Ion extraction method, device and mass spectrometer

Abstract

The present application relates to the field of mass spectrometers, and discloses an ion extraction method, device and mass spectrometer. The method includes: controlling target ions to be input from an introduction electrode into a collision cell in a vacuum chamber; applying a first voltage to a gate electrode to enable the target ions to enter an ion storage unit from the collision cell, and applying a second voltage to an extraction electrode to enable the target ions to accumulate in the ion storage unit; after a preset time period, adjusting the magnitude of the first voltage and / or the second voltage so that the target ions are sequentially output from the extraction electrode in the order of decreasing mass-to-charge ratio. By adjusting the magnitude of the applied voltage, the output time of the target ions is correspondingly adjusted in the embodiments of the present application, facilitating the subsequent time-of-flight mass analysis device to collect the time-of-flight mass spectrometry of target ions with different mass-to-charge ratios at the same moment, and broadening the effective mass-to-charge ratio range of the mass spectrometry.

Description

Technical Field

[0001] The present application relates to the field of mass spectrometers, and in particular, to an ion extraction method, apparatus, and mass spectrometer. Background Art

[0002] Currently, in the application of a time-of-flight mass analyzer in a mass spectrometer, for example, when enriching ions through the time-of-flight mass analyzer, during the ion extraction stage for inputting into the time-of-flight mass analyzer, the extraction speeds and extraction times of ions with different mass-to-charge ratios are different. For example, ions with a small mass-to-charge ratio have a fast extraction speed, and ions with a large mass-to-charge ratio have a slow extraction speed. As a result, when the window of the acceleration region of the mass spectrometer focusing device is fixed for the ions to enter, the effective mass-to-charge ratio range (the ratio range of the number of protons to the number of charges, i.e., the m / z range) in the ion time-of-flight mass spectrum (i.e., the TOF spectrum) is limited. Furthermore, when collecting ion mass spectrometry data in the time-of-flight mass analyzer subsequently, the ion utilization rate is low and the mass width of the time-of-flight mass spectrum is narrow. Summary of the Invention

[0003] In view of this, to solve the deficiencies of the prior art, the present application provides an ion extraction method, apparatus, and mass spectrometer.

[0004] In a first aspect, the present application provides an ion extraction method applied to a mass spectrometer. The mass spectrometer includes a vacuum chamber, and an introduction electrode, an ion transmission channel, a gate electrode, an ion storage unit, and an extraction electrode are sequentially arranged in the vacuum chamber. A collision cell is formed in the space between the introduction electrode, the ion transmission channel, and the gate electrode. The method includes:

[0005] Controlling target ions to be input from the introduction electrode into the collision cell of the vacuum chamber;

[0006] Applying a first voltage to the gate electrode to enable the target ions to enter the ion storage unit from the collision cell, and applying a second voltage to the extraction electrode to enable the target ions to accumulate in the ion storage unit;

[0007] After a preset time period, adjusting the magnitude of the first voltage and / or the second voltage so that the target ions are sequentially output from the extraction electrode in the order of decreasing mass-to-charge ratio.

[0008] In an optional embodiment, when adjusting the magnitude of the first voltage, controlling the voltage value of the second voltage to remain unchanged and increasing the voltage value of the first voltage so that the voltage value of the first voltage is greater than the voltage value of the second voltage;

[0009] When adjusting the magnitude of the second voltage, control the voltage value of the first voltage to remain unchanged, and decrease the voltage value of the second voltage so that the voltage value of the first voltage is greater than the voltage value of the second voltage.

[0010] In an alternative embodiment, adjusting the magnitude of the first voltage and / or the second voltage includes:

[0011] Controlling the output magnitude of the first voltage to increase in an arithmetic progression according to a predetermined voltage increase amount so that the voltage value of the first voltage is greater than the voltage value of the second voltage; and / or,

[0012] Controlling the output magnitude of the second voltage to decrease in an arithmetic progression according to a predetermined voltage decrease amount so that the voltage value of the first voltage is greater than the voltage value of the second voltage.

[0013] In an alternative embodiment, the vacuum chamber is provided with at least one opening, and each opening is used to introduce gas. The method further includes:

[0014] Applying a first radio frequency voltage to the ion transport channel so that the target ions collide with the gas to generate target ion fragments, and then the target ion fragments are output from the extraction electrode in order of decreasing mass-to-charge ratio under the action of the voltage applied to the gate electrode or the extraction electrode.

[0015] In an alternative embodiment, the mass spectrometer further includes a focusing device and a time-of-flight mass analysis device; the method further includes:

[0016] When controlling the target ions to be extracted from the extraction electrode and input to the focusing device, record the extraction time corresponding to the target ions, and adjust the magnitude of the pulsed repulsion voltage applied to the focusing device according to the extraction time so that target ions with different mass-to-charge ratios are input to the time-of-flight mass analysis device at the same moment to collect mass spectrometry data of the target ions with different mass-to-charge ratios.

