through the second ion guide 8. The ion guide axis through the first ion guide 6 can be coaxial with the ion guide axis through the second ion guide 8, although it is contemplated that the ion guide axes of the ion guides 6, 8 can not be coaxial and can be offset from one another, for example, in a radial direction of the ion guides 6, 8.

[0067] At the part of the planar mounting member 4 between the parts at which the first ion guide 6 and the second ion guide 8 are mounted, an aperture 14 is provided through one or both of the planar mounting members 4. The aperture 14 is positioned so as to allow an ion optical device to be inserted through the aperture 14 in the mounting member 4 and into the space between the ion guide 6, ion guide 8, so that the ion optical device is aligned with the first ion guide 6 and the second ion guide 8. This enables ions guided through the first ion guide 6 to pass into the ion optical device, and enables ions exiting the ion optical device to pass into the second ion guide 8, so as to be guided downstream thereby. For example, the ion optical device can be a fragmentation device for fragmenting precursor analyte ions to form daughter ions, for example the ion optical device can be a surface induced dissociation device (SID), an electron capture dissociation device (ECD), an electron impact dissociation device (EID) or a photo-dissociation device such as an ultraviolet photo-dissociation (UVPD) device or an infrared photo-dissociation (IRPD) device. Alternatively, the ion optical device can be an activation device (for example for activating ion clusters so as to break them down into analyte ions and adduct species), or a reaction device for reacting analyte ions with other ions or non-ionic molecules (for example to fragment the analyte ions or to transfer charge to them).

[0068] Once the ion optical device is inserted through one of the apertures 14 in one of the mounting members 4, it can be mounted directly to both mounting members 4, for example via screws, bolts, clamps, welding or soldering (not shown). Alternatively, as shown in Figures 1 1 and 12, a mounting fixture 16 can be mounted to the mounting members 4, and the ion optical device can be mounted to the mounting fixture 16. Figure 1 and 2

[0069] ​In the depicted embodiment, the apertures 14 in the mounting components 4 are of the same shape and size, and are in coincident positions, although this need not be the case. Each aperture 14 includes a relatively large main portion for insertion of an ion optical component therethrough, and also a slotted portion 18 at its upper end for receiving a mounting fixture 16 extending between two mounting components 4. Each slotted portion 18 receives a mounting fixture 16, and is sized and configured such that opposite side edges of the slotted portion 18 prevent movement of the mounting fixture in a first dimension (the y dimension). The mounting fixture 16 can also be configured such that when it is disposed in the slotted portion 18, outwardly facing surfaces (in the z dimension) of the mounting fixture 16 abut inwardly facing major surfaces of the mounting components 4, so as to prevent movement of the mounting fixture 16 in a second dimension (the z dimension). Each of these outwardly facing surfaces of the mounting fixture 16 can also include a protrusion 20 that extends through a hole in each of the mounting components 4 that is spaced apart from the aperture 14, thereby preventing movement of the mounting fixture 16 in at least a third dimension (the x dimension). The mounting fixture 16 can include screws 22 or other attachment means, such as bolts or clamps, for mounting an ion optical device thereto. Alternatively, the ion optical device can be welded or brazed to the mounting fixture 16.

[0070] Each aperture 14 in the mounting components 4 can also include a second slotted portion 18 at its lower end for receiving a second mounting fixture 16 extending between two mounting components 4. The second slotted portion 18 and second mounting fixture 16 can be configured in a manner corresponding to that described above, and an ion optical device can also be mounted to the second mounting fixture in a manner corresponding to that described above. Although the slotted portions 18 have been described as being in upper and lower portions of the mounting components 4 in the y dimension, the y dimension can not be vertical, and can be in any orientation.

[0071] In use, ions from an ion source are introduced into the first ion guide 6 of the ion guide assembly 2. The ions are then passed from the first ion guide 6 into an ion optical device (e.g. a dissociation or activation device) that has been mounted to the mounting components 4 of the ion guide assembly 2. The ions are processed within the ion optical device, for example by being dissociated or fragmented. The resulting ions are then passed into the second ion guide 8 of the ion guide assembly 2, and are transported downstream by it to a mass or mobility analyzer in which the ions are mass or mobility analyzed.

[0072] It is contemplated that the ion guide assembly 2 can be arranged within a mass spectrometer or mobility spectrometer such that the first ion guide 6 and / or the second ion guide 8 and / or the ion optical devices are held at a desired pressure(s). For example, any one or more of these devices can be held at a relatively low pressure such that ions transmitted therethrough have a relatively low or substantially no collision with background gas molecules. Alternatively or additionally (i.e., for different devices), any one or more of these devices can be held at a relatively high pressure such that ions transmitted therethrough have a relatively high collision rate with background gas molecules. The pressure at which various devices are held can be controlled by arranging the various devices on one or more chambers and using one or more vacuum pumps to reduce the pressure in the one or more chambers below atmospheric pressure.

