Cleaning of ion-optical multipole devices

Abstract

Cleaning device (1) for cleaning several elongated electrodes (100) of an ion-optical multipole device, wherein the cleaning device (1) comprises at least one substantially longitudinal cleaning section (20), at least one handling section (30) extending axially from the at least one cleaning section (20), and at least one directional section (50) extending axially from the at least one cleaning section (20), characterized in that the cleaning section (20) comprises a series of cleaning elements projecting from a body (10), wherein the directional section (50) comprises at least one flexible element projecting from the body (10) and at least one blocking element (52) arranged next to the flexible element to block any bending of the flexible element in the direction of the blocking element (52).wherein the at least one cleaning section (20) has a larger cross-section than the at least one handling section (30) and the at least one directional section (50) can allow a longitudinal movement of the cleaning device (1) in a first axial direction and resist a longitudinal movement of the cleaning device (1) in a second, opposite axial direction.

Description

Field of the invention

[0001] The present invention relates to an apparatus and method for cleaning ion-optical multipole devices. More particularly, the present invention relates to an apparatus for cleaning electrodes of ion-optical multipole devices, such as quadrupole devices, without disassembling the multipole device or even removing a housing of the multipole device. Background of the invention

[0002] Many types of mass spectrometers include at least one ion-optical multipole device for guiding and filtering ions. Typically, such a multipole device is a quadrupole device with four parallel, elongated electrodes arranged symmetrically around a central axis. Other multipole devices are also known, for example, hexapole devices and octopole devices with six and eight parallel, elongated electrodes, respectively. The surfaces of the parallel electrodes define an interior space or an internal channel through which ions can be guided.

[0003] The DC and AC voltages applied to the electrodes of a multipole device induce electric fields that allow ions with a specific m / z (mass-to-charge) ratio to pass through the multipole device while blocking other ions, thus forming a so-called mass filter. The blocked ions can impinge on the electrodes and gradually form deposits on them. In transport multipoles or ion traps, deposits can also be caused by the limited acceptance or radial ejection of ions. This means that deposits can build up in the entrance or exit region of the multipole device, including all exit slots. Clearly, such deposits negatively impact the proper functioning of the multipole device. It is therefore necessary to clean a multipole device regularly.

[0004] It is known to disassemble a multipole device and clean the electrodes individually, for example, by immersing them in a liquid and rubbing them with a brush or other cleaning tool. Laser cleaning has also been proposed. However, these methods have the disadvantage that the electrodes of the multipole device must be realigned after assembly to ensure proper functioning of the device. This realignment must be performed by a skilled technician and cannot be performed by a typical mass spectrometer user. Immersing the electrodes in a liquid has the additional disadvantage that it is difficult to remove the liquid from any holes in the electrodes. Furthermore, reassembling a multipole device can result in mechanical damage to the electrodes.

[0005] DE 10 2009 011 204 A1 relates to a device and a method for cleaning channels of medical instruments, which is constructed from a rod-shaped support element and at least one cleaning element connected to the support element and has at least one additional cleaning element that can be detached from the support element. DE 20 2016 005 151 U1 relates to a device for cleaning a narrow, long channel of a medical instrument with a flexible body that can be inserted into an instrument channel, wherein the device comprises at least one cleaning element with the function of a wiper and at least one cleaning element with the function of a brush.

[0006] It is therefore desirable to be able to clean a multipole device, such as an ion-optical multipole device, without disassembling it and without immersing it in a liquid. Brief description of the invention

[0007] To solve these problems of the prior art, the present invention provides a cleaning device for cleaning a plurality of elongated electrodes of an ion-optical multipole device, such as a multipole device of a mass spectrometer, the cleaning device comprising at least one substantially longitudinal cleaning section and at least one handling section extending axially from the at least one cleaning section, the at least one cleaning section having a larger cross-section than the at least one handling section.

[0008] By providing a cleaning device having a substantially longitudinal cleaning portion with an axially extending handling portion, it is possible to insert the cleaning device into the space between the electrodes of a multipole device and clean the electrodes without disassembling the multipole device. That is, to be suitable for cleaning the electrodes, the cleaning device is arranged so that it can be inserted between the electrodes, and the longitudinal construction of the cleaning device facilitates insertion. This eliminates the need to disassemble the multipole device and realign the electrodes after assembly.

[0009] The at least one cleaning section has a larger cross-section than the at least one handling section, so that contact between the cleaning device and the electrodes of the multipole device occurs primarily or exclusively at the cleaning sections. This ensures that contact between the device and the electrodes occurs only in the desired areas of the device, i.e., the cleaning areas, while avoiding unnecessary friction between the handling section (or sections) and the electrodes.

[0010] The device according to the invention further comprises at least one directional section extending axially from the at least one cleaning section. The at least one directional section can enable longitudinal movement of the device in a first axial direction and resist longitudinal movement of the device in a second, opposite axial direction. Such a directional section is designed to provide the device with a preferred insertion direction by generating less friction in one direction than in the opposite direction. This, in turn, causes the device to be moved in only one direction by a multipole device, thereby moving removed deposits out of the multipole device in a single direction.