[0017] In an alternative embodiment, the mass spectrometer further includes an ion mass analysis device; the method further includes:

[0018] Applying a second radio frequency voltage to the ion mass analysis device so that the target ions among the ions entering the mass spectrometer are input to the vacuum chamber under the action of the second radio frequency voltage.

[0019] In a second aspect, the present application provides an ion extraction device, which includes a vacuum chamber, and an introduction electrode, an ion transmission channel, a gate electrode, an ion storage unit, and an extraction electrode are sequentially arranged in the vacuum chamber; a space between the introduction electrode, the ion transmission channel, and the gate electrode forms a collision cell;

[0020] The ion extraction device is used to perform the steps of the ion extraction method as described in any one of the foregoing embodiments through the vacuum chamber.

[0021] In an optional embodiment, the introduction electrode, the ion transmission channel, the gate electrode, the ion storage unit, and the extraction electrode are coaxially arranged.

[0022] In an optional embodiment, the ion transmission channel is a combination structure of any one or more of a quadrupole, a hexapole, an octopole, a segmented quadrupole, a segmented hexapole, and a segmented octopole;

[0023] The extraction electrode includes a planar substrate and a plurality of conductive circular ring electrodes arranged on the planar substrate, and an ion extraction port is provided at the central position between the plurality of conductive circular ring electrodes.

[0024] In a third aspect, the present application provides a mass spectrometer, which includes the ion extraction device, a focusing device, and a time-of-flight mass analysis device as described in any one of the foregoing embodiments; the ion extraction device, the focusing device, and the time-of-flight mass analysis device are sequentially connected;

[0025] The mass spectrometer is used to extract target ions from the ion extraction device, and under the action of a pulsed repulsion voltage applied to the focusing device, so that target ions with different mass-to-charge ratios are input into the time-of-flight mass analysis device at the same moment, and then mass spectrometry data of target ions with different mass-to-charge ratios are collected.

[0026] The embodiments of the present application have the following beneficial effects:

[0027] In the embodiments of the present application, target ions are controlled to be input from the introduction electrode into the collision cell of the vacuum chamber; a first voltage is applied to the gate electrode to enable the target ions to enter the ion storage unit from the collision cell, and a second voltage is applied to the extraction electrode to enable the target ions to accumulate in the ion storage unit; after a preset time period, the magnitudes of the first voltage and / or the second voltage are adjusted so that the target ions are sequentially output from the extraction electrode in the order of decreasing mass-to-charge ratio. In the embodiments of the present application, by adjusting the magnitudes of the applied first voltage and / or second voltage, the target

[0028] The time for ions to be extracted from the extraction electrode is such that target ions with different mass-to-charge ratios are approximately introduced into the time-of-flight mass analyzer at the same time 5, so as to facilitate the subsequent time-of-flight mass analysis device to collect the time-of-flight mass spectrometry of target ions with different mass-to-charge ratios at the same

[0029] moment, and broaden the effective mass-to-charge ratio range of the time-of-flight mass spectrometry. Brief Description of the Drawings

[0030] To more clearly illustrate the technical solutions of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application,

[0031] and therefore should not be regarded as limiting the protection scope of the present application. In each drawing, similar components are numbered similarly.

[0032] Figure 1 Shows the first structural schematic diagram of the mass spectrometer in the embodiment of the present application;

[0033] Figure 2 Shows the second structural schematic diagram of the mass spectrometer in the embodiment of the present application;

[0034] 5 Figure 3 Shows the third structural schematic diagram of the mass spectrometer in the embodiment of the present application;

[0035] Figure 4 Shows a structural schematic diagram of the ion extraction device in the embodiment of the present application;

[0036] Figure 5 Shows a structural schematic diagram of the extraction electrode in the embodiment of the present application;

[0037] Figure 6 Shows the schematic diagram of the planar electric field on the extraction electrode in the embodiment of the present application;

[0038] Figure 7 Shows a schematic diagram of an implementation manner of the ion extraction method in the embodiment of the present application; 0 Figure 8 Shows the first change schematic diagram of the voltage amplitudes in the ion extraction device in the embodiment of the present application;

[0039] Figure 9 Shows the second change schematic diagram of the voltage amplitudes in the ion extraction device in the embodiment of the present application;

[0040] Figure 10 Shows the third change schematic diagram of the voltage amplitudes in the ion extraction device in the embodiment of the present application.

[0041] Description of main component symbols: 100 - ion extraction device; 110 - introduction electrode; 120 - ion transport channel; 130 - gate electrode; 140 - ion storage unit; 150 - extraction electrode; 151 - first conductive circular ring electrode; 152 - second conductive circular ring electrode; 153 - ion extraction port; 160 - opening; 200 - focusing device; 300 - time-of-flight mass analyzer; 400 - atmospheric pressure interface device; 500 - ion transport device; 600 - quadrupole transport device; 700 - quadrupole mass analyzer. Detailed implementation

[0042] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments.

[0043] Generally, the components of the embodiments of the present application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but merely represents the selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.

