Ion transmission multipole system, mass spectrometer and application thereof

Abstract

The present invention discloses an ion transmission multipole system, a mass spectrometer and an application thereof, and belongs to the technical field of mass analysis instruments. The ion transmission multipole system comprises a reflection device and an ion transmission multipole; the ion transmission multipole has a plurality of electrodes, and an ion channel for ions to pass through is formed between all electrodes of the ion transmission multipole, and the reflection device is arranged in the ion channel; the reflection device is an annular electrode, and the cross section of the annular electrode is parallel to the cross section of the ion channel. The ion transmission multipole system has a simple structure, which is conducive to simplifying circuit design; it is suitable for high vacuum environment; it can control the movement of ions without very high voltage, and it is efficient and convenient; after the ions are reflected by the reflection device or pass through the reflection device, the ion group does not expand significantly, and the divergence is effectively controlled.

Description

Technical Field

[0001] The present invention relates to the technical field of mass analysis instruments, and in particular to an ion transmission multipole system, a mass spectrometer and applications thereof. Background Art

[0002] In a stable ion transmission multipole system, if no additional interference is added, the ions will continue to oscillate and move forward in the direction of the initial kinetic energy under the action of the radio frequency field. However, in some cases, the ions are not expected to move forward all the time. For example, in a reaction cell, the ions are expected to be stored in it to increase the reaction time; or in the injection quadrupole, small mass ions are allowed to reflect, so as to achieve the purpose of injection in a wider mass range. Because small mass ions have a fast speed and large mass ions have a slow speed after obtaining the same energy, it is more difficult to inject them into the mass analyzer for detection at the same time. Therefore, in an injection device with a limited length structure, by allowing small mass ions to reflect and extend their residence time in the device, larger mass ions can enter the device and be injected at the same time, thereby obtaining a wider detection mass range.

[0003] There are five main methods currently used to reflect (store) ions in ion transport multipoles:

[0004] 1. Segmented structure: Use multi-segment transmission multipole, such as the most commonly used three-segment linear ion trap, add higher voltage DC bias to the front and end sections to form an electric potential barrier or potential well to reflect or store ions; another segmented structure is to divide the multipole into multiple sections, and control the DC voltage on each section to form the desired potential well to achieve our desired purpose.

[0005] 2. Conical trap: By tilting the multipole rods to form a cone, the distance between the head and tail ends is different to generate a potential difference, thereby reflecting ions. If ions are to be stored, additional conical multipole rods are required.

[0006] 3. Electric field penetration forms potential barriers: One way is to add a ring electrode outside the multipole, and determine the position and depth of the potential well by the level of the DC bias of the ring electrode, thereby controlling the reflection and storage of ions. Another way is to insert a long strip electrode into the multipole. The long strip electrode is at a certain angle, and like the conical well, it can form an axial acceleration electric field and an axial deceleration electric field, so as to achieve the function of pushing ions forward or reflecting (storing) ions.

[0007] 4. Apply asymmetric RF voltage: Often, the RF voltages on two pairs of multipole rods in different directions have the same amplitude and opposite phase, and the axial potential is 0V. If an asymmetric amplitude voltage is applied, or a RF is superimposed on an electrode, a RF barrier can be formed to complete the reflection or storage function of ions.

[0008] 5. Add end cap electrodes: Add blocking end cap electrodes before, after, or in the middle of the multipole. Dig a hole in the middle of the electrode and apply a DC voltage to form an electric potential barrier to reflect (store) the ions. At the same time, the ions can also pass through by turning off the DC bias.