[0011] The cleaning sections may have a shape suitable for contacting and cleaning the surfaces of the electrodes. For example, at least one cleaning section may have a substantially polygonal cross-sectional shape, such as square, hexagonal, or octagonal. Alternatively or additionally, at least one cleaning section may have a substantially circular cross-sectional shape or a substantially elliptical cross-sectional shape. The actual shape selected may also depend on the number of electrodes of the multipole device (e.g., quadrupole, hexapole, or octopole) and / or their orientation relative to one another.

[0012] In embodiments in which the cleaning device comprises at least two cleaning sections, two cleaning sections can have different cross-sectional shapes and / or different cross-sectional dimensions. This means that not all cleaning sections need to have the same cross-sectional shape and / or the same cross-sectional dimensions. The shape and / or dimensions of a cleaning section can depend, for example, on whether a cleaning fluid is applied to the specific cleaning sections and which cleaning fluid is applied. However, in embodiments in which the device comprises at least two cleaning sections, it is also possible for two cleaning sections to have identical cross-sectional shapes and / or cross-sectional dimensions.It is understood that in embodiments in which the device comprises three cleaning sections, two cleaning sections may have identical cross-sectional dimensions and / or shapes, while one cleaning section has different cross-sectional dimensions and / or a different shape.

[0013] In advantageous embodiments, the device comprises two or more cleaning sections separated by at least one spacer section, wherein the at least one spacer section has a smaller cross-section than the cleaning sections. A spacer section serves to keep the cleaning sections, and thus all cleaning fluids applied to these cleaning sections, spaced apart from one another.

[0014] According to the invention, at least one cleaning section comprises a series of cleaning elements protruding from a body, preferably a longitudinal body, such as a shaft. That is, in such an embodiment, a cleaning section comprises a number of substantially separate cleaning elements. In other embodiments, however, a cleaning section may consist of a single element, for example, a substantially tubular element made of leather or another suitable material.

[0015] In an embodiment in which at least one cleaning section comprises a series of cleaning elements protruding from the body, the cleaning elements may comprise cleaning flanges. Such cleaning flanges may, for example, consist of disc-shaped elements. At least some cleaning flanges may protrude substantially perpendicularly from the body. However, in some embodiments, at least some cleaning flanges protrude from the body at an acute angle, so that the cleaning flanges have an inclination in a specific direction, which is preferably opposite to the direction in which the device is inserted into the multipole device, so as not to cause excessive friction.

[0016] At least some of the cleaning flanges may be substantially flat, so that the cleaning flanges may, for example, consist of flat discs. However, at least some of the cleaning flanges may be curved. Curved cleaning flanges may be convex or concave. A specific curvature may be chosen to increase or decrease the area of ​​the cleaning flanges that contacts the electrodes.

[0017] In a suitable embodiment, at least one cleaning section is arranged so that it is compressible. Compressible cleaning sections allow the device to be easily used in various multipole devices with different dimensions, particularly in multipole devices where the cross-sections of the internal channel or space defined by the parallel elongated electrodes differ. Furthermore, if the compressible cleaning sections are elastic, the pressure with which the cleaning sections contact the surfaces of the electrodes is increased, resulting in an improved cleaning effect.

[0018] At least one cleaning section can absorb and release a cleaning fluid. In this way, a cleaning fluid can be absorbed by a cleaning section before the device is inserted into the multipole device, and the cleaning fluid can be released again after insertion, for example, if the cleaning section that has absorbed the fluid is compressible. Such a mechanism allows the device to be used to deliver cleaning fluid into the multipole device.

[0019] The cleaning sections can be made of different materials depending on their specific shape, structure, and purpose. In certain embodiments, at least one cleaning section comprises cellulose. For example, if a cleaning section comprises cleaning discs, these cleaning discs can advantageously be made of cellulose. It is understood that different cleaning sections can be made of different materials, and that even two or more different materials can be used in a single cleaning section. Other materials that can advantageously be used include, for example, natural or synthetic leather or various plastics.

[0020] In a particularly advantageous embodiment, the device comprises three cleaning sections separated by spacer sections. The spacer sections may have a smaller diameter than the cleaning sections and, for example, a length in the range of a few millimeters to a few centimeters. A device with three consecutive cleaning sections is particularly suitable for applying a first cleaning liquid, such as water, using the first cleaning section to be introduced, applying a second cleaning liquid, such as an organic or other solvent, to remove the water using the second cleaning section, and drying using the third cleaning section. The deposits on the electrodes are largely water-soluble. In embodiments, an additive, such as soap, can be added to the water.A suitable solvent is isopropanol, although the invention is not limited to this specific solvent. The solvent is used primarily to remove the water. In some embodiments, pure or substantially pure water is used. In other embodiments, mixtures of water and a solvent are used instead of or in addition to pure water. For example, a mixture of 70% water and 30% solvent (such as isopropanol) can be applied to the first cleaning section, and a mixture of 30% water and 70% solvent can be applied to the second cleaning section.Of course, other ratios can also be used, for example 80% water and 20% solvent in the first cleaning section and 20% water and 80% solvent in the second cleaning section, or 90% and 10% combined with 20% and 80%, since the ratios of water and solvent do not have to be reversed.