[0044] Hereinafter, the terms "including", "having" and their cognates that can be used in various embodiments of the present application are only intended to represent specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be construed as first excluding the existence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items or increasing the possibility of one or more features, numbers, steps, operations, elements, components or combinations of the foregoing items.

[0045] In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0046] Unless otherwise defined, all terms (including technical terms and scientific terms) used here have the same meaning as commonly understood by those of ordinary skill in the art to which the various embodiments of the present application belong. The terms (such as those defined in a commonly used dictionary) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and will not be interpreted as having an idealized meaning or being overly formal, unless clearly defined in the various embodiments of the present application.

[0047] The mass analyzers of mass spectrometers can be divided into various structures such as ion traps, quadrupoles, and time-of-flight. Different structures have different advantages. Ion traps can perform storage and mass analysis, and their advantage lies in the ability to perform tandem analysis; quadrupoles perform quantitative analysis through mass filtering; the time-of-flight mass analyzer has the technical advantages of high resolution and high mass accuracy, but at the same time has problems of low ion utilization rate and limited sensitivity.

[0048] Currently, most commercial instruments use the method of cascading multiple mass analyzers to achieve the superposition of advantageous functions. For example, triple quadrupoles add a collision cell on the basis of quantitative advantages to achieve accurate qualitative and quantitative analysis, and it is also one of the most widely used mass spectrometers in the market. In addition, a relatively common mass spectrometer is the quadrupole-time-of-flight mass spectrometer. By combining a quadrupole with a time-of-flight mass analyzer and a collision cell, cascade fragment information and mass spectrometry data with high mass accuracy and high resolution can be obtained. However, the quadrupole-time-of-flight mass spectrometer also has problems of low ion utilization rate and low duty cycle of the time-of-flight mass analyzer. Some instruments improve this by introducing the storage function of the ion trap and adding a storage structure to the transmission port.

[0049] Based on this, the embodiments of the present application provide an ion extraction method for correspondingly adjusting the output time of target ions by adjusting the voltage applied to the electrodes of the ion extraction device provided in the mass spectrometer, so that subsequent ions with different mass-to-charge ratios are in the modulation region (i.e., the acceleration region) of the time-of-flight mass analyzer within a certain time period, facilitating the time-of-flight mass analyzer to collect the time-of-flight mass spectrometry diagrams of ions with different mass-to-charge ratios at the same moment, broadening the effective mass-to-charge ratio range of the time-of-flight mass spectrometry diagram, and thus solving the technical problems of low ion utilization rate and low duty cycle in the time-of-flight mass analyzer.

[0050] Please refer to Figure 1 、 Figure 2 and Figure 3 In this application, a mass spectrometer is provided, including an ion extraction device 100, a focusing device 200, and a time-of-flight mass analysis device 300. Among them, the ion extraction device 100, the focusing device 200, and the time-of-flight mass analysis device 300 are connected in sequence. Among them, this mass spectrometer is a quadrupole-time-of-flight mass spectrometer.

[0051] In this embodiment, the mass spectrometer is used to extract target ions from the ion extraction device 100, and under the action of the pulsed repulsion voltage applied to the focusing device 200, each target ion with a different mass-to-charge ratio is input into the time-of-flight mass analysis device 300 approximately at the same moment. Then, the mass spectrometer collects the mass spectrometry data of each target ion with a different mass-to-charge ratio at the current moment through the time-of-flight mass analysis device 300.

[0052] As an optional implementation, the mass spectrometer further includes an atmospheric pressure interface device 400 , an ion transmission device 500 , a quadrupole transmission device 600 , and a quadrupole mass analyzer 700 .

[0053] Exemplarily, the atmospheric pressure interface device 400, the ion transmission device 500, the quadrupole transmission device, the quadrupole mass analyzer, the ion extraction device 100, the focusing device 200, and the time-of-flight mass analysis device 300 are placed sequentially and coaxially.

[0054] In this embodiment, the atmospheric pressure interface device 400 is used to introduce ions to achieve the transition from atmospheric pressure to vacuum environment. Then, the ions enter the ion transmission device 500 through the atmospheric pressure interface device 400, the ions are focused in the ion transmission device 500, and are introduced into the quadrupole transmission device 600, and the third radio frequency voltage and bias voltage are applied to the quadrupole transmission device to guide the ions to move forward through the applied voltage and enter the quadrupole mass analyzer 700.

[0055] A fourth radio frequency voltage with the same phase is applied to the opposite rods of the quadrupole mass analyzer, and a fifth radio frequency voltage with a phase difference of 180 degrees is applied to the adjacent rods of the quadrupole mass analyzer. The quadrupole mass analyzer 700 is used to couple the voltage for mass screening (Vsinwt+U, -(Vsinwt+U)), so as to screen out target ions from all ions through the voltage for mass screening, and introduce the target ions into the ion extraction device 100, that is, the target ions are pushed into the ion extraction device 100 through the voltage for mass screening, that is, the ions extracted from the quadrupole mass analyzer 700 are all target ions.