[0009] The five methods currently used all have their own advantages and disadvantages and use environments. First, in the application environment of high vacuum, methods 4 and 5 will cause the ions to be heated, and are not applicable in high vacuum environments. This is because if the ions are heated, the various dispersions of the ions, including energy dispersion, spatial dispersion, and angular dispersion, will increase. There is no background gas to cool the ions under high vacuum, which directly affects the resolution and sensitivity of the detection. Secondly, the problem of work efficiency. Methods 2, 3, and 4 all have efficiency problems. The potential barrier formed may be only about 1% of the DC voltage of the electrode. For ions of a certain energy, a relatively high voltage needs to be added to reflect, or for some electrodes, it is dangerous to add high voltage, and the reflection efficiency will also be limited. In addition, in terms of mechanical structure, if you encounter curved or special-shaped electrodes when using methods 1 and 2, the processing and assembly are complicated. Finally, in terms of circuit design, the circuit design of method 1 is the most complex, involving multiple radio frequency and DC.

[0010] In view of this, the present invention is proposed. Summary of the invention

[0011] One of the objectives of the present invention is to provide an ion transmission multipole system to solve at least one of the above technical problems.

[0012] A second object of the present invention is to provide a mass spectrometer containing the above-mentioned ion transmission multipole system.

[0013] A third object of the present invention is to provide an application of the above-mentioned mass spectrometer.

[0014] This application can be implemented as follows:

[0015] In a first aspect, the present application provides an ion transmission multipole system, which includes a reflection device and an ion transmission multipole;

[0016] The ion transmission multipole has a plurality of electrodes, and an ion channel for ions to pass through is formed between all the electrodes of the ion transmission multipole, and the reflection device is arranged in the ion channel;

[0017] The reflection device is a ring electrode, and the cross section of the ring electrode is parallel to the cross section of the ion channel.

[0018] In an optional embodiment, the thickness of the annular electrode is 1-2 mm.

[0019] In an alternative embodiment, the thickness of the ring electrode is 1 mm.

[0020] In an alternative embodiment, the ring electrode does not contact each electrode in the ion transport multipole.

[0021] In an optional embodiment, the ring electrode is a square ring electrode or a circular ring electrode, the ion transport multipole includes four identical cylindrical electrodes, the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel is 0.8-0.9:1, and the ratio of the diameter of the circular ring electrode to the diameter of the circle inscribed in the cross-section of the ion channel is 0.8-0.9:1.

[0022] In an optional embodiment, the ring electrode is a square ring electrode or a circular ring electrode, the ion transport multipole includes six identical cylindrical electrodes, the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel is 0.8-0.9:1, and the ratio of the diameter of the circular ring electrode to the diameter of the circle inscribed in the cross-section of the ion channel is 0.8-0.9:1.

[0023] In an optional embodiment, the ring electrode is a square ring electrode or a circular ring electrode, the ion transport multipole includes eight identical cylindrical electrodes, the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel is 0.8-0.9:1, and the ratio of the diameter of the circular ring electrode to the diameter of the circle inscribed in the cross-section of the ion channel is 0.8-0.9:1.

[0024] In an optional embodiment, an annular electrode is provided at both the inlet and outlet ends of the ion channel, or an annular electrode is provided in the middle region of the ion channel along the length direction, or annular electrodes are provided at the inlet, outlet and middle region of the ion channel along the length direction.

[0025] In an optional embodiment, the ion transport multipole system further comprises a fixing member for fixing the annular electrode, wherein the fixing member is connected to an outer wall of the annular electrode.

[0026] In a second aspect, the present application provides a mass spectrometer, which includes an ion detector and an ion transmission multipole system according to any one of the aforementioned embodiments;

[0027] The inlet of the ion detector is connected to the outlet end of the ion channel of the ion transmission multipole system.

[0028] In a third aspect, the present application provides an application of a mass spectrometer according to the aforementioned embodiment, for example, for analyzing and detecting ions in the mass range of 1000-3000 Th.

[0029] The beneficial effects of this application include:

[0030] The present application uses an annular electrode as a reflecting device, and has a simple structure. The annular electrode can be set into a variety of shapes, and the function of the gate electrode in the prior art can be achieved by simply fixing it in the desired position. Since only a DC voltage needs to be passed through the annular electrode, it can be directly powered by a DC circuit, without the need for multiple DC or RF circuits, which greatly simplifies the circuit design. The setting of the annular electrode can control the movement of ions without a very high voltage, which not only reduces the voltage requirement, but also controls the movement of ions more efficiently. After the ions are reflected by the reflecting device or pass through the reflecting device, the ions after reflection or passing through will not be heated to a large extent, the ion clusters will not expand significantly, and the divergence will be effectively controlled.