[0021] It is understood that sequences other than the sequence of applying water, applying solvent, and drying are also possible, and that embodiments of the device can be provided that have more than three cleaning sections, such as four, five, six, seven, eight, nine, or ten cleaning sections. In such embodiments, two or more different solvents, and / or water with and without additives, and / or solvent, and / or water and solvent in different mixing ratios, and / or more than one dry cleaning section could be used. As mentioned above, embodiments with two cleaning sections or only a single cleaning section are also possible.

[0022] According to the invention, the directional section comprises at least one flexible element protruding from the body and at least one blocking element arranged adjacent to the flexible element to block any bending of the flexible element in the direction of the blocking element. The blocking element prevents bending of the flexible element in one direction but allows bending of the flexible element in the other direction. The flexible element may comprise a flange whose cross-section is larger than that of the blocking element.

[0023] The cleaning device according to the invention can have a single handling section at one end of the cleaning device or two handling sections at each end of the device. At least one of the handling sections can be significantly longer than the combined cleaning sections, for example, at least twice as long. Preferably, at least one handling section should be at least as long as the electrodes to be cleaned. This enables easy handling of the cleaning device. It is noted that in some embodiments, the combined cleaning sections can be at least as long as the electrodes to be cleaned. In such embodiments, the handling sections can be relatively shorter.

[0024] The at least one handling portion may be substantially rigid or substantially flexible. In one embodiment, the handling portion comprises a substantially rigid rod, which may also be referred to as a handle. This allows the handling portion or handle to be easily pushed through the multipole device until it appears at the opposite end of the assembly, from where it can be pulled. However, in some embodiments, the handling portion may comprise a substantially flexible element, such as a cord or rope, which can be passed through the internal channel between the electrodes, for example, using an additional tool.

[0025] In one embodiment, the device comprises two handling sections, wherein a handling section at one end of the cleaning sections is at least five times as long as the other handle section at the opposite end of the one or more cleaning sections, preferably at least ten times as long. This facilitates insertion into and removal from a multipole device. As mentioned above, at least one handling section should preferably have a length that is at least equal to the length of the electrodes to be cleaned or at least equal to the length of the multipole device to be cleaned. This ensures that a handling section inserted into a multipole device at one end exits from the other end after being passed through, so that it can be pulled out at the other end.The person skilled in the art who wishes to clean a particular multi-pole device can easily determine a suitable length of the device according to the invention.

[0026] Similarly, at least one cleaning section should preferably have a cross-section that exceeds the inscribed diameter of the multipole device electrodes to be cleaned. That is, the cross-sectional dimensions of the at least one cleaning section are selected such that the cross-sectional dimensions are larger than the cross-sectional dimensions of the internal channel between the electrodes of the multipole device, this cross-sectional dimension typically being referred to as the inscribed diameter. If the cross-section of at least one cleaning section exceeds the inscribed diameter, even if only by a few percent, good contact between the cleaning section and the surfaces of the electrodes is achieved. The at least one cleaning section should exceed the inscribed diameter by 1% to 50%, for example 3% to 30%, preferably 5% to 20%, more preferably 5% to 10%.The person skilled in the art who wishes to clean a particular multi-pole device can easily determine a suitable diameter of the device according to the invention.

[0027] The invention additionally provides a method for cleaning electrodes of a mass spectrometer, the method comprising the use of an apparatus as described above.

[0028] In some embodiments, the method further comprises using at least two different cleaning liquids to be applied to at least two respective cleaning sections of the device. That is, a different cleaning liquid can be applied to each cleaning section. In some embodiments, at least one cleaning liquid is water, while at least one cleaning liquid can be a solvent. The solvent can be hydrophobic or hydrophilic. The device used can be a device as described above, comprising at least two cleaning sections.

[0029] In a particularly advantageous embodiment, the cleaning device comprises at least three successive cleaning sections, wherein water is applied to the first cleaning section, a solvent is applied to the second cleaning section, and no liquid is applied to the third cleaning section. Preferably, in the method according to the invention, such a cleaning device is used in such a way that the cleaning section to which water is applied enters the inner channel between the electrodes first to dissolve any deposits. Then, the cleaning section to which solvent is applied enters to replace the water with solvent. Finally, the dry cleaning section enters the intermediate space to dry the surfaces of the electrodes. This process can be repeated several times, for example two, three, four, five, or six times.

[0030] Advantageously, the method according to the invention may comprise inserting the device into one end of a multipole device first with a handling portion, passing the device through so that the handling portion protrudes from the space at its other end, and withdrawing the device from the space at its other end.