[0073] The ion guide assembly can also be designed to control the pressure and / or gas flow within the ion path therethrough. For example, the space between the mounting components 4 around the first ion guide 6 can be sealed so as to define a gas cell in which the first ion guide 6 is located. The gas cell can be hermetically sealed except for inlet and outlet orifices of the first ion guide 6, for example, such that these orifices act as differential pumping apertures between upstream and downstream regions. However, it is contemplated that one or more holes can be arranged to extend through the sealed portion or mounting components 4 at one or more locations adjacent the first ion guide 6 so as to control the gas flow or pressure within the first ion guide 6. For example, gas can be introduced into or extracted from the first ion guide 6 through such holes. Alternatively or additionally, the second ion guide 8 can be sealed in a manner corresponding to the above-described manner.

[0074] The first ion guide 6 and / or the second ion guide 8 and / or the ion optical device can be maintained at a relatively high pressure, for example at about 0.001 mbar or more. The background gas maintained at this pressure can be an inert gas, for example nitrogen. At such a relatively high pressure, ions passing through the first ion guide 6 and / or the second ion guide 8 (and / or the ion optical device) are moderated by collisions with background gas molecules, which improves ion trapping and transmission to the immediately downstream device (and possibly one or more devices further downstream). At these pressure regimes, RF voltages can be applied to the electrodes 10 of the first ion guide 6 and / or the second ion guide 8 and / or the ion optical device in order to radially confine ions therein, as described above. Embodiments are contemplated in which collision-induced dissociation (CID) or collision-induced activation is performed in the first ion guide 6 and / or the second ion guide 8 and / or the ion optical device maintained at such a relatively high pressure. For example, voltages can be applied to the instrument such that ions are accelerated into or within one or more of these devices, so that the ions collide with background gas molecules and CID or collision-induced activation is induced. To achieve this, ions can be accelerated axially, for example by an axial potential difference. Alternatively, AC voltages can be applied to the electrodes of one or more of the devices in order to oscillate ions (for example, in the radial or axial direction) in order to achieve CID or collision-induced activation.

[0075] It is also contemplated that the first ion guide 6 and / or the second ion guide 8 and / or the ion optical device can be maintained at a relatively low pressure, for example such that there are relatively few or substantially no collisions between ions and background gas molecules. At such pressures, RF confinement of ions is still desirable, although it can not be required if the device is relatively short such that ion collisions with background gas molecules are minimised.

[0076] For ions having desired physicochemical properties, the ion guide assembly 2 can be disposed downstream of an apparatus that provides a relatively short time profile (e.g., < 100 milliseconds). The relatively short time profile can be provided by a range of techniques, such as but not limited to providing ions from a pulsed ion source, providing ions into the ion guide assembly 2 from an ion accumulation region such as an ion trap, or by gating the transmission of ions into the ion guide assembly 2 using ion gates. Additionally or alternatively, the relatively short time profile can be provided using a separation device that provides ions separated in time according to a physicochemical property such as but not limited to ion mobility or mass-to-charge ratio. For example, an ion mobility separator (IMS) can be used to separate ions and transmit them into the ion guide assembly. Alternatively, a mass-to-charge separator can be used to separate ions and transmit them into the ion guide assembly, for example, by selectively ejecting ions of different mass-to-charge ratios from an ion trap at different times and into the ion guide assembly, or by transmitting ions through a mass filter such as a quadrupole mass filter having a mass transmission window that is scanned or stepped in time.

[0077] In embodiments in which ions having a relatively short time profile are provided, it can be desirable to control the transit times of ions through the first ion guide 6 and / or the second ion guide 8 and / or the ion optical device (and optionally further downstream regions) in order to preserve the fidelity of the time-separated ions. This can be achieved by applying an axial electric field to the first ion guide 6 and / or the second ion guide 8 and / or the ion optical device, or by propagating a transient DC voltage along it in order to push the ions along the axis. As described above in relation to the first ion guide 6 and the second ion guide 8, this can be achieved by providing axially spaced electrodes for each device and applying DC voltages to these electrodes to form an axial electric field or to propagate a transient DC voltage. Dedicated electrodes can be provided for generating the axial electric field or propagating the transient DC voltage. Alternatively, these DC voltages can be provided to electrodes of the device that perform other functions, for example RF trapping electrodes. Less preferably, the transit of ions through the device can be controlled by varying the gas flow through the device. Although embodiments have been described in which ions are provided to the ion guide assembly 2 having a relatively short time profile, it is contemplated that this need not be the case.