[0031] Therefore, the solution provided in this application can integrate the advantages of efficient control of ion reflection and ejection, effective suppression of divergence, simple structure, simple circuit, etc., and has a high value for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 A schematic diagram of the structure of the ion transmission multipole system provided in the present application at a first viewing angle;

[0034] Figure 2 A schematic diagram of the structure of the ion transmission multipole system provided in the present application at a second viewing angle;

[0035] Figure 3 This is a schematic structural diagram of the ion transmission multipole system of the control group in Experimental Example 1 of the present application at a first viewing angle;

[0036] Figure 4 This is a schematic structural diagram of the ion transmission multipole system of the control group in Experimental Example 1 of the present application at a second viewing angle;

[0037] Figure 5 This is the reflected ion trajectory diagram corresponding to the experimental group in Experimental Example 1 of this application;

[0038] Figure 6 This is the reflected ion trajectory diagram corresponding to the control group in Experimental Example 1 of this application;

[0039] Figure 7 This is a trajectory diagram of ions corresponding to the experimental group in Experimental Example 1 of this application passing through the annular electrode;

[0040] Figure 8This is a trajectory diagram of ions corresponding to the control group in Experimental Example 1 of the present application passing through the annular electrode;

[0041] Fig. 9 This is the reflected ion trajectory diagram corresponding to Comparative Example 1 in Experimental Example 2 of this application;

[0042] Fig.10 This is the reflected ion trajectory diagram corresponding to Comparative Example 2 in Experimental Example 2 of this application;

[0043] Fig.11 This is the reflected ion trajectory diagram corresponding to Comparative Example 3 in Experimental Example 2 of this application;

[0044] Fig.12 This is a trajectory diagram of ions passing through the annular electrode corresponding to Comparative Example 1 in Experimental Example 2 of the present application;

[0045] Fig.13 This is a trajectory diagram of ions passing through the annular electrode corresponding to Comparative Example 2 in Experimental Example 2 of the present application;

[0046] Fig.14 This is a trajectory diagram of ions passing through the annular electrode corresponding to Comparative Example 3 in Experimental Example 2 of the present application;

[0047] Fig.15 This is the reflected ion trajectory diagram corresponding to Comparative Example 4 in Experimental Example 3 of this application;

[0048] Fig.16 This is the reflected ion trajectory diagram corresponding to Comparative Example 5 in Experimental Example 3 of this application;

[0049] Fig.17 This is a trajectory diagram of ions passing through the annular electrode corresponding to Comparative Example 4 in Experimental Example 3 of the present application;

[0050] Fig.18 This is a trajectory diagram of ions passing through the annular electrode corresponding to Comparative Example 5 in Experimental Example 3 of the present application.

[0051] Icon: 1-first electrode; 2-second electrode; 3-ring electrode; 4-end cap electrode. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0053] The ion transmission multipole system, mass spectrometer and their applications provided by the present application are described in detail below.

[0054] Please refer to Figure 1 and Figure 2 The present application proposes an ion transmission multipole system, which includes a reflection device and an ion transmission multipole.

[0055] The ion transmission multipole has a plurality of electrodes. An ion channel for ions to pass through is formed between all the electrodes of the ion transmission multipole. The reflecting device is arranged in the ion channel.

[0056] In the present application, the reflecting device is an annular electrode 3, and the cross section of the annular electrode 3 is parallel to the cross section of the ion channel.

[0057] The thickness of the annular electrode 3 may be 1-2 mm, such as 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2 mm, etc., or any other value within the range of 1-2 mm. Preferably, the thickness of the annular electrode 3 is 1 mm.