[0031] The present invention is based on the recognition that it is undesirable to disassemble a multipole device for cleaning purposes and that cleaning should therefore be performed by a cleaning device that can be inserted into the multipole device. The present invention utilizes the further recognition that the cleaning device should preferably only move in one direction through the multipole device in order to push deposits out of the multipole device. The present invention also utilizes the still further recognition that the cleaning device can comprise at least two, but preferably at least three, separate cleaning sections, to each of which preferably at least two different cleaning fluids can be applied, and that a third or further cleaning section can be used to dry the electrodes.

[0032] The multipole electrodes cleaned according to the invention can be part of a quadrupole device, a hexapole device, an octopole device, or another multipole device. In general, the cleaning device and the method according to the invention can also be used for other parts of a mass spectrometer, such as ion lenses, provided the dimensions of the cleaning device are appropriately selected. Brief description of the drawings Fig. 1 shows a side view of an embodiment of a cleaning device according to the invention. Fig. Figure 2 shows schematically in a cross-sectional view how a cleaning device according to the invention can be inserted between the electrodes of an ion-optical multipole device. Fig. Figure 3 shows a schematic front view of the space between the electrodes of an ion-optical multipole device. Fig. 4 shows schematically in a perspective view a part of an embodiment of a cleaning device according to the invention. Fig. 5 shows schematically in a cross-sectional view an alternative embodiment of a cleaning section of a cleaning device according to the invention. Fig. 6A - 6D show schematically in front view various embodiments of cleaning sections of a cleaning device according to the invention. Fig. 7A and Fig. 7B schematically show alternative embodiments of a cleaning device according to the invention. Fig. Figure 8 shows schematically how different liquids can be applied to a cleaning device according to the invention. Fig. 9 schematically shows an embodiment of a cleaning method according to the invention. Detailed description of implementation examples

[0033] The embodiment of a cleaning device 1 according to the invention, which is shown schematically in Fig. 1, comprises various sections with different functions. The cleaning device 1 shown has three cleaning sections 20, two handling sections 30, three spacing sections 40, a directing section 50, and a connecting section 60. The cleaning sections 20 serve to clean the surfaces of multipole device electrodes, the handling sections 30 serve to handle the cleaning device 1, the spacing sections 40 serve to space the cleaning sections 20 apart from one another, the directing section 50 serves to specify a preferred direction of use on the cleaning device 1, while the connecting section 60 serves to detachably connect a handling section, which in this embodiment is the longest handling section, to the other sections of the device.

[0034] The cleaning device 1 is shown to have a body consisting of a longitudinal shaft 10 extending from the first handling section 30 through the intermediate cleaning sections 20, the spacing sections 40, and the directional section 50 to the connecting section 60. The longitudinal shaft 10 can be made of a single piece of material, for example, plastic or metal. In the example shown, it can be seen that the shaft 10 has a smaller cross-sectional diameter than all other parts of the cleaning device 1.

[0035] In the Fig. In the embodiment shown in Figure 1, handling sections 30 are provided at both ends of the device 1. In this embodiment, one handling section is considerably longer than the other handling section. In particular, a relatively short handle 31 forms the handling section, which borders the directional section 50, while a relatively long handle 32 (which is only partially shown) is connected via the connecting section 60. The relatively short handle 31 can, for example, have a length between 1 and 5 cm, for example 1.5 or 2 cm, while the relatively long handle 32 can, for example, have a length between 20 cm and 50 cm, for example approximately 35 cm or 40 cm.Since the relatively long handle 32 serves to pull the device 1 through an ion-optical multipole device or another mass spectrometer component with longitudinal electrodes, its length should be dimensioned such that the total length of the device 1 is at least equal to the length of the electrodes to be cleaned, but preferably greater. Therefore, if the electrodes to be cleaned have a length of 40 cm, for example, the length of the cleaning device 1 should be more than 40 cm, for example 50 cm. Preferably, the length of the longest handle (32 in the example shown) should be at least equal to the length of the electrodes to be cleaned, or even at least equal to the length of the multipole device if the multipole device is longer than its electrodes. A person skilled in the art will therefore select a suitable handle length depending on the length of the electrodes and / or the multipole device to be cleaned.

[0036] In the embodiment shown, the cross-sectional diameter of the handles 31 and 32 is larger than the cross-sectional diameter of the shaft 10, but smaller than the cross-sectional diameter of the cleaning sections 20. Because their cross-sectional diameter is smaller than that of the cleaning sections, unnecessary friction by the handles is avoided.

[0037] Embodiments may be provided in which a handling portion is provided only at one end of the device. However, a handle at both ends of the device facilitates use of the device. The handles may, for example, be made of plastic.

[0038] In the embodiment shown, the cleaning device 1 has three cleaning sections 20. In some embodiments, the device may have fewer or more cleaning sections, for example, only one or two cleaning sections or four or more cleaning sections. The presence of at least three cleaning sections is advantageous for certain applications, as explained below.