[0078] The ion guide assembly 2 described herein can be incorporated into a variety of different instrument geometries, some of which are shown in Figures 3 to 9 Generally speaking, one or more of the following devices can be arranged upstream and / or downstream of the ion guide assembly 2: an ion source, a mass analyser, a mass separator, a mass filter, an ion mobility-based analyser, an ion mobility-based separator, an ion mobility filter, and a fragmentation device.

[0079] Figure 3 An embodiment is shown in which an ion guide assembly 2 is arranged between an ion source 30 and a mass analyser 32. An ion optical device 31 is arranged within the ion guide assembly. In use, ions from the ion source 30 are introduced into the first ion guide 6 of the ion guide assembly 2. The ions are then passed from the first ion guide 6 into the ion optical device 31 (e.g. a dissociation or activation device) which has been mounted to a mounting component of the ion guide assembly. The ions are processed within the ion optical device 31, for example by being dissociated or fragmented. The resulting ions are then passed into the second ion guide 8 of the ion guide assembly 2 and transmitted downstream by it to the mass analyser 32 where the ions are mass analysed.

[0080] Figure 4 An embodiment is shown which is identical to the embodiment of Figure 3 except that a mass filter 34, such as a resolving quadrupole mass filter (i.e. with RF and DC voltages) is arranged between the ion source 30 and the ion guide assembly 2. The mass filter 34 can be operated so as to have a mass transmission window such that it selectively transmits only ions of a particular mass to charge ratio to the ion guide assembly 2. The voltages applied to the electrodes of the mass filter 34 can be varied over time such that the mass filter transmits ions of different mass to charge ratios at different times, for example by substantially continuously scanning or stepping the mass to charge ratio being transmitted. It is also contemplated that in another mode the mass filter 34 can be operated as an ion guide which transmits all ions (e.g. an ion guide with only RF).

[0081] Figure 5 An embodiment is shown which is identical to the embodiment of Figure 4 except that an ion mobility separator (IMS) 36 is arranged between the mass filter 34 and the ion guide assembly 2. Ions transmitted by the mass filter 34 can be separated in the IMS device 36 such that ions of different mobilities reach the ion guide assembly 2 at different times. The IMS device 36 can be a drift IMS device in which ions are pushed through a gas towards an outlet of the device by a static voltage gradient or by a propagating transient DC voltage along the IMS device such that ions of different mobilities have different transit times through the IMS device. Alternatively, the IMS device can be a FAIMS device which is operated such that ions of different FAIMS mobilities leave at different times. The mass filter 34 can be operated as described in relation to Figure 4 and the ions transmitted thereby can be separated in the downstream IMS device 36. For example, the IMS can be operated in synchronisation with the mass filter such that the combination of the two devices transmits ions of a selected charge state.

[0082] Figure 6 An embodiment is shown which is identical to that of Figure 5 except that the order of mass filter 34 and IMS device 36 is reversed.

[0083] Figure 7 An embodiment is shown which is identical to that of Figure 5 except that IMS device 36 is a quadrupole IMS device or a closed loop IMS device, for example such as disclosed in WO 2015 / 155551. Ion trap 38 can be arranged upstream of IMS device 36 for trapping and releasing ions towards the IMS device.

[0084] Figure 8 An embodiment is shown which is identical to that of Figure 7 except that the position of ion guide assembly 2 is between ion trap 38 and IMS device 36.

[0085] Figure 9 An embodiment is shown which is identical to that of Figure 7 except that the position of ion guide assembly 2 is between mass filter 34 and ion trap 38.

[0086] In embodiments described herein, the mass analyser at the downstream end of the instrument is preferably a Time of Flight (ToF) mass analyser, a quadrupole mass analyser, a Fourier transform mass analyser or an ion trap mass analyser.

[0087] While the application has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes can be made and

[0088] For example, the present disclosure has been described in the context of upstream and downstream directions, however, the direction of ion motion through the instrument can be reversed so as to pass ions back and forth along the ion guide. For example, precursor ions can be passed through the instrument in the downstream direction and split in the ion optical device. The split ions can then be passed back upstream before being transmitted in the downstream direction for analysis.