[0058] It should be noted that the annular electrode 3 having the above thickness is very thin, which can lessen the impact on the quadrupole field near the location where it is located, so that the generated edge field has a relatively small impact on the movement of ions. When the thickness of the annular electrode 3 is less than 1 mm, the difficulty of processing and assembly will be greatly increased.

[0059] In an optional embodiment, the annular electrode 3 does not contact any electrode in the ion transport multipole, that is, there is a gap between the outer wall of the annular electrode 3 and the outer wall of each electrode in the ion transport multipole.

[0060] It should be noted that if the annular electrode 3 contacts the electrodes in the ion transport multipole, the quadrupole field near the location thereof will be greatly affected, thereby affecting the movement of ions.

[0061] For reference, in the present application, the annular electrode 3 may be a circular ring electrode, a square ring electrode or a triangular ring electrode, and may also be an annular electrode 3 of other shapes. However, in a preferred embodiment, the annular electrode 3 is a circular ring electrode or a square ring electrode.

[0062] The type of ion transport multipole can be a quadrupole, a hexapole or an octopole. Among them, the quadrupole can be understood as four columnar electrodes arranged in parallel. Among them, "electrodes arranged in parallel" means that the axes of each columnar electrode are parallel to each other. The cross-section of the columnar electrode can be hyperbolic, circular or square, etc.

[0063] In an optional embodiment, when the annular electrode 3 is a square annular electrode or a circular annular electrode, and the ion transmission multipole includes four identical cylindrical electrodes (i.e., the ion transmission multipole is a quadrupole), the ratio of the side length of the square annular electrode to the side length of the square inscribed in the cross section of the ion channel can be 0.8-0.9:1, such as 0.8:1, 0.82:1, 0.85:1, 0.88:1 or 0.9:1, etc., or any other value within the range of 0.8-0.9:1. Similarly, the ratio of the diameter of the circular annular electrode to the diameter of the circle inscribed in the cross section of the ion channel can also be 0.8-0.9:1, such as 0.8:1, 0.82:1, 0.85:1, 0.88:1 or 0.9:1, etc.

[0064] Similarly, when the annular electrode 3 is a square ring electrode or a circular ring electrode, and the ion transmission multipole includes six identical cylindrical electrodes (that is, the ion transmission multipole is a hexapole), the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel can be 0.8-0.9:1, and the ratio of the diameter of the circular ring electrode to the diameter of the circle inscribed in the cross-section of the ion channel can also be 0.8-0.9:1.

[0065] When the annular electrode 3 is a square ring electrode or a circular ring electrode, and the ion transmission multipole includes eight identical cylindrical electrodes (that is, the ion transmission multipole is an octopole), the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel can be 0.8-0.9:1, and the ratio of the diameter of the circular ring electrode to the diameter of the circle inscribed in the cross-section of the ion channel can also be 0.8-0.9:1.

[0066] In the present application, the setting position of the annular electrode 3 can be set as needed. For example, the annular electrode 3 can be set at both the entrance and exit ends of the ion channel, or in the middle area of ​​the ion channel along the length direction. The annular electrode 3 can also be set at the entrance, exit and middle area of ​​the ion channel along the length direction.

[0067] Furthermore, the above-mentioned ion transmission multipole system may also include a fixing member for fixing the annular electrode 3. The fixing member is connected to the outer wall of the annular electrode 3. The other end of the fixing member may be connected to the inner wall of the chamber of the ion transmission multipole system.

[0068] The number of fixing elements is not limited and can be arranged as required. The projections of all fixing elements on the cross section of the ion channel can be, for example, in the shape of a "well", "center" or "meter".

[0069] In some specific embodiments, when the annular electrode 3 is a square annular electrode, there may be four fixing members, one end of each of which is connected to the four corners of the square annular electrode, and the other end of each of which is connected to the inner wall of the chamber of the ion transport multipole system.

[0070] It should be noted that other structures of the ion transport multipole system not described in detail in this application can refer to the prior art and will not be described in detail here. In addition, the annular electrode 3 is suitable for use in linear ion traps, reaction cells, transport multipoles and radial injection multipoles.