[0039] In the embodiment of Fig. 1, each cleaning section 20 comprises a series of flanges 21 extending substantially perpendicularly from the shaft 10 forming the body of the cleaning device 1. The flanges 21 of each cleaning section are spaced apart so as to allow flexion in use. The mutual spacing of the flanges within each cleaning section, in the embodiment shown, is greater than the thickness of the flanges to allow flexion of the flanges 21. Cellulose has been found to be a particularly suitable material for the flanges 21. However, other materials such as (either artificial or natural) leather, fabric, and / or sponge may also be used. Suitable materials may absorb liquid to a certain extent and release the liquid when the cleaning device is inserted into the internal channel of a multi-pole device.

[0040] As can be seen, when not in use, the flanges 21 have a larger cross-sectional diameter than all other parts of the device 1. This ensures that other parts of the device do not come into contact with the electrodes to be cleaned during use and therefore do not cause unnecessary friction or damage.

[0041] In the embodiment of Fig. 1, all three cleaning sections 20 have a similar structure of approximately six to ten flanges each, with the cleaning section 20 closest to the handle 31 having the highest number of flanges. The number of flanges per cleaning section may range from approximately four to approximately twenty, and is preferably approximately ten to fifteen. The cleaning sections 20 may have different structures from one another. For example, only one or two cleaning sections could have flanges, while one or more other cleaning sections may have a different structure, e.g., one without flanges, such as a tubular compressible structure. Such a tubular compressible structure may be made of, for example, cellulose, foam, or leather. In some embodiments, all cleaning sections may have a different structure than in Fig. 1 and, for example, do not have flanges, although flanges have been shown to be effective. Alternatively or additionally, structures that have a similar effect to flanges, such as ribbed elastic structures, may be used. The cleaning sections 20 have identical cross-sectional diameters in the embodiment, but this is not required. Therefore, in some embodiments, the cross-sectional diameters of the cleaning sections may vary between and / or within sections.

[0042] The cleaning sections 20 are spaced apart from one another by spacer sections 40, each of which comprises a spacer element 41 in the embodiment shown. The spacer elements 41 may, for example, consist of tubular elements through which the shaft 10 extends, or of widened portions of the shaft 10. The spacer sections 40 serve to facilitate the application of liquids to the cleaning sections and to provide a time delay between the use of the different liquids when the cleaning device is passed between electrodes.

[0043] The directional section 50, which provides a preferred direction D in which the device 1 can be passed between electrodes, is shown to comprise a flange 51 and a blocking element 52. The flange is flexible and can therefore bend when the device is in use; however, due to the blocking element 52 being located immediately adjacent to the flange 51, the flange can only bend in a direction away from the blocking element 52. Consequently, the flange 51 causes little friction when bent away from the blocking element 52, but significantly more friction when bent toward the blocking element 52. In this way, a preferred direction of use D is obtained.

[0044] A directional section 50 may comprise more than one flange 51 and more than one blocking element 52. The cross-sectional diameter of the flange 51 may be identical to the cross-sectional diameter of the flanges 21, but may also differ, for example, be larger, so that the directional effect is greater.

[0045] In one embodiment, the diameter of a flange 21 may be approximately 9 mm, while a spacer portion has a diameter of approximately 7 mm, and the body 10 may have a diameter of approximately 4 mm. Other diameters are, of course, possible, and the outer cross-sectional diameter of the flanges 21 depends on the dimensions of the ion-optical multipole device to be cleaned, in particular the diameter of the inner channel defined by the electrodes.

[0046] A connecting portion 60 connects the handle 32 to the body 10 of the device. The connecting portion 60 includes a connecting element 61, which may include a screw thread so that the handle 32 may be removable. In some embodiments, the handle 32 may be formed integrally with the body 10, in which case the connecting portion 60 is omitted. In some embodiments, the further spacer element 41' adjacent to the connecting portion may be omitted. In some embodiments, therefore, the handle 32 may be arranged directly adjacent to a cleaning portion 20.

[0047] Fig. Figure 2 schematically shows how a cleaning device according to the invention can be used to clean electrodes of an ion-optical multipole device, such as a mass filter or a similar device. A cleaning device 1 is passed between the electrodes 100 of an ion-optical multipole device in the forward direction D. As the cleaning device 1 enters the space (i.e., the inner channel) between the electrodes 100, the flanges 21 of the cleaning device 1 are bent so that they press against the outer surfaces of the electrodes. This pressure increases the contact area between the flanges 21 and the electrodes 100 and improves the cleaning effect of the flanges.

[0048] Out of Fig. 2 it is also apparent that the total length of the cleaning device 1 should be at least equal to the total length of the electrodes 100, but that preferably a handle of the cleaning device 1 should be longer than the electrodes in order to enable easy handling of the cleaning device.