Claims

1. An ion guide assembly comprising: Two flat-mounted components; First and second ion directors are mounted on the two planar mounting members such that the ion directors are spaced apart from each other, wherein at least one of the planar mounting members has a through-hole located on the at least one mounting member between the positions where the first and second ion directors are mounted. as well as An ion optics device, the ion optics device being sized and configured to be inserted through the aperture in the planar mounting member and into the space between the first and second ion guides.

2. The ion guide assembly of claim 1, wherein the pore has a size of ≥5 mm in the dimension between the first and second ion guides; and / or The pores have a size of ≥5 mm in a dimension orthogonal to the direction between the first and second ion guides.

3. The ion guide assembly of claim 1, wherein the two planar mounting members are arranged such that their main faces face each other, and wherein the first and second ion guides are located between the two planar mounting members.

4. The ion guide assembly of claim 1, wherein the first ion guide defines a first axis along which the first ion guide guides ions, and the second ion guide defines a second axis along which the second ion guide guides ions, wherein the first and second axes are coaxial.

5. The ion guide assembly of claim 1, wherein one or both of the two planar mounting components are printed circuit boards having electrical contacts thereon, and wherein the electrodes of the first and / or second ion guides are electrically connected to the electrical contacts for applying voltage to the first and / or second ion guides via the printed circuit board.

6. The ion guide assembly of claim 1, wherein the space between the two planar mounting members and around the first ion guide is sealed to define a first gas pool in which the first ion guide is located; and / or The space between the two planar mounting components and around the second ion guide is sealed to define a second gas pool in which the second ion guide is located.

7. The ion guide assembly of claim 1, comprising at least one mounting member, said at least one mounting member being mounted to the planar mounting component for mounting the ion optics device to the mounting member.

8. The ion guide assembly of claim 7, wherein each of the planar mounting components includes a slotted opening therein where the mounting fastener is located.

9. The ion guide assembly of claim 7, wherein the mounting member has a surface abutting against the main surface of the planar mounting member.

10. The ion guide assembly of claim 7, wherein the mounting member includes one or more protrusions extending through holes in one or both of the planar mounting members, and wherein the one or more protrusions are respectively limited by the holes in one or both of the planar mounting members to prevent movement of the mounting member.

11. The ion guide assembly of claim 7, wherein the mounting fastener includes screws, bolts, clamps or other attachment mechanisms for mounting the ion optics device to the mounting fastener.

12. The ion guide assembly of claim 1, wherein the ion optics are mounted to the planar mounting member between the first and second ion guides.

13. The ion guide assembly of claim 1, wherein the ion optics includes a plurality of electrodes arranged to define an ion inlet and an ion outlet, the ion inlet and the ion outlet being configured such that when the ion optics is arranged between the first and second ion guides, the ion optics can receive ions from the first ion guide through the ion inlet and transfer ions to the second ion guide through the ion outlet.

14. The ion guide assembly of claim 1, wherein the ion optics device is a splitting device for splitting precursor analyte ions to form daughter ions, an activation device for activating ions, or a reaction device for causing analyte ions to react with other ions or non-ionic molecules.

15. A mass spectrometer or mobility spectrometer, comprising: The ion guide assembly according to any one of claims 1 to 14; as well as The mass or mobility analyzer downstream of the ion guide assembly.

16. The spectrometer of claim 15, comprising one or more vacuum chambers in which the ion guide assembly is disposed, and one or more vacuum pumps for evacuating the one or more vacuum chambers, wherein the spectrometer is configured to control the vacuum pumps to maintain the first and / or second ion guide at a pressure of at least 0.001 mbar.

17. The spectrometer according to claim 15 or 16, comprising a closed-loop ion migration separator.

18. A method for mass spectrometry or mobility spectrometry, comprising: Provide an ion guide assembly according to any one of claims 1 to 14 or a mass spectrometer or mobility spectrometer according to any one of claims 15 to 17; as well as The ion optics device is inserted through the aperture in the planar mounting component and into the space between the first and second ion guides.

19. A method for mass spectrometry or mobility spectrometry, comprising: Provide a mass spectrometer or mobility spectrometer according to any one of claims 15 to 17; Ions are guided through the first ion guide, into the ion optics device, and then through the second ion guide; and Mass or mobility analysis is performed on the ions downstream of the second ion guide.

20. An ion guide assembly comprising: Mounting components; First and second ion directors are mounted on the mounting member such that the ion directors are spaced apart from each other, wherein the mounting member has through-holes located on the mounting member between positions where the first and second ion directors are mounted; as well as An ion optical device, the ion optical device being sized and configured to be inserted through the aperture in the mounting member and into the space between the first and second ion guides.

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