[0071] The operation mode of the ion transmission multipole system provided in this application is as follows:

[0072] Taking the ion transmission multipole as a quadrupole as an example, it includes a group of first electrodes 1 arranged oppositely and a group of second electrodes 2 arranged oppositely. First, a radio frequency voltage of a certain amplitude, frequency and phase is applied to the first electrode 1, and at the same time, a radio frequency voltage with the same amplitude, frequency and opposite phase as the first electrode 1 is applied to the second electrode 2 to form a quadrupole field to transmit ions. The ions will oscillate and move along the quadrupole under the action of the quadrupole field. If it is in the reflection working mode, a DC voltage is applied to the annular electrode 3, and the ions will be decelerated by the electric field when approaching the annular electrode 3. If the voltage is large enough, the ions can turn back and complete the reflection. An adjustable DC voltage can be applied to the annular electrode 3 to ensure that all ions close to the annular electrode 3 can be reflected. If the ions need to pass through the quadrupole, it is only necessary to remove the DC voltage of the annular electrode 3. Since the length and thickness of the annular electrode 3 are very small, the quadrupole field near the position of the annular electrode 3 is affected very little, so the edge field that can be generated has a relatively small effect on the movement of the ions.

[0073] As mentioned above, the reflection device (annular electrode 3) in the ion transport multipole system provided by the present application has at least the following characteristics:

[0074] (1) Suitable for high vacuum environment.

[0075] (2) Simple mechanical structure: The annular electrode 3 can be set in various shapes, and the function of the gate electrode in the prior art can be achieved by only fixing a thin annular electrode 3 at the required position.

[0076] (3) Circuit design is greatly simplified. Since there is only a DC voltage on the annular electrode 3, it can be powered directly by a DC circuit without the need for multiple DC or RF circuits.

[0077] (4) The ion movement can be controlled without a very high voltage, which not only reduces the voltage requirement but also controls the ion movement more efficiently. The simulation results show that if ions with 4 eV energy are reflected, a minimum voltage of about 9 V is required on the annular electrode 3 of the present application, while for the conical trap or electric field penetration method in the prior art, a voltage of more than 400 V is required on the electrode to complete the reflection.

[0078] (5) After the ions are reflected by the reflecting device or pass through the reflecting device, the ions will not be heated to a large extent, the ion cluster will not expand to a large extent, and the divergence will be effectively controlled.

[0079] In addition, the present application also provides a mass spectrometer, which includes an ion detector and the above-mentioned ion transmission multipole system.

[0080] The inlet of the ion detector is connected to the outlet end of the ion channel of the ion transmission multipole system.

[0081] The ion detector receives and detects ions separated by the ion transmission multipole system and amplifies their output signals.

[0082] Furthermore, the mass spectrometer may also include an ion source, a data processing system, a vacuum system, etc. The locations and functions of the above structures may refer to the prior art and will not be elaborated herein.

[0083] In addition, the present application also provides applications of the above-mentioned mass spectrometer, for example, it can be used to analyze and detect ions with a mass range of 1000-3000Th.

[0084] Test Example 1

[0085] Experimental group: using the ion transmission multipole system provided by the present application (such as Figure 1 and Figure 2 ), which includes a reflection device and an ion transmission multipole. The ion transmission multipole is a quadrupole, including two symmetrically arranged cylindrical first electrodes 1 and two symmetrically arranged cylindrical second electrodes 2. The axes of the first electrode 1 and the second electrode 2 are parallel to each other, and the materials and sizes of the first electrode 1 and the second electrode are consistent. An ion channel for ions to pass through is formed between the two first electrodes 1 and the two second electrodes 2. The reflection device is a square ring electrode with a thickness of 1 mm, which is arranged in the above-mentioned ion channel and is located in the middle area in the length direction of the ion channel. The square ring electrode is not in contact with the first electrode 1 and the second electrode 2, and the cross section of the ring electrode 3 is parallel to the cross section of the ion channel. The ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross section of the ion channel is 0.9:1. The four corners of the ring electrode 3 are connected with fixings to fix the ring electrode 3.