[0049] Fig. Figure 3 is a front view of the electrodes 100, in the case shown a quadrupole arrangement. The dimensions of the circular space between the electrodes are defined by the so-called inscribed diameter, which is twice the so-called inscribed radius r0. A circle with a diameter equal to twice the inscribed radius r0 fits exactly between the electrodes 100. Referring again to Fig. 2, it is clear that a cleaning device with a cross-sectional diameter equal to twice the inscribed radius r0 will not exert a significant force on the electrodes 100. For this reason, the cross-sectional diameter of the cleaning sections of the cleaning device should, in use, be larger than the inscribed diameter, for example, at least 5% larger, but preferably at least 10% larger. The extent to which the cross-sectional diameter of the cleaning device exceeds the inscribed diameter may also depend on the material of the cleaning sections. Cleaning sections made of softer materials and / or less elastic materials may need to exceed the inscribed diameter by a greater amount than, for example, harder materials and / or materials with high elasticity.Cleaning sections to which a liquid is applied prior to use may swell due to the absorption of the liquid and may not exceed the specified diameter when dry. Other cleaning sections may shrink due to the application of a liquid; in this case, their diameters when dry should exceed the inscribed diameter.

[0050] One end of a cleaning device 1 according to the invention is in Fig. 4 in more detail. It is shown that the cleaning device 1 comprises a cleaning section 20 with flanges 21, a directional section comprising a flange 51 and a blocking element 52, and a handle 31. It can be seen that the directional section flange 51 is arranged immediately next to the blocking element 52, thereby preventing the flange 51 from bending towards the blocking element 52. As can be seen, the flange 51 can bend away from the blocking element 52 in the other direction. Although in the Fig. 1 and Fig. 4 only a single directional section is shown, in some embodiments more than one directional section may be provided, for example two, three or four directional sections, in order to increase the directional preference of the device and to avoid the device being inserted in the wrong direction.

[0051] In Fig. 4 shows that both the flange 51 of the directional section and the flanges 21 of the cleaning section consist of substantially flat discs extending substantially perpendicularly from the body 10 of the device 1. However, this is not essential, and in other embodiments, the flanges may have different shapes and / or may extend at an angle other than approximately 90 0 extend from the body of the cleaning device. The angle at which flanges or other objects protrude from the body may be less than 90 0 be, for example between about 30 0 and 60°, for example about 45 0.

[0052] An example of flanges that are at an angle other than 90 0 run, is in Fig. 5, where 21 flanges are arranged at an angle of about 45 0from the body 10 of the cleaning device 1 (of which only a part is shown for the sake of clarity of the drawing). In the embodiment shown, the flanges 21 do not consist of substantially flat discs, but of substantially conical structures. In such an embodiment, the flanges 21 provide a preferred insertion direction, in which case the directional section (50 in Fig. 1) may be omitted. However, in some embodiments, both flanges may provide a preferred direction, and a directional section may be present.

[0053] In some embodiments, at least one cleaning section may not have flanges, but may have an alternative structure, for example, consisting of a tubular shell made of a suitable material such as cellulose, foam, or leather.

[0054] Examples of different cross-sectional shapes of cleaning sections and / or their flanges are shown in the Fig. 6A to 6D are shown schematically. Fig. Figure 6A shows a substantially circular cross-section of a flange 21 arranged on a body 10. The advantage of this cross-sectional shape is that it is suitable for cleaning various electrode arrangements, such as quadrupoles, hexapoles, and octopoles. The embodiment of Fig. 6B, with a substantially square cross-sectional shape of which the four corners have been replaced by concave cutouts, is particularly suitable for cleaning a quadrupole array since it can reach a larger part of the surface of the quadrupole electrodes.

[0055] The essentially square cross-sectional shape of the embodiment of Fig. 6C is also suitable for cleaning quadrupole devices. The substantially hexagonal cross-sectional shape of the embodiment of Fig. 6D is particularly suitable for cleaning hexapole arrangements. It goes without saying that other cross-sectional shapes are also possible.

[0056] The Fig. The embodiment of the cleaning device shown in Figure 1 has three cleaning sections (20 in Fig. 1). As mentioned above, other embodiments may have more or fewer than three cleaning sections. The embodiment of Fig. 7A, for example, has two cleaning sections 20, but is otherwise identical to the embodiment of Fig. 1. The embodiment of Fig. 7B has only a single cleaning section 20, but is otherwise identical to the embodiment of Fig. 1.

[0057] A particularly advantageous use of the cleaning device according to the invention is in Fig. 8, in which a cleaning device 1 according to the invention is shown, which comprises a first handle 31, a directional section 50, cleaning sections 20, spacer elements 41, and a second handle 32 (which is only partially shown). In the embodiment shown, the device 1 comprises three cleaning sections 20, which do not have flanges, but consist of tubes made of absorbent material such as foam or leather. The use of the cleaning sections 20 shown in Fig. The cleaning device shown in Figure 8 is equally possible with a cleaning device of which, for example, at least one cleaning section comprises flanges.