[0056] After being screened by the quadrupole mass analyzer, the target ions enter the ion extraction device 100, which is used to adjust the extraction time of target ions with different mass-to-charge ratios by the magnitude of the applied voltage, so that the target ions with different mass-to-charge ratios are introduced into the focusing device 200 in order from large to small mass-to-charge ratio, and the target ions are introduced into the time-of-flight mass analyzer 300 under the action of the voltage value applied to the focusing device 200.

[0057] Optionally, the atmospheric pressure interface device 400 may adopt a capillary, a cone or the like; the ion transmission device 500 may adopt an ion funnel; the quadrupole mass analyzer 700 and the quadrupole transmission device 600 may both adopt quadrupoles for corresponding settings. The structural composition and specific settings of each device or component in the mass spectrometer are not limited here, and may be set accordingly according to actual conditions.

[0058] Based on this, please refer to Figure 4, an embodiment of the present application further provides an ion extraction device 100, which includes a vacuum chamber, and an introduction electrode 110, an ion transmission channel 120, a gate electrode 130, an ion storage unit 140, and an extraction electrode 150 are sequentially arranged in the vacuum chamber; wherein, the space between the introduction electrode 110, the ion transmission channel 120, and the gate electrode 130 forms a collision cell.

[0059] In this embodiment, voltages are applied to each electrode or unit in the ion extraction device 100 to enable the ion extraction device 100 to control the extraction time of target ions.

[0060] Specifically, a third DC voltage (i.e., DC0) is applied to the introduction electrode 110, a first RF voltage (i.e., RF0) and a fourth DC voltage are applied to the ion transmission channel 120, a sixth RF voltage (i.e., RF2) and a seventh RF voltage (i.e., AC) are applied to the ion storage unit 140, a first voltage (i.e., DC voltage DC1) is applied to the gate electrode 130, and a second voltage is applied to the extraction electrode 150, where the second voltage is an RF voltage (i.e., RF3) and / or a DC voltage (i.e., DC3).

[0061] That is, the second voltage applied to the extraction electrode 150 can be a DC voltage, or an RF voltage, or a combination of a DC voltage and an RF voltage.

[0062] Optionally, the first RF voltage applied to the ion transmission channel 120 and the sixth RF voltage of the ion storage unit 140 can be RF voltages of the same amplitude or different amplitudes. The first voltage can change in an equal gradient, linearly, or non-linearly.

[0063] Exemplarily, the introduction electrode 110, the ion transmission channel 120, the gate electrode 130, the ion storage unit 140, and the extraction electrode 150 are coaxially arranged.

[0064] Optionally, the ion transmission channel 120 is any one or a combination of a quadrupole, a hexapole, an octopole, a segmented quadrupole, a segmented hexapole, and a segmented octopole; in addition, the ion transmission channel 120 can also adopt a lens group structure composed of multiple sets of pole pieces; the structure of the ion transmission channel 120 is not limited in this embodiment. Optionally, the ion storage unit 140 is a transmission quadrupole.

[0065] Optionally, the extraction electrode 150 includes multiple sets of electrodes; preferably, as Figure 5 shown, the extraction electrode 150 includes a planar substrate and a plurality of conductive circular ring electrodes arranged on the planar substrate (such as Figure 5The first conductive circular ring electrode 151 and the second conductive circular ring electrode 152 shown are not connected to each other, and an ion extraction port 153 is provided at the central position between the plurality of conductive circular ring electrodes. The diameter range of the ion extraction port 153 is 0.5 mm - 10 mm. In addition, the conductive circular ring electrodes can be formed by performing corresponding wiring settings on a printed circuit board. Optionally, the width range of the coaxial conductive circular ring electrodes is 0.01 - 10 mm, and there is a certain gap between adjacent conductive circular ring electrodes. As Figure 6 shown, when a voltage is applied to the extraction electrode 150 correspondingly, a planar electric field can be formed.

[0066] Furthermore, there is a voltage difference (DC2) between the extraction electrode 150 at the central position (i.e., the ion extraction port 153) and the edge conductive circular ring electrode, and thus a gradient electric field can be formed; when a radio frequency voltage is applied to the extraction electrode 150, there is a 180° phase difference between adjacent conductive circular ring electrodes.

[0067] As an optional implementation manner, the ion extraction device 100 further includes a power supply unit (not shown in the figure) to supply power to each unit or electrode in the ion extraction device 100 through the power supply unit.

[0068] Optionally, the ion transport channel 120 and the ion storage unit 140 can be in the same vacuum environment or in different vacuum environments. In addition, the ion transport channel 120 and the ion storage unit 140 can be of a connection structure.

[0069] Based on this, as Figure 7 shown, an embodiment of the present application further provides an ion extraction method, which is applied to the mass spectrometer in the above embodiment, specifically applied to the ion extraction device 100 of the mass spectrometer. The method includes:

[0070] S10, controlling the target ions to be input from the introduction electrode 110 into the collision cell in the vacuum chamber.