[0086] Control group: The only difference between the control group and the experimental group is that the annular electrode 3 is replaced by the end cap electrode 4 in the prior art, and the setting position remains unchanged. Figure 3 and Figure 4 shown.

[0087] The above experimental group and control group were simulated, the ion mass range was selected to be 1000-3000Th, and the side section of the model was selected. The ion trajectory is shown in Figure 5 and Figure 6 As shown, Figure 5 is the reflected ion trajectory diagram corresponding to the experimental group, Figure 6 This is the reflected ion trajectory diagram corresponding to the control group.

[0088] Depend on Figure 5 and Figure 6 It can be seen that the annular electrode 3 provided by the experimental group has smaller ion divergence and narrower beam width after reflection than the end cap electrode 4 provided by the control group, and the ion injection loss rate is lower when used as an injection device.

[0089] Furthermore, the ion trajectories of the ions passing through the annular electrode 3 of the experimental group and the end cap electrode 4 of the control group were simulated, and the trajectories were as follows: Figure 7 and Figure 8 As shown, Figure 7 is the trajectory diagram of the ions corresponding to the experimental group passing through the annular electrode 3, Figure 8 This is the trajectory diagram of the ions corresponding to the control group passing through the end cap electrode 4.

[0090] Depend on Figure 7 and Figure 8 It can be seen that the ion beam oscillation amplitude increases slightly when the ions pass through the annular electrode 3, but it still runs stably. The original maximum width of the ion beam is about 1-1.1 mm, and it is about 10% wider after passing through, which is within an acceptable range. For the end cap electrode 4, the effect is similar, and the ion beam width increases by about 10-15% after passing through.

[0091] In general, the annular electrode 3 structure provided in the present application can effectively control the reflection and penetration of ions, and its effect as a reflection device is obviously better than that of the ordinary end cap electrode 4.

[0092] Test Example 2

[0093] Taking the experimental group in Experimental Example 1 as an example, comparative examples 1-3 are set. The difference between Comparative Example 1 and the experimental group in Experimental Example 1 is that the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel is 0.6:1; the difference between Comparative Example 2 and the experimental group in Experimental Example 1 is that the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel is 0.7:1; the difference between Comparative Example 3 and the experimental group in Experimental Example 1 is that the ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross-section of the ion channel is 0.8:1.

[0094] The same method and conditions as in Experimental Example 1 were used to simulate the above Comparative Examples 1-3. The ion trajectories are shown in FIG. Figure 9-11 As shown, Fig. 9 is the reflected ion trajectory diagram corresponding to comparative example 1, Fig.10 is the reflected ion trajectory diagram corresponding to comparative example 2, Fig.11This is the reflected ion trajectory diagram corresponding to Comparative Example 3.

[0095] Furthermore, the ion trajectory of the ions passing through the annular electrode 3 of Comparative Examples 1-3 is simulated, and the trajectory is as follows: Figure 12-14 As shown, Fig.12 is the trajectory diagram of ions passing through the annular electrode 3 corresponding to comparative example 1, Fig.13 is the trajectory diagram of ions passing through the annular electrode 3 corresponding to comparative example 2, Fig.14 This is the trajectory diagram of ions passing through the annular electrode 3 corresponding to comparative example 3.

[0096] Figure 9-14 It can be concluded that: for gate electrodes of different sizes, the ion beam width radius after ions pass through the gate electrode is basically less than 0.7mm, and the effect is similar. For gate electrodes with a ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross section of the ion channel after ions are reflected by the gate electrode of 0.6:1 and 0.7:1, the beam width radius of ions reflected by the gate electrode is less than 0.7mm, but the ion beam width radius after ions reflected by the gate electrode of 0.8:1 and 0.9:1 can be controlled within 0.6mm, and the size of 0.9:1 is better, but because the gate electrode cannot contact the pole, the side length of the gate electrode should be between 0.8:1-0.9:1, preferably 0.9:1.