[0058] Advantageously, the device 1 is used together with a water supply 210 and a solvent supply 220. The directional section 50 is arranged such that the preferred direction of insertion of the device between electrodes of an ion-optical multipole device is with the (second) handle 32 first, i.e., in direction D. Water is applied to the first cleaning section 20A, which is to be in contact with the electrodes, while a solvent is applied to the second cleaning section 20B. The cleaning sections 20A and 20B are therefore arranged to absorb some liquid and are made of a liquid-absorbing material. In the embodiment shown, no liquid is applied to the third cleaning section 20C, although in some embodiments, a third liquid may be applied to the third cleaning section 20C.

[0059] When the device 1 is inserted into the space between the electrodes (see for example Fig. 2), the compression of the cleaning sections by the electrodes of the multipole device results in at least some release of the respective absorbed liquid. Thus, in the embodiment shown, water is first applied to the electrodes, then the water is replaced with solvent, and subsequently the electrodes are dried by the dry cleaning section, i.e., cleaning section 20C, to which no liquid has been applied.

[0060] It should be understood that the invention is not limited to the application of two liquids and the use of a single dry cleaning section. Only a single liquid may be applied to a single cleaning section, with another cleaning section being used for drying. When using a device with only a single cleaning section, drying can be omitted.

[0061] The solvent may be a suitable organic solvent (i.e., a carbon-based solvent), such as an alcohol, ether, or ester, an aliphatic or aromatic solvent, or any other suitable solvent. The water may be ultrapure distilled water. In some embodiments, the cleaning fluids are mixtures of water and a solvent in various mixing ratios. Cleaning fluids, such as water, may contain surfactants. Surfactant-containing cleaning fluids are preferably followed by pure water and then preferably by a solvent.

[0062] Solvents can be selected based on their compatibility with the materials from which the cleaning device is made and vice versa.

[0063] The embodiment of a method 300 according to the invention, which is shown in Fig. 9, begins at step 301 when the method is initiated. In step 302, a first cleaning liquid, such as water, is applied to a first cleaning section of a cleaning device according to the invention, as described above with reference to Fig. 8. In step 303, a second cleaning fluid, such as a solvent, is applied to a second cleaning section. In this embodiment, no fluid or other substance is applied to a third cleaning section of the device, if present. This completes the preparation of the cleaning device.

[0064] In step 304, the cleaning device is inserted into the space between the electrodes of an ion-optical multipole device or similar device. It is inserted far enough so that one end of the cleaning device exits the other end of the electrodes, allowing the cleaning device to be passed through the space between the electrodes of the multipole device in step 305.

[0065] These steps can be performed more than once, for example two, three, four, five, or more than five times, for example ten or even fifty times. Steps 304 and 305 can be performed as often as necessary to obtain a specific result, which can be determined by visual detection or automatic detection (for example, using image processing). In a preferred embodiment, a predetermined number of iterations, preferably three, are performed. Each time the cleaning device exits the multipole device, a check is made in step 306 as to whether the predetermined number of iterations has been reached. If this is the case ("Yes"), the method ends at step 307. If the predetermined number of iterations has not been reached ("No"), the method returns to step 304, in which the cleaning device is introduced into the multipole device.In some embodiments, not only steps 304 and 305 may be repeated, but also steps 302 (application of the first cleaning fluid) and 303 (application of the second cleaning fluid). In some embodiments, step 302 may therefore follow a "no" decision in step 306. In certain embodiments, a "no" decision in step 306 leads back to step 302 if a first condition is met (e.g., an even number of iterations have been performed) and leads back to step 304 if a second condition is met (e.g., an odd number of iterations have been performed). This results in cleaning fluids being applied, but not every time the cleaning device is introduced into the multipole arrangement. Other variants of the method according to the invention are also possible.

[0066] After cleaning the electrodes of a multipole device, the cleaning device can be discarded. Some embodiments of the cleaning device may be suitable for multiple use.

[0067] This embodiment of the method according to the invention is given only as an example. Those skilled in the art will therefore understand that the invention is not limited to the embodiments described above and that numerous additions and modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