[0071] The target ions are introduced from the introduction electrode 110 of the vacuum chamber of the ion extraction device 100 into the collision cell; wherein, the ion extraction device 100 is in a vacuum environment.

[0072] Specifically, after the target ions pass through the atmospheric pressure interface device 400, the ion transport device 500, the quadrupole transport device, and the quadrupole mass analyzer, they are introduced into the ion extraction device 100, and then the target ions are sequentially extracted by the ion extraction device 100 in the order of decreasing mass-to-charge ratio, and enter the time-of-flight mass analysis device 300 through the focusing device 200. The mass spectrometry data of each target ion with different mass-to-charge ratios is collected by the time-of-flight mass analyzer to generate a time-of-flight mass spectrum.

[0073] S20. Apply a first voltage to the gate electrode 130 to cause target ions to enter the ion storage unit 140 from the collision cell, and apply a second voltage to the extraction electrode 150 to cause the target ions to accumulate in the ion storage unit 140.

[0074] In this embodiment, the ion storage unit 140 in the ion extraction device 100 and the ion transport channel 120 are in the same vacuum environment and are isolated by the gate electrode 130. After the target ions enter the ion storage unit 140, through the combined action of the voltages applied to the gate electrode 130 and the extraction electrode 150, the accumulation and cooling of the target ions are achieved.

[0075] Specifically, the target ions enter the collision cell through the gate electrode 130, enter the ion storage unit 140 under the action of the first voltage (i.e., the DC voltage DC1) applied to the gate electrode 130, and are trapped in the ion storage unit 140 under the action of the second voltage (DC voltage DC3 and / or RF voltage RF3) applied to the extraction electrode 150. That is, the target ions enter the ion storage unit 140 for ion accumulation under the interaction of the first voltage and the second voltage.

[0076] S30. After a preset time period, adjust the magnitude of the first voltage and / or the second voltage so that the target ions are sequentially output from the extraction electrode 150 in the order of decreasing mass-to-charge ratio.

[0077] In this embodiment, after the ion accumulation for a preset time period, the gate electrode 130 is closed. Then, by adjusting the magnitude of the first voltage applied to the gate electrode 130 and / or the magnitude of the second voltage applied to the extraction electrode 150, the target ions can be sequentially extracted from the extraction electrode 150 in a predetermined order. The specific time range of this preset time period is not limited here and can be set according to the actual situation.

[0078] In one embodiment, when adjusting the magnitude of the first voltage, control the voltage value of the second voltage to remain unchanged and increase the voltage value of the first voltage so that the voltage value of the first voltage is greater than the voltage value of the second voltage. When adjusting the magnitude of the second voltage, control the voltage value of the first voltage to remain unchanged and decrease the voltage value of the second voltage so that the voltage value of the first voltage is greater than the voltage value of the second voltage.

[0079] Further, in one embodiment, control the output magnitude of the first voltage to increase in an arithmetic progression according to a predetermined voltage increment so that the voltage value of the first voltage is greater than the voltage value of the second voltage; or, control the output magnitude of the second voltage to decrease in an arithmetic progression according to a predetermined voltage decrement so that the voltage value of the first voltage is greater than the voltage value of the second voltage.

[0080] Furthermore, when adjusting the first voltage to sequentially extract target ions from the extraction electrode 150, the extraction time of each target ion is directly proportional to the voltage value of the first voltage. That is, when the voltage value of the first voltage is larger, the extraction time of the target ion is shorter, and the extraction speed of the target ion is faster.

[0081] When adjusting the second voltage to sequentially extract target ions from the extraction electrode 150, the extraction time of each target ion is inversely proportional to the voltage value of the second voltage. That is, when the voltage value of the second voltage is smaller, the extraction time of the target ion is shorter, and the extraction speed of the target ion is faster.

[0082] It should be noted that if the second voltage applied to the extraction electrode 150 is a DC voltage (i.e., DC3), when adjusting the second voltage to extract target ions, the voltage value of the applied DC voltage (i.e., DC3) is correspondingly adjusted; if the second voltage applied to the extraction electrode 150 is an RF voltage (i.e., RF3), during the target ion extraction stage, the voltage value of the RF voltage (i.e., RF3) is correspondingly adjusted; if the second voltage applied to the extraction electrode 150 is an RF voltage (i.e., RF3) and a DC voltage (i.e., DC3), during the target ion extraction stage, only the voltage value of one of them can be adjusted, that is, keeping the voltage value of the RF voltage unchanged and adjusting the voltage value of the DC voltage, or keeping the voltage value of the DC voltage unchanged and adjusting the voltage value of the RF voltage.

[0083] As an optional implementation manner, the vacuum chamber is provided with at least one opening 160, and each opening 160 is used to introduce gas. Among them, the introduced gas can be any gas, and its gas flow rate range is 0 - 100 mL / min; for example, nitrogen gas at 0.6 mL / min is introduced through the opening 160.