[0097] Test Example 3

[0098] Taking the experimental group in Experimental Example 1 as an example, comparative examples 4-5 are set. The difference between Comparative Example 4 and the experimental group in Experimental Example 1 is that a hexapole is used instead of a quadrupole; the difference between Comparative Example 5 and the experimental group in Experimental Example 1 is that an octopole is used instead of a quadrupole.

[0099] The same method and conditions as in Experimental Example 1 were used to simulate Comparative Examples 4-5. The ion trajectories are shown in FIG. Fig.15 and Fig.16 As shown, Fig.15 is the reflected ion trajectory diagram corresponding to Comparative Example 4, Fig.16 This is the reflected ion trajectory diagram corresponding to Comparative Example 5.

[0100] Furthermore, the ion trajectory of the ions passing through the annular electrode 3 of Comparative Example 4-5 is simulated, and the trajectory is as follows: Figure 17-18 As shown, Fig.17 is the trajectory diagram of ions passing through the annular electrode 3 corresponding to comparative example 4, Fig.18 This is the trajectory diagram of ions passing through the annular electrode 3 corresponding to comparative example 5.

[0101] Figure 15-18It can be concluded that the gate electrode in the present application can also be used in hexapole and octopole, because the field radius of hexapole and octopole is larger than that of quadrupole, and the influence of dispersed ion beams in the same initial position is weakened. For a group of ions in the same state, the ion state after reflection and passage is better than when simulated in the quadrupole. Therefore, the gate electrode provided in the present application is suitable for multipole structure.

[0102] In summary, the solution provided by the present application has the advantages of being able to efficiently control ion reflection and ejection, effectively suppress divergence, simple structure, and simple circuit. For example, the solution provided by the present application can greatly simplify the mechanical structure and circuit design of the relevant device; it can control the movement of ions without a very high voltage, which is more efficient; after the ions are reflected by the reflection device or pass through the reflection device, the ion group does not expand significantly, and the divergence is effectively controlled.

[0103] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An ion transport multipole system, characterized in that: including a reflectron and an ion transmission multipole; The ion transmission multipole has a plurality of electrodes, an ion channel for ions to pass through is formed between all the electrodes of the ion transmission multipole, and the reflecting device is arranged in the ion channel; The reflecting device is a ring electrode, and the cross section of the ring electrode is parallel to the cross section of the ion channel; The thickness of the annular electrode is 1-2 mm; The annular electrode is not in contact with any electrode in the ion transport multipole; The annular electrode is a square ring electrode or a circular ring electrode, and the ion transport multipole includes four, six or eight identical cylindrical electrodes. The ratio of the side length of the square ring electrode to the side length of the square inscribed in the cross section of the ion channel is 0.8-0.9:1, and the ratio of the diameter of the circular ring electrode to the diameter of the circle inscribed in the cross section of the ion channel is 0.8-0.9:

1.

2. The ion transmission multipole system according to claim 1, characterized in that: The thickness of the annular electrode is 1 mm.

3. The ion transmission multipole system according to claim 1 or 2, characterized in that: The annular electrode is provided at both the inlet and outlet ends of the ion channel, or the annular electrode is provided in the middle area of ​​the ion channel along the length direction, or the annular electrode is provided at the inlet, outlet and middle area of ​​the ion channel along the length direction.

4. The ion transmission multipole system according to claim 3, characterized in that: The ion transport multipole system further includes a fixing member for fixing the annular electrode, wherein the fixing member is connected to an outer wall of the annular electrode.

5. A mass spectrometer, characterized in that: An ion transmission multipole system comprising an ion detector and any one of claims 1 to 4; The inlet of the ion detector is in communication with the outlet end of the ion channel of the ion transmission multipole system.

6. Use of the mass spectrometer according to claim 5, characterized in that: The mass spectrometer is used to analyze and detect ions with a mass range of 1000-3000Th.

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