[1] Cleaning device (1) for cleaning a plurality of elongated electrodes (100) of an ion-optical multipole device, wherein the cleaning device (1) comprises at least one substantially longitudinally extending cleaning section (20), at least one handling section (30) extending axially from the at least one cleaning section (20), and at least one directional section (50) extending axially from the at least one cleaning section (20), characterized byin that the cleaning section (20) comprises a series of cleaning elements protruding from a body (10), wherein the directional section (50) comprises at least one flexible element protruding from the body (10) and at least one blocking element (52) arranged next to the flexible element to block any bending of the flexible element in the direction of the blocking element (52), wherein the at least one cleaning section (20) has a larger cross-section than the at least one handling section (30) and the at least one directional section (50) can allow a longitudinal movement of the cleaning device (1) in a first axial direction and offer resistance to a longitudinal movement of the cleaning device (1) in a second, opposite axial direction. [2] Cleaning device (1) according to claim 1, wherein at least one cleaning section (20) has a substantially polygonal cross-sectional shape, such as square, hexagonal or octagonal. [3] Cleaning device (1) according to claim 1 or 2, wherein at least one cleaning section (20) has a substantially circular cross-sectional shape. [4] Cleaning device (1) according to one of the preceding claims, wherein at least one cleaning section (20) has a substantially elliptical cross-sectional shape. [5] Cleaning device (1) according to one of the preceding claims, comprising at least two cleaning sections (20), wherein two cleaning sections (20) have different cross-sectional shapes and / or different cross-sectional dimensions. [6] Cleaning device (1) according to one of the preceding claims, comprising at least two cleaning sections (20), wherein two cleaning sections have identical cross-sectional shapes and / or cross-sectional dimensions. [7] Cleaning device (1) according to one of the preceding claims, comprising two or more cleaning sections (20) separated by at least one spacer section, wherein the at least one spacer section has a smaller cross-section than the cleaning sections (20). [8] Cleaning device (1) according to one of claims 1-7, wherein the cleaning elements comprise cleaning flanges. [9] Cleaning device (1) according to claim 8, wherein at least some cleaning flanges protrude substantially vertically from the body. [10] Cleaning device (1) according to claim 8 or 9, wherein at least some cleaning flanges protrude from the body (10) at an acute angle. [11] Cleaning device (1) according to one of claims 8 to 10, wherein at least some cleaning flanges are substantially planar. [12] Cleaning device (1) according to one of claims 9 to 11, wherein at least some cleaning flanges are curved. [13] Cleaning device (1) according to one of the preceding claims, wherein at least one cleaning section (20) is arranged so that it is compressible. [14] Cleaning device (1) according to one of the preceding claims, wherein at least one cleaning section (20) is capable of absorbing and releasing a cleaning liquid. [15] Cleaning device (1) according to one of the preceding claims, wherein at least one cleaning section comprises cellulose, natural or synthetic sponge, leather and / or fabric. [16] Cleaning device (1) according to one of the preceding claims, comprising three cleaning sections (20) separated by spacer sections. [17] Cleaning device (1) according to any one of claims 1-16, wherein the flexible element comprises a flange (21) whose cross-section is larger than that of the blocking element. [18] Cleaning device (1) according to one of the preceding claims, wherein the at least one handling section (30) is substantially longer than the combined cleaning sections. [19] Cleaning device (1) according to claim 18, wherein the handling portion (30) comprises a substantially rigid rod. [20] Cleaning device (1) according to claim 18 or 19, wherein the handling portion (30) comprises a substantially flexible element such as a cord or a rope. [21] Cleaning device (1) according to one of the preceding claims, comprising two handling sections (30), wherein one handling section (30) at one end of the cleaning sections (20) is at least five times as long as the other handling section (30) at the opposite end of the one or more cleaning sections (20), preferably at least ten times as long. [22] Cleaning device (1) according to one of the preceding claims, wherein at least one handling section (30) has a length which exceeds the length of the electrodes (100) to be cleaned. [23] Cleaning device (1) according to one of the preceding claims, wherein at least one cleaning section (20) has a cross-section which exceeds the inscribed diameter of the electrodes (100) to be cleaned. [24] A method for cleaning electrodes of an ion-optical multipole device, the method comprising the use of a cleaning device (1) according to any one of the preceding claims. [25] The method of claim 24, further comprising the use of at least one cleaning liquid to be applied to the at least one cleaning portion (20) of the cleaning device (1). [26] A method according to claim 25, wherein the method further comprises the use of at least two different cleaning liquids to be applied to at least two respective cleaning sections (20) of the cleaning device (1). [27] A method according to claim 25 or 26, wherein at least one cleaning liquid comprises water, either substantially pure water or water containing a soap, a solvent or other cleaning-enhancing substance. [28] A method according to any one of claims 25 to 27, wherein at least one cleaning liquid comprises a solvent. [29] The method of claim 28, wherein the solvent is hydrophobic. [30] The method of claim 28, wherein the solvent is hydrophilic. [31] Method according to one of claims 24 to 30, wherein the cleaning device (1) comprises at least three successive cleaning sections (20), wherein water is applied to the first cleaning section (20), a solvent is applied to the second cleaning section (20) and no liquid is applied to the third cleaning section (20). [32] A method according to any one of claims 24 to 31, comprising inserting the cleaning device (1), with a handling portion (30) first, into one end of a gap between electrodes (100) of an ion-optical multipole device, passing the cleaning device (1) through the gap so that the handling portion (30) protrudes from the gap at its other end, and withdrawing the cleaning device (1) from the gap at the other end. [33] A method according to any one of claims 24 to 32, wherein the ion-optical multipole device is a quadrupole device, a hexapole device, an octopole device or another multipole device.

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