[0084] By applying a first RF voltage (i.e., RF0) to the ion transport channel 120, the target ions collide with the introduced gas to generate target ion fragments. Then, the target ion fragments are sequentially output from the extraction electrode 150 in the order of decreasing mass-to-charge ratio under the action of the voltage applied to the gate electrode 130 or the extraction electrode 150.

[0085] In one embodiment, the target ions enter the collision cell through the gate electrode 130, are confined under the action of the first radio frequency voltage applied to the ion transport channel 120, and collide with the introduced gas to generate target ion fragments; then, the target ion fragments enter the ion storage unit 140 under the action of the first voltage (i.e., the DC voltage DC1) applied to the gate electrode 130, and are trapped in the ion storage unit 140 under the action of the second voltage (DC voltage DC3 and / or radio frequency voltage RF3) applied to the extraction electrode 150; after a period of ion accumulation, the gate electrode 130 is closed; then, the voltage value of the first voltage is gradually increased so that the target ion fragments are extracted from the ion storage unit 140 in a certain order and enter the focusing device 200 connected to the ion extraction device 100 in the mass spectrometer.

[0086] In one embodiment, the target ions enter the collision cell through the introduction electrode 110, are confined under the action of the first radio frequency voltage applied to the ion transport channel 120, and collide with the introduced gas to generate target ion fragments; then, when the target ion fragments pass through the gate electrode 130, they enter the ion storage unit 140 under the action of the first voltage, and are trapped in the ion storage unit 140 under the action of the second voltage applied to the extraction electrode 150; after a period of ion accumulation, the gate electrode 130 is closed; then, the voltage value of the second voltage (DC voltage DC3 or radio frequency voltage RF3) is gradually decreased so that the target ion fragments are extracted from the ion storage unit 140 in a certain order and enter the focusing device 200 of the mass spectrometer.

[0087] It should be noted that the extraction electrode 150 is an ion blanket device, and applying a radio frequency voltage on the extraction electrode 150 will form a pseudopotential well. For ions or ion fragments with different mass-to-charge ratios, at the same radio frequency amplitude, the larger the mass-to-charge ratio, the smaller the charge amount, and the larger the mass-to-charge ratio, the smaller the depth of the pseudopotential well; furthermore, during the process of decreasing the radio frequency voltage amplitude, ions or ion fragments with a large mass-to-charge ratio are preferentially and unstably extracted.

[0088] It is worth noting that the target ions or target ion fragments can be extracted by adjusting the voltage values of the first voltage and / or the second voltage. Specifically, the following adjustment methods are included: 1. Increasing the voltage value of the first voltage (i.e., the DC voltage DC1); 2. Decreasing the applied radio frequency voltage (i.e., RF3) or DC voltage (i.e., DC3); 3. Decreasing the applied radio frequency voltage (i.e., RF3) and DC voltage (i.e., DC3); 4. Increasing the voltage value of the first voltage (i.e., the DC voltage DC1) and decreasing the radio frequency voltage (i.e., RF3) and / or DC voltage (i.e., DC3).

[0089] As an alternative embodiment, Figure 8When the target ion or target ion fragment is extracted from the extraction electrode 150 by adjusting the magnitude of the radio frequency voltage (i.e., RF3) applied to the extraction electrode 150, the magnitude changes of the first voltage (i.e., DC voltage DC1) applied to the gate electrode 130, and the radio frequency voltage (i.e., RF3) and DC voltage (DC3) applied to the extraction electrode 150.

[0090] It can be understood that a radio frequency voltage (i.e., RF3) and a DC voltage (DC3) are applied to the extraction electrode 150. During the extraction stage of the target ion or target ion fragment, the magnitude of the radio frequency voltage applied to the extraction electrode 150 is changed to gradually extract the target ion or target ion fragment; that is, by reducing the voltage value of the applied radio frequency voltage, the target ion or target ion fragment is extracted from the extraction electrode 150.

[0091] Optionally, as Figure 9 shown, Figure 9 When the target ion or target ion fragment is extracted from the extraction electrode 150 by adjusting the magnitude of the first voltage (i.e., DC voltage DC1) applied to the gate electrode 130, the magnitude changes of the first voltage (i.e., DC voltage DC1) applied to the gate electrode 130, and the radio frequency voltage (i.e., RF3) and DC voltage (DC3) applied to the extraction electrode 150.

[0092] Among them, as Figure 9 shown, during the stage when the target ion is introduced from the introduction electrode 110, the voltage value of the first voltage is small, and then the voltage value gradually increases, so as to extract the target ion or target ion fragment trapped in the ion storage unit 140. Among them, a radio frequency voltage (i.e., RF3) and a DC voltage (DC3) are applied to the extraction electrode 150. When the target ion or target ion fragment is extracted by adjusting the voltage value of the first voltage, the magnitude of the radio frequency voltage (i.e., RF3) can remain unchanged, or during the stage when the target ion or target ion is extracted from the extraction electrode 150, the magnitude of the radio frequency voltage (i.e., RF3) is gradually reduced. The magnitude of the DC voltage (i.e., DC3) remains unchanged.

[0093] Optionally, as Figure 10 shown, Figure 10 When the target ion or target ion fragment is extracted from the extraction electrode 150 by adjusting the magnitude of the DC voltage (i.e., DC3) applied to the extraction electrode 150, the magnitude changes of the first voltage (i.e., DC voltage DC1) applied to the gate electrode 130, the sixth radio frequency voltage (i.e., RF2) and the seventh radio frequency voltage (i.e., AC) applied to the ion storage unit 140, and the magnitude change of the DC voltage (i.e., DC3) applied to the ion extraction electrode 150.

[0094] It can be understood that when the voltage value of the DC voltage (i.e., DC3) is gradually decreased over time to extract the target ion or target ion fragment, the amplitudes of the sixth RF voltage (i.e., RF2) and the seventh RF voltage (i.e., AC) can both remain unchanged.

[0095] In summary, in this embodiment, regardless of whether the target ion in the ion extraction device 100 collides with the gas, the target ion can be extracted in the order of decreasing mass-to-charge ratio by changing the timing of the power supply voltage applied to the gate electrode 130 or the extraction electrode 150 in the ion extraction device 100; and during this process, the extraction speed and extraction time of the target ion can be correspondingly adjusted by adjusting the first voltage and / or the second voltage, thereby achieving the wide-range extraction of the target ion.

[0096] In one embodiment, a second RF voltage is applied to the ion mass analysis device so that the target ion among the ions entering the mass spectrometer is input into the vacuum chamber under the action of the second RF voltage. That is, in this ion mass analysis device, the target ion is introduced from the ion mass analysis device into the ion extraction device 100 under the action of the second RF voltage, realizing the screening of ions.

[0097] In one embodiment, when controlling the target ion to be extracted from the extraction electrode 150 and input into the focusing device 200, the extraction time corresponding to the target ion is recorded, and the magnitude of the pulsed repulsion voltage applied to the focusing device 200 is adjusted according to the extraction time, so that each target ion with a different mass-to-charge ratio is input into the time-of-flight mass analysis device 300 at the same moment to collect the mass spectrometry data of each target ion with a different mass-to-charge ratio.

[0098] Specifically, after the target ion accumulates in the ion storage unit 140 for a period of time, by changing the scanning timings of the eighth RF voltage and the second voltage applied to the extraction electrode 150 and in combination with the first voltage applied to the gate electrode 130, the target ion is extracted from the extraction electrode 150 in the order of decreasing mass-to-charge ratio. And the extraction time of the target ion with different mass-to-charge ratios can be correspondingly adjusted by adjusting the scanning timings of the eighth RF voltage and the second voltage applied to the extraction electrode 150.

[0099] After the target ion is extracted through the extraction electrode 150, it enters the time-of-flight mass analysis device 300 through the focusing device 200. When different mass-to-charge ratio target ions pass through the focusing device 200, they approximately reach the acceleration region in the focusing device 200 at the same time point, and under the action of the pulsed repulsion voltage applied to the focusing device 200, the target ion is introduced into the time-of-flight mass analysis device 300.

[0100] Further, target ions with different mass-to-charge ratios are approximately input into the time-of-flight mass analyzer 300 at the same moment. Then, the mass spectrometer acquires mass spectrometry data of the target ions with different mass-to-charge ratios at the current moment through the time-of-flight mass analyzer 300, that is, it can simultaneously acquire mass spectrometry data of the target ions with different mass-to-charge ratios.

[0101] It can be understood that by controlling the output time of target ions with different mass-to-charge ratios through the ion extraction device 100, the target ions can be approximately input into the time-of-flight mass analyzer 300 at the same moment, so as to correspondingly acquire mass spectrometry data of the target ions with different mass-to-charge ratios at the same moment, improve the acquisition efficiency of the mass spectrometry data, and facilitate the analysis of the target ions with different mass-to-charge ratios through the acquired mass spectrometry data, thereby improving the ion utilization rate in the time-of-flight mass analyzer 300 and increasing the mass width during the generation of the mass spectrometry data of the ions.

[0102] In this embodiment, by adjusting the magnitude of the first voltage applied to the gate electrode and / or the second voltage applied to the extraction electrode, the extraction time of target ions with different mass-to-charge ratios from the extraction electrode is correspondingly adjusted, so as to control the target ions with different mass-to-charge ratios to be approximately introduced into the time-of-flight mass analyzer at the same moment, facilitating the subsequent time-of-flight mass analyzer to acquire the time-of-flight mass spectrometry diagrams of the target ions with different mass-to-charge ratios at the same moment and broadening the effective mass-to-charge ratio range of the time-of-flight mass spectrometry diagram.

[0103] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and structure diagrams in the accompanying drawings show the possible architectures, functions, and operations of devices, methods, and computer program products according to multiple embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in an alternative implementation, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the structure diagram and / or flowchart, as well as the combination of blocks in the structure diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0104] In addition, each functional module or unit in various embodiments of the present application may be integrated together to form an independent part, or each module may exist alone, or two or more modules may be integrated to form an independent part.

[0105] If the above-mentioned function is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a smart phone, a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present application.

[0106] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application.

Claims

1. An ion extraction method, characterized in that, Applied to a mass spectrometer, the mass spectrometer includes a vacuum chamber, a focusing device, and a time-of-flight mass analysis device. An introduction electrode, an ion transmission channel, a gate electrode, an ion storage unit, and an extraction electrode are sequentially arranged in the vacuum chamber. A space between the introduction electrode, the ion transmission channel, and the gate electrode forms a collision cell, such that target ions collide with introduced gas in the collision cell to generate target ion fragments. The method includes: Controlling the input of target ions from the introduction electrode into the collision cell of the vacuum chamber; Applying a first voltage to the gate electrode to enable the target ions to enter the ion storage unit from the collision cell, and applying a second voltage to the extraction electrode to enable the target ion fragments output from the collision cell to accumulate target ions in the ion storage unit; After a preset time period, adjusting the magnitude of the first voltage and / or the second voltage such that the target ion fragments are sequentially output from the extraction electrode in descending order of mass-to-charge ratio. Wherein, adjusting the magnitude of the first voltage and / or the second voltage includes: controlling the output magnitude of the first voltage to increase in an arithmetic progression according to a predetermined voltage increment amount such that the voltage value of the first voltage is greater than the voltage value of the second voltage; and / or, controlling the output magnitude of the second voltage to decrease in an arithmetic progression according to a predetermined voltage decrement amount such that the voltage value of the first voltage is greater than the voltage value of the second voltage; When controlling the extraction of the target ion fragments from the extraction electrode and inputting them into the focusing device, recording the extraction time corresponding to the target ion fragments, and adjusting the magnitude of the pulsed repulsion voltage applied to the focusing device according to the extraction time, such that target ion fragments with different mass-to-charge ratios are input into the time-of-flight mass analysis device at the same moment to collect mass spectrometry data of the target ion fragments with different mass-to-charge ratios.

2. The ion extraction method according to claim 1, characterized in that When adjusting the magnitude of the first voltage, controlling the voltage value of the second voltage to remain unchanged and increasing the voltage value of the first voltage such that the voltage value of the first voltage is greater than the voltage value of the second voltage; When adjusting the magnitude of the second voltage, controlling the voltage value of the first voltage to remain unchanged and decreasing the voltage value of the second voltage such that the voltage value of the first voltage is greater than the voltage value of the second voltage.

3. The ion extraction method according to claim 1, characterized in that The vacuum chamber is provided with at least one opening for introducing gas. The method further includes: Applying a first radio frequency voltage to the ion transmission channel such that the target ions collide with the gas to generate the target ion fragments, and further enabling the target ion fragments to be sequentially output from the extraction electrode in descending order of mass-to-charge ratio under the action of the voltage applied to the gate electrode or the extraction electrode.

4. The ion extraction method according to claim 1, characterized in that, The mass spectrometer further includes an ion mass analysis device. The method further includes: Applying a second radio frequency voltage to the ion mass analysis device such that target ions among the ions entering the mass spectrometer are input into the vacuum chamber under the action of the second radio frequency voltage.

5. An ion extraction device, characterized in that, The ion extraction device includes a vacuum chamber, in which an introduction electrode, an ion transmission channel, a gate electrode, an ion storage unit and an extraction electrode are sequentially arranged; a space between the introduction electrode, the ion transmission channel and the gate electrode forms a collision cell, so that target ions collide with introduced gas in the collision cell to generate target ion fragments. The ion extraction device is used to perform the steps of the ion extraction method according to any one of claims 1-4 through the vacuum chamber.

6. The ion extraction device according to claim 5, wherein, The introduction electrode, the ion transmission channel, the gate electrode, the ion storage unit and the extraction electrode are coaxially arranged.

7. The ion extraction device according to claim 5, characterized in that, The ion transmission channel is a combined structure of any one or more of a quadrupole, a hexapole and an octopole. The extraction electrode includes a planar substrate and a plurality of conductive circular ring electrodes arranged on the planar substrate, and an ion extraction port is arranged at the central position between the plurality of conductive circular ring electrodes.

8. A mass spectrometer, characterized in that, It includes the ion extraction device, a focusing device and a time-of-flight mass analysis device according to any one of claims 5-7; the ion extraction device, the focusing device and the time-of-flight mass analysis device are sequentially connected. The mass spectrometer is used to extract target ion fragments from the ion extraction device, and under the action of a pulsed repulsion voltage applied to the focusing device, so that each target ion fragment with different mass-to-charge ratios is input into the time-of-flight mass analysis device at the same moment, and then mass spectrometry data of each target ion fragment with different mass-to-charge ratios is collected